Patent Publication Number: US-11646812-B2

Title: Optical communications module related systems and methods

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     The present application is a continuation of and claims priority from U.S. patent application Ser. No. 16/725,821, filed Dec. 23, 2019, which claims priority from U.S. patent application Ser. No. 16/234,432, filed Dec. 27, 2018, which claims priority from U.S. patent application Ser. No. 15/877,247, filed Jan. 22, 2018, which claims priority from U.S. Provisional Patent Application No. 62/536,431, filed Jul. 24, 2017, and from U.S. Provisional Patent Application No. 62/448,663, filed Jan. 20, 2017, the disclosures of which are incorporated by reference as set forth in full. 
    
    
     FIELD OF INVENTION 
     This disclosure relates generally to the field of optical telecommunications and includes an integrated module with several sub-assemblies. 
     BACKGROUND 
     To understand the importance of optical networking, the capabilities of this technology have to be discussed in the context of the challenges faced by the telecommunications industry, and, in particular, service providers. Most U.S. networks were built using estimates that calculated bandwidth use by employing concentration ratios derived from classical engineering formulas for modeling network usage such as the Poisson process. Consequently, forecasts of the amount of bandwidth capacity needed for data networks were calculated on the presumption that a given individual would only use network bandwidth six minutes of each hour. These formulas did not factor in the amount of traffic generated by different devices accessing the Internet. With the advent of the Internet and the ever increasing number of devices (e.g., facsimile machines, multiple phone lines, modems, teleconferencing equipment, mobile devices including smart phones, tablets, laptops, wearable devices, and Internet of Things (IoT) devices, etc.) accessing the Internet, there has been an average increase in Internet traffic of 300 percent year over year. Had these factors been included, a far different estimate would have emerged. 
     As a result of this explosive growth of devices, an enormous amount of bandwidth capacity is required to provide the services required by these devices. In the 1990s, some long-distance carriers increased their capacity (bandwidth) to 1.2 Gbps over a single optical fiber pair, which was a considerable upgrade at the time. At a transmission speed of one Gbps, one thousand books can be transmitted per second. However today, if one million families in a city decided to view a video on a Web site (e.g., YouTube, Home Box Office (HBO) on the go, DirectTV, etc.) then network transmission rates on the order of terabits are required. With a transmission rate of one terabit, it is possible to transmit 200 million simultaneous full duplex phone calls or transmit the text from 300 years-worth of daily newspapers per second. 
     When largescale data networks providing residential, commercial, and enterprise customers with Internet access were first deployed, the unprecedented growth in the number of devices accessing the network could not have been imagined. As a result, the network growth requirements needed in order to meet the demand of the devices were not considered at that time either. For example, from 1994 to 1998, it is estimated that the demand on the U.S. interexchange carriers&#39; (IXC&#39;s) network would increase sevenfold, and for the U.S. local exchange carriers&#39; (LEC&#39;s) network, the demand would increase fourfold. For instance, some cable companies indicated that their network growth was 32 times the previous year, while other cable companies have indicated that the size of their networks have doubled every six months in a four-year period. 
     In addition to this explosion in consumer demand for bandwidth, many service provider are coping with optical fiber exhaust in their network. For example, in 1995 alone many Internet Service Provider (ISP) companies indicated that the amount of embedded optical fibers already in use at the time was between 70 percent and 80 percent (i.e., 70 to 80 percent of the capacity of their networks were used the majority of the time to provide service to customers). Today, many cable companies are nearing one hundred percent capacity utilization across significant portions of their networks. Another problem for cable companies is the challenge of deploying and integrating diverse technologies in on physical infrastructure. Customer demands and competitive pressures mandate that carriers offer diverse services economically and deploy them over the embedded network. One potential technology that meets these requirements is based on multiplexing a large and diverse number of data, regardless of the type of data, onto a beam of light that may be attenuated to propagate at different wavelengths. The different types of data may comprise facsimile sources, landline voice sources, voice over Internet Protocol (VOIP) sources, video sources, web browser sources, mobile device sources including voice application sources, short messaging service (SMS) application sources, multimedia messaging service (MMS) application sources, mobile phone third party application (app) sources, and/or wearable device sources. When a large and diverse number of data sources, such as the ones mentioned in the previous sentence, are multiplexed together over light beams transmitted on an optical fiber, it may be referred to as a dense wave division multiplexing (DWDM). 
     The use of an optical communications module link extender (OCML) circuit as described herein allows cable companies to offer these services regardless of the open systems interconnection (OSI) model network layer (layer 3) protocols or media access control (MAC) (layer 2) protocols that are used by the different sources to transmit data. For example, e-mail, video, and/or multimedia data such as web based content data, may generate IP (layer 3) data packets that are transmitted in asynchronous transfer mode (ATM) (layer 2) frames. Voice (telephony) data may be transmitted over synchronous optical networking (SONET)/synchronous digital hierarchy (SDH). Therefore regardless of which layer is generating data (e.g., IP, ATM, and/or SONET/SDH) a DWDM passive circuit provides unique bandwidth management by treating all data the same. This unifying capability allows cable companies with the flexibility to meet customer demands over a self-contained network. 
     A platform that is able to unify and interface with these technologies and position the cable company with the ability to integrate current and next-generation technologies is critical for a cable company&#39;s success. 
     Cable companies faced with the multifaceted challenge of increased service needs, optical fiber exhaust, and layered bandwidth management, need options to provide economical and scalable technologies. One way to alleviate optical fiber exhaust is to lay more optical fiber, and, for those networks where the costs of laying new optical fiber is minimal, the best solution may be to lay more optical fiber. This solution may work in more rural areas, where there may be no considerable population growth. However, in urban or suburban areas laying new optical fiber may be costly. Even if it was not costly, the mere fact that more cable is being laid does not necessarily enable a cable company to provide new services or utilize the bandwidth management capabilities of the unifying optical transmission mechanism such as DWDM. 
     Another solution may be to increase the bit rate using time division multiplexing (TDM). TDM increases the capacity of an optical fiber by slicing time into smaller time intervals so that more bits of data can be transmitted per second. Traditionally, this solution has been the method of choice, and cable companies have continuously upgraded their networks using different types of digital signaling technologies to multiplex data over SONET/SDH networks. For example, Digital Signal (DS) DS-1, DS-2, DS-3, DS-4, and DS-5, commonly referred to as T1, T2, T3, T4, or T5 lines, are different carrier signals, that are transmitted over SONET/SDH networks that can carry any of the sources of data mentioned above, whose data rates increase with the number assigned to the DS. That is DS-1 was the earliest carrier signal used to transmit data over SONET/SDH networks, and has the lowest data rate and DS-5 is the most recent carrier signal use to transmit data over SONET/SDH networks with the highest data rate. Cable company networks, especially SONET/SDH networks have evolved over time to increase the number of bits of data that can be transmitted per second by using carrier signals with higher data rates. However, when cable companies use this approach, they must purchase capacity based on what the SONET/SDH standard dictates will be the next increase in capacity. For example, cable companies can purchase a capacity of 10 Gbps for TDM, but should the capacity not be enough the cable companies will have to purchase a capacity of 40 Gbps for TDM, because there are no intermediate amounts of capacity for purchase. In such a situation, a cable company may purchase a significant amount of capacity that they may not use, and that could potentially cost them more than they are willing to pay to meet the needs of their customers. Furthermore, with TDM based SONET/SDH networks, the time intervals can only be reduced to a certain size beyond which it is no longer possible to increase the capacity of a SONET/SDH network. For instance, increasing the capacity of SONET/SDH networks to 40 Gbps using TDM technology may prove to be extremely difficult to achieve in the future. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    depicts a schematic of an Optical Communications Module Link (OCML) Extender, in accordance with the disclosure. 
         FIG.  2    depicts a network architecture, in accordance with the disclosure. 
         FIG.  3    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  4    shows an access link loss budget of a Dense Wave Division Multiplexing (DWDM) passive circuit, in accordance with the disclosure. 
         FIG.  5    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  6    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  7    depicts different passive optical network (PON) transceiver parameters associated with downstream transmitting circuits and upstream transmitting circuits, in accordance with the disclosure. 
         FIG.  8    depicts a graphical representation of wavelengths used to transport one or more signals, in accordance with the disclosure. 
         FIG.  9    depicts a stimulated Raman scattering (SRS) diagram, in accordance with the disclosure. 
         FIG.  10    depicts a schematic illustration of wavelength and optical fiber monitoring of cascaded OCML headends in accordance with the disclosure. 
         FIG.  11    depicts a schematic illustration of wavelength and optical fiber monitoring of an OCML headend in accordance with the disclosure. 
         FIG.  12    depicts an access network diagram of an OCML headend comprising wavelength division multiplexers (WDMs), a dense wavelength division multiplexer (DWDM), and optical amplifiers, in accordance with the disclosure. 
         FIG.  13    depicts an access network diagram of an OCML headend comprising WDMs, a DWDM, optical amplifiers, and dispersion control modules (DCMs), in accordance with the disclosure. 
         FIG.  14    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  15    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  16    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  17 A  depicts an access network diagram of an OCML headend, in accordance with the disclosure. 
         FIG.  17 B  depicts an access network diagram of a multiplexer-demultiplexer (MDM), in accordance with the disclosure. 
         FIG.  18    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. 
         FIG.  19    depicts a process of transmitting optical signals with the OCML headend, in accordance with the disclosure. 
         FIG.  20    depicts a process of transmitting optical signals with the OCML headend, in accordance with the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     DWDM passive circuits can be used in combination with one or more other optical communications devices to develop novel signal extension circuits that increase the range with which light beams are propagated and the number of signals that can be combined and transmitted from a cable company to customers. The circuits disclosed herein may be referred to as Optical Communications Module Link (OCML) Extender. The OCML passive circuits, disclosed herein, increase the capacity of embedded optical fibers by first assigning incoming optical signals to specific frequencies (wavelength, denoted by lambda) within a designated frequency band and then multiplexing the resulting signals out onto one optical fiber. Because incoming signals are never terminated in the optical layer, the interface can be bit-rate and format independent, thereby allowing the service provider to integrate DWDM passive circuits easily into a passive circuit, such as an OCML passive circuit, with existing equipment in the network while gaining access to the untapped capacity in the embedded optical fibers. 
     A DWDM passive circuit combines multiple optical signals for transportation over a single optical fiber, thereby increasing the capacity of a service provider&#39;s network. Each signal carried can be at a different rate (e.g., optical carrier transmission rate OC-3, OC-12, OC-24 etc.) and in a different format (e.g., SONET, ATM, data, etc.). For example, the networks disclosed herein comprise DWDM passive circuits that transmit and receive a mix of SONET signals with different data rates (e.g., OC-48 signals with a data rate of 2.5 Gbps or OC-192 signals with a data rate of 10 Gbps) can achieve data rates (capacities) of over 40 Gbps. The OCML passive circuits disclosed herein can achieve the aforementioned while maintaining the same degree of system performance, reliability, and robustness as current transport systems—or even surpassing it. The OCML passive circuits may be a smart platform, integrated into a network headend or a network cabinet, and may connect a metro area network that provides internet and telecommunications services to end users (e.g., enterprise multi dwelling unit (MDU) customers, residential customers, commercial customers, and industrial customers) via one or more optical fiber links. The OCML passive circuits may also be referred to as OCML headends. The OCML headend enables a plurality of signals to be cost effectively transported over long optical fiber distances between 5 km and 60 km without having to put any optical amplifiers or other active devices, like an optical switch, (which is normally used to provide path redundancy in case of an optical fiber cut) in the field. 
     The OCML headend is intended to transport a mix of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON signals over the same optical fiber without having active devices such as optical amplifiers in the field. The OCML headend is also configured to support the same wavelengths over a secondary optical fiber via an optical switch in case the primary optical fiber experiences a cut. In one embodiment, an OCML headend, systems, and methods include various subsystems integrated into a single module including an integrated DWDM passive circuit that combines and separates bi-directional wavelengths in optical fibers propagating in a conventional wavelength window, such as the c band dispersive region of the optical fibers. The OCML headend may comprise a three port or four port wave division multiplexer (WDM) or circulator to combine and separate 10 GbE downstream and upstream signals of different wavelengths. The OCML headend may also comprise a four port WDM to combine GPON, EPON, and 10 GbE optical signals of different wavelengths, whereas the DWDM combines SONSET/SDH and/or ATM signals. The OCML headend may also comprise a five port WDM to combine and separate upstream and downstream signals comprising GPON, XGPON/10GEPON, and 10 GbE optical data signals of different wavelengths. Although the term multiplexer is used to describe the WDMs as disclosed herein, the WDMs do not exclusively multiplex (combine) one or more downstream signals into a single downstream signal, but they also demultiplex (separate) a single upstream signal into one or more upstream signals. 
     The WDM may comprise one or more thin film filters (TFFs) or array waveguide gratings (AWGs) that combine one or more downstream signals into a single downstream signal and separate a single upstream signal into one or more upstream signals. The WDM may comprise one or more wavelength-converting transponders, wherein each of the wavelength-converting transponders receives an optical data signal (e.g., a 10 GbE optical data signal) from a client-layer optical network such as, for example, a Synchronous optical network (SONET)/synchronous digital hierarchy (SDH), Internet protocol (IP), and/or asynchronous transfer mode (ATM) optical network. Each of the wavelength-converting transponders converts the optical data signal into an electrical data signal, and then converts the electrical data signal into a second optical data signal to be emitted by a laser, wherein the second optical data signal is carried by one or more packets of light oscillating with wavelengths in the c band. More specifically, each of the wavelength-converting transponders may include a laser that emits the second optical data signal. That is each of the second optical data signals may be emitted by a laser with a unique wavelength. In some embodiments, the wavelength-converting transponders may comprise two adjacent transceivers. That is, each of the wavelength-converting transponders may comprise a first transceiver that converts the optical data signal into an electrical data signal, and may comprise a second transceiver that converts the electrical data signal into the second optical data signal. The second transceiver converts the electrical signal to the second optical data signal such that the second optical data signal is transmitted with the correct wavelength. 
     A first wavelength-converting transponder, of the two wavelength-converting transponders, may emit a second optical data signal with a 1550 nm wavelength. A second wavelength-converting transponder, of the two wavelength-converting transponders, may emit a second optical data signal with a 1533 nm wavelength. For example, there may be two wavelength-converting transponders, and each of the two wavelength-converting transponders may include a laser emitting a second optical data signal with a unique wavelength. Thus, each of the wavelength-converting transponders converts the electrical data signal into an optical data signal, and each of the wavelength-converting transponders emits, or transmits, the optical data signal, with a wavelength in the c band, to a TFF or AWG. The TFF or AWG, may combine or multiplex the optical data signals, emitted by each of the wavelength-converting transponders, into a multi-wavelength optical data signal wherein each of the wavelengths in the multi-wavelength optical data signal coincide with the wavelengths associated with each of the optical data signals. Returning to the example above of the two wavelength-converting transponders, the first and second wavelength-converting transponders, may each receive an optical signal from a SONET/SDH client layer network. The first and second wavelength-converting transponders may each respectively convert the optical signal they received from the SONET/SDH client layer network into an electrical data signal. The first wavelength-converting transponder may convert the electrical data signal that it receives into a second optical data signal with a first wavelength. The first wavelength-converting transponder may emit, via a first laser, the second optical data signal, with the first wavelength, to the TFF or AWG. The second wavelength-converting transponder may convert the electrical data signal that it receives into a second optical data signal with a second wavelength. The second wavelength-converting transponder may emit, via a second laser, the second optical signal, with the second wavelength, to the TFF or AWG. The TFF or AWG may combine or multiplex the second optical data signal, with the first wavelength, and the second optical data signal, with the second wavelength, onto a multi-wavelength optical signal. The TFF or AWG may be referred to as an optical multiplexer. 
     The DWDM passive circuits disclosed herein may include wavelength-converting transponders and corresponding WDMs that combine or multiplex optical data signals similar to the WDMs described above. The DWDM passive circuits may also include wavelength-converting transponders and corresponding WDMs that separate optical data signals. In some embodiments, the same WDM may combine optical data signals and separate optical data signals. That is, the WDM may separate one or more optical data signals from a multi-wavelength optical data signal, or demultiplex the one or more optical data signals from the multi-wavelength optical data signal. The WDM may separate the one or more optical data signals from a multi-wavelength optical data signal using a process that is the exact opposite of the process used to combine one or more optical data signals into a multi-wavelength signal. The WDM may separate one or more optical data signals from a multi-wavelength optical data signal that may correspond to an upstream signal received from a remote DWDM passive circuit. 
     The WDM may receive the multi-wavelength optical data signal and one or more TTF or AWGs may separate the one or more optical data signals, from the multi-wavelength optical data signal, using filters or waveguide gratings with properties that separate optical data signals, with different wavelengths, from a multi-wavelength optical data signal. After the WDM has separated the optical data signals, with different wavelengths, from the multi-wavelength optical data signal, the WDM may convert each of the separated optical data signals to a corresponding electrical data signal. The WDM may then convert the corresponding electrical data signal to a second optical data signal, wherein the second optical data signal may be an optical data signal with signal characteristics commensurate for use with a SONET/SDH, IP, or ATM client-layer optical network. 
     As mentioned above, the WDM may also be a circulator, or function as a circulator. The circulator in the WDM may be an optical circulator comprised of a fiber-optic component that can be used to separate upstream signals and downstream signals. The optical circulator may be a three-port or four-port device in which an optical data signal entering one port will exit the next port. The optical circulator may be in the shape of a square, with a first port on the left side of the square, a second port on the right side of the square, and a third port on the bottom side of the square. A first optical data signal (e.g., a downstream signal) entering the first port may exit the second port. A second optical data signal (e.g., an upstream signal) entering the third port may exit the first port. 
     An upstream signal, as referred to herein, may be a flow of one or more packets of light, oscillating with a predetermined wavelength, along one or more optical fibers in a direction toward the OCML headend from a field hub or outside plant. A downstream signal, as referred to herein, may be a flow of one or more packets of light, oscillating with a predetermined wavelength, along one or more optical fibers in a direction away from the OCML headend and toward the field hub or outside plant. The one or more packets of light may correspond to one or more bits of data. Both downstream and upstream signals propagate along the same optical fiber, but in opposite directions. In some embodiments, the downstream and upstream signals may propagate along the same fiber simultaneously using one or more wavelength multiplexing techniques as explained below. This bidirectional simultaneous communication between the OCML headend and the outside plant may be referred to as a full duplex connection. Field hub and outside plant may be used interchangeably. 
     In some embodiments, the OCML headend may also comprise a booster optical amplifier, that amplifies downstream signals based on the length of a fiber between the OCML headend and the outside plant. The booster optical amplifier may be an Erbium Doped Fiber Amplifier (EDFA). The core of the EDFA may be an erbium-doped optical fiber, which may be a single-mode fiber. The fiber may be pumped, by a laser, with one or more packets of light in a forward or backward direction (co-directional and counter-directional pumping). The one or more packets of light pumped into the fiber, may have a wavelength of 980 nm. In some embodiments the wavelength may be 1480 nm. As the one or more packets of light are pumped into the fiber erbium ions (Er 3+ ) are excited and transition into a state where the ions can amplify the one or more packets of light with a wavelength within the 1.55 micrometers range. The EDFA may also comprise two or more optical isolators. The isolators may prevent light pumped into the fiber that leaves the EDFA from returning to the EDFA or from damaging any other electrical components connected to the EDFA. In some embodiments, the EDFA may comprise fiber couplers and photodetectors to monitor optical power levels. In other embodiments, the EDFA may further comprise pump laser diodes with control electronics and gain flattening filters. The EDFA may have the effect of amplifying each of the one or more optical data signals, while they are combined in a multi-wavelength optical data signal, without introducing any effects of gain narrowing. In particular, the EDFA may simultaneously amplify the one or more optical data signals, each of which have a different wavelength, within a gain region of the EDFA. A gain of the booster optical amplifier may be based at least in part on the length of the fiber. In some embodiments, the length of the fiber may be between 5 and 60 kilometers. 
     The OCML headend may also comprise an optical pre-amplifier that may amplify upstream signals. The optical pre-amplifier may also be an EDFA. The optical pre-amplifier may amplify upstream signals based on the length of the fiber between the outside plant and the OCML headend to account for any loses in the strength of the upstream signals propagating along the fiber. The gain of the optical pre-amplifier may be based at least in part on a required signal strength of the upstream signals at an input to the DWDM passive circuit, in order for the DWDM to demultiplex the upstream signals. The optical pre-amplifier may have the effect of amplifying a multi-wavelength optical data signal, so that the one or more optical data signals in the multi-wavelength optical data signal, each of which have different respective wavelengths, have a certain received power level at a DWDM passive circuit upstream input port. 
     The optical signal to noise ratio (OSNR) of the EDFA may be based at least in part on an input power to the EDFA, a noise figure. In some embodiments the OSNR of the EDFA may be determined by the expression OSNR=58 dB−NF−P in , where NF is the noise floor, P in  is the input power to the EDFA. 58 dB is constant that is based on Planck&#39;s constant, the speed of light, the bandwidth of the EDFA, and the wavelength of the one or more packets of light. In some embodiments, the OSNR of the EDFAs disclosed herein may be as high as 40 dB, for one or more packets of light that are transmitted downstream from OCML headend. The OSNR of the transceivers disclosed herein may be as low as 23 dB, and there may be a plurality of bit error rate (BER) values associated with this 23 dB OSNR. The BER may be determined based at least in part on the energy detected per bit, noise power spectral density, and a complementary error function. More specifically the BER may 
                 1   2     ⁢     erfc   ⁡   (         E   b       N   0         )       ,         
wherein E b  is the energy detected per bit, N 0  is the noise power spectral density, and erfc is the complementary error function. For instance, the transceivers disclosed herein may be able to achieve a BER of 10 −12  when the common logarithm ratio of received power to 1 milliwatt (mW) is −23 dBm. For example, a transceiver in the OCML headend may receive an upstream flow or one or more packets of light, from a transceiver in the field hub or outside plant, that has a common logarithm ratio of received power per mW of −23 dBm. The BER may be greater for common logarithm ratios of received power per mW, meaning that the BER may decrease with the higher common logarithm ratios of received power per mW. The transceivers may be configured to have greater OSNRs, and therefore lower BERs for the same value of a common logarithm ratio of received power per mW. For example, a first transceiver configured to have an OSNR of 24 dB with a common logarithm ratio of received power per mW of −28 dBm may have an approximate BER of 10 −5  and a second transceiver configured to have an OSNR of 26 dB with a common logarithm ratio of received power per mW of −28 dBm may have an approximate BER of 10 −7 . Thus, transceivers configured to have a higher OSNR results in the transceiver having a lower BER for the same common logarithm ratio of received power per mW.
 
     The OCML headend may also comprise an optical switch that may connect a WDM to a primary optical fiber connecting the OCML passive circuit to the outside plant. The optical switch may also connect the WDM to a secondary optical fiber connecting the OCML passive circuit to the outside plant. The optical switch may be in a first position that connects the WDM to the primary optical fiber, and may be in a second position that connects the WDM to the secondary optical fiber. The optical switch may be in the second position when the primary optical fiber is disconnected or unresponsive. 
     Because the OCML headend, field hub or outside plant, and fiber connecting the OCML headend and field hub or outside plant mainly comprise passive optical components, in comparison to other optical ring networks that primarily have active components, one or more devices may be needed to control for dispersion of light as it goes through different optical components. In particular, as packets of light traverse the different optical components in the OCML headend (e.g., WDMs and/or optical amplifiers including booster amplifiers or pre-optical amplifiers), an optical data signal being carried by the packets of light may begin to experience temporal broadening which is a form of optical data signal distortion. Because the OCML systems disclosed herein transmit high data rate optical data signals, about 10 Gbps, there may be some strong dispersive temporal broadening effects introduced by one or more of the optical components in the OCML headend. The optical data signals disclosed herein may carry digital symbols, which are a series of binary digits (1 or 0), and each binary digit may be represented by a pulse of light (one or more packets of light) of a certain amplitude, that lasts a certain period. For example, an optical data signal may be carrying a plurality of digital symbols, wherein a pulse of light that has a certain amplitude and certain pulse width (certain period) represents each binary digit in a digital symbol of the plurality of digital symbols. The pulse widths of each of the pulses of light may begin to broaden as each of the pulses of light traverses different optical components. As a result, the symbol may begin to broaden. Consequently, as each of the symbols begins to broaden in time, and may become indistinguishable from an adjacent symbol. This may be referred to as intersymbol interference (ISI), and can make it difficult for a fiber-optic sensor or photodetector receiving the optical data signal to distinguish adjacent symbols from one another. In order to compensate for this phenomenon, a dispersion compensation module (DCM) may be inserted between one or more optical components in the OCML headend. For example, a DCM may be receive an optical data signal output from a WDM to compensate for any potential ISI that may be introduced as a result of different optical data signals, carried over pulses of light, that have been combined, multiplexed, or circulated in the WDM. The DCM can also compensate for dispersion characteristics of the fiber between the OCML headend and the field hub or outside plant. In particular, the fiber may comprise certain optical elements or material impurities that can be compensated for in the DCM, wherein the DCM comprises long pieces of dispersion-shifted fibers or chirped fiber Bragg gratings. The dispersion-shifted fibers or chirped fiber Bragg gratings can reduce ISI that is introduced by the fiber. In some embodiments, the OCML headend may comprise one or more DCMs to compensate for ISI that may be introduced by one or more optical components in the OCML headend or fiber that is either upstream or downstream from the one or more DCMs. For example, in one embodiment, a first DCM may be positioned downstream from a first WDM and a second DCM may be positioned upstream from a second DCM. This embodiment is illustrated in  FIG.  1   , and further explained below. 
     It should be noted that the DCMs may cause negative dispersion for shorter lengths of fiber (e.g., lengths of fiber less than 5 kilometers). Negative dispersion may occur when a flow of one or more packets of light, forming a wave, propagate along a distance of the fiber with a negative rate of change. The wave propagates along the fiber, and the wave has an electric field associated with it that is normal to the direction of propagation of the wave, and a magnetic field associated with it that is normal to the electric field and the direction of propagation of the wave. The wave propagates along the fiber with an angular frequency, ω, which may be a function of a propagation constant β. The electric and magnetic fields may both oscillate in accordance with sinusoidal function e i(βz−ωt) , wherein z is a distance that the wave has traveled in the fiber, and t is the time elapsed after the wave has been transmitted by the DCM. That is the electric and magnetic field may oscillate in accordance with a sinusoidal function equal to cos(βz−ωt)+i sin(βz−ωt), wherein the oscillation of the wave is based at least in part on the propagation constant, and angular frequency, and the amount of time that has elapsed since the wave has been transmitted by the DCM. The angular frequency may be reciprocal of the amount of time that the electric and magnetic fields oscillate an entire cycle or period. The propagation constant may be a complex quantity, wherein the real part of the propagation constant is a measure of a change in the attenuation of the wave as it propagates along the fiber. The real part of the propagation constant may be referred to as an attenuation constant. The imaginary part of the propagation constant is a measure of a change in the phase of the wave as it propagates along the fiber. Because the angular frequency may be based at least in part on the propagation constant, the angular frequency of the wave may change as the attenuation and phase of the wave change. Accordingly, the velocity of the wave may change as it propagates along the fiber and may begin to experience dispersion. The velocity of the wave may be the rate at which the angular frequency changes as the propagation constant changes while the wave propagates along the fiber. That is the velocity of the wave may be expressed as 
             v   =         d   ⁢   ω       d   ⁢   β       .           
The wavelength of the wave may be expressed as
 
               λ   =     2   ⁢   π   ⁢     c   ω         ,         
wherein c is the speed of light. The dispersion of the wave may be based at least in part on the speed of light, wavelength of the wave, velocity of the wave, and the rate of change of the velocity of the wave with respect to the angular frequency. The dispersion of the wave may be expressed as
 
             D   =         2   ⁢   π   ⁢   c         v   2     ⁢     λ   2         ⁢         d   ⁢   v       d   ⁢   ω       .             
is a dispersion parameter of the wave and is based on the speed of light (c), the velocity of the wave (ν), the wavelength of the wave (λ), and the rate of change or first derivative of the velocity of the wave with respect to the angular frequency of the wave
 
               (       d   ⁢   v       d   ⁢   ω       )     .         
The dispersion parameter indicates whether the wave experiences positive dispersion (temporal broadening) or negative dispersion (temporal contraction) as the wave propagates along the fiber. Negative dispersion may occur when the rate of change or derivative of the velocity of the wave, with respect to the angular frequency is negative. When
 
             (       d   ⁢   v       d   ⁢   ω       )         
is negative, the wave is said to be experiencing negative dispersion. Thus when the rate of change of the velocity of the wave with respect to the angular frequency is negative, the wave may experience temporal contraction. Accordingly, transceivers in the transponders of the DWDM of the field hub or outside plant must be capable of detecting waves subject to negative dispersion. Negative dispersion is the opposite of positive dispersion in that ISI may not occur when a wave is detected at the transceivers in the transponders of the DWDM of the field hub or outside plant. However, temporal contraction of the wave may make it difficult for a fiber-optic sensor or photodetector to detect an optical data signal carrying digital symbols, because the digital symbols in the optical data signal may begin to overlap with one another. This may happen because each of the digital symbols are a series of binary digits, and the binary digits are represented by a pulse of light (one or more packets of light in the wave), and as the wave begins to experience negative dispersion, each of the binary digits may begin to overlap with one another. The transceivers disclosed herein are equipped with fiber-optic sensors or photodetectors that are capable of correctly detecting the one or more packets of light in the wave, when the wave is subject to positive and/or negative dispersion. The DCMs disclosed herein may transmit a signal a distance of 30 kilometers.
 
     The OCML headend may also comprise a non-optical switch that switches due to a loss of light or on demand. 
     The OCML headend may also comprise wavelength-monitoring ports that connect to the primary and secondary optical fibers to monitor the wavelength of upstream signals comprising 10 GbE, GPON, and/or XGPON/10GEPON signals and/or to monitor the wavelength of downstream signals comprising 10 GbE, GPON, and/or XGPON/10GEPON signals. 
     Certain embodiments of the disclosure are directed to an OCML, systems, and methods. Embodiments of the disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art Like numbers refer to like elements throughout. 
     It should be noted that the OCML headend may also be referred to as a terminal or Master Terminal Center (MTC). In some embodiments, the OCML headend may be collocated within the MTC. In other embodiments, the OCML headend may be located at a secondary transport center (STC) that may be connected to the MTC via a network. In some embodiments, an outside plant may also be referred to as a field hub or remote physical device (RPD). In some embodiments, the outside plant may be collocated with the RPD. In other embodiments, the outside plant and RPD may not be collocated and connected via a 10 Gigabit transceiver. The outside plant may comprise one or more passive optical network devices. 
       FIG.  1    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  1   , headend  101  is a smart integrated OCML headend, which is a circuit, comprising one or more EDFAs (e.g., Optical amplifiers  102  and  104 ), a DWDM (e.g., DWDM  106 ), one or more WDMs (e.g., WDM  108  and  110 ), one or more DCMs (e.g., DCM  112  and  114 ), and an optical switch  116  to feed a primary optical fiber (e.g., Primary Fiber  176 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  174 ). The disclosure provides a method of transporting multiple 10 GbE and GPON/XGPON/10GEPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s MTC facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     In one aspect, headend  101  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  190 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  188 ). 20×10 GbE DS  190  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  188  may receive upstream data over 10 GbE wavelengths. Headend  101  may comprise two PON  124  connectors, one of which may be a GPON connector (e.g., GPON  184 ) and one of which may be an XGPON/10GEPON connector (e.g., XGPON/10GEPON  182 ). Headend  101  may also comprise two wavelength-monitoring ports (e.g., wavelength-monitoring ports  126 ), a primary optical fiber (e.g., primary optical fiber  176 ) and a secondary optical fiber (e.g., secondary optical fiber  174 ) that transmit and receive a plurality of multi-wavelength 10 GbE and GPON/XGPON/10GEPON optical signals. Primary optical fiber  176  and secondary optical fiber  174  may transmit a first plurality of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON optical signals from headend  101  to a outside plant (not illustrated in  FIG.  1   ), and may receive a second plurality of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON optical signals from the outside plant. 
     In some embodiments, 20×10 GbE DS  190  and 20×10 GbE UP  188  may comprise connectors belonging to the laser shock hardening (LSH) family of connectors designed to transmit and receive optical data signals between DWDM  106 , and one or more cable company servers (not shown). In other embodiments, 20×10 GbE DS  190  and 20×10 GbE UP  188  may also comprise E2000 connectors, and may utilize a 1.25 millimeter (mm) ferrule. 20×10 GbE DS  190  and 20×10 GbE UP  188  may be installed with a snap-in and push-pull latching mechanism, and may include a spring-loaded shutter which protects the ferrule from dust and scratches. The shutter closes automatically once the connector is disengaged, locking out impurities, which could later result in network failure, and locking in possibly damaging lasers. 20×10 GbE DS  190  and 20×10 GbE UP  188  may operate in a single mode or a multimode. 
     In single mode, 20×10 GbE DS  190  and 20×10 GbE UP  188  only one mode of light may be allowed to propagate. Because of this, the number of light reflections created as the light passes through the core of single mode 20×10 GbE DS  190  and 20×10 GbE UP  188  decreases, thereby lowering attenuation and creating the ability for the optical data signal to travel further. Single mode may be for use in long distance, higher bandwidth connections between one or more cable company servers and DWDM  106 . 
     In multimode, 20×10 GbE DS  190  and 20×10 GbE UP  188 , may have a large diameter core that allows multiple modes of light to propagate. Because of this, the number of light reflections created as the light passes through the core increase, creating the ability for more data to pass through at a given time. Multimode 20×10 GbE DS  190  and 20×10 GbE UP  188 , may generate high dispersion and a attenuation rate, which may reduce the quality of an optical data signal transmitted over longer distances. Therefore multimode may be used to transmit optical data signals over shorter distances. 
     In one aspect, headend  101  can transmit and receive up to twenty bi-directional 10 GbE optical data signals, but the actual number of optical data signals may depend on operational needs. That is, headend  101  can transport more or less than twenty 10 GbE downstream optical signals, or more or less than twenty 10 GbE upstream optical data signals, based on the needs of customers&#39; networks (e.g., Remote PHY Network  216 , Enterprise Network  218 , Millimeter Wave Network  214 ). These customer networks may be connected to headend  101  through an optical ring network (e.g., metro access optical ring network  206 ). 
     The operation of headend  101  may be described by way of the processing of downstream optical data signals transmitted from headend  101  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  190  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  190  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  190  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  106  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  98 ) comprising the twenty corresponding second optical data signals onto a fiber. More specifically, DWDM  106  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength downstream optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  198 , may be input to a WDM (e.g. WDM  108 ). WDM  108  may be a three port wave division multiplexer (WDM), or a three port circulator, that receives 10 GbE DS  198  on port  194  and outputs 10 GbE DS  198  on port  186  as 10 GbE DS  172 . 10 GbE DS  172  may be substantially the same as 10 GbE DS  198  because WDM  108  may function as a circulator when 10 GbE DS  172  is input on port  194 . 
     10 GbE DS  172  may be input into a DCM (e.g., DCM  112 ) to compensate for dispersion that 10 GbE DS  172  may experience after being amplified by an EDFA and multiplexed by a WDM, with other optical data signals, that are downstream from the DCM. The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  101  over a fiber connecting headend  101  to a field hub or outside plant. In some embodiments, DCM  112  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  112  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  112  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. 
     DCM  112  may input 10 GbE DS  172  and may output 10 GbE DS  170  to an EDFA (e.g., booster optical amplifier  102 ). A gain of the booster optical amplifier (e.g., booster optical amplifier  102 ) may be based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, the gain of booster optical amplifier  102  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of booster optical amplifier  102  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  176  and/or the length of secondary fiber  174 ). 10 GbE DS  170  may be amplified by booster optical amplifier  102 , and booster optical amplifier  102  may output 10 GbE DS  178  to port  164  of WDM  110 . 
     WDM  110  may be a WDM that may multiplex 10 GbE DS  178  with one or more PON signals (e.g., XGPON/10GEPON  182  and GPON  184 ). 10 GbE DS  178  may be a multi-wavelength optical data signal, wherein the wavelengths comprise the same wavelengths as 10 GbE DS  198 . In some embodiments, the wavelengths of the multi-wavelength optical data signal 10 GbE DS  178  may be within the conventional c band of wavelengths, which may include wavelengths within the 1520 nm-1565 nm range. XGPON/10GEPON  182  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1582 nm range. GPON  184  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm. The XGPON/10GEPON optical signal may be input to WDM  110  on port  162  and the GPON signal may be input to WDM  110  on port  160 . WDM  110  outputs an egress optical data signal from port  156 , which may be a multi-wavelength optical data signal comprising 10 GbE, signals. WDM  110  may multiplex 10 GbE DS  178 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  106  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  152 ) may be output on port  158  of WDM  110  and optical switch  116  may switch egress optical data signal  152  out of connector  118  or connector  150 . In some embodiments, connector  118  may be a primary connector and connector  150  may be a secondary connector or a backup connector. Wavelength monitoring connector  146  may connect connector  118  to a first port of wavelength-monitoring ports  126 , and wavelength monitoring connector  148  may connect connector  150  to a second port of wavelength-monitoring ports  126 . Wavelength-monitoring ports  126  may monitor the wavelengths in egress optical data signal  152  via connector  146  or connector  148  depending on the position of switch  116 . Egress optical data signal  152  may exit headend  101  either via connector  144  connected to primary fiber  176  or via connector  142  connected to secondary fiber  174  depending on the position of switch  116 . Egress optical data signal  152  may be transmitted on primary fiber  176  to a first connector in the field hub or outside plant, or may be transmitted on secondary fiber  174  to a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     The operation of headend  101  may be described by way of the processing of upstream optical data signals received at headend  101  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, XGPON/10GEPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  176  or secondary fiber  174  depending on the position of switch  116 . Because the multi-wavelength ingress optical data signal is routed to port  158  of WDM  110 , and is altered negligibly between connector  144  and port  158  or connector  142  and port  158 , depending on the position of switch  116 , the multi-wavelength ingress optical data signal may be substantially the same as ingress optical data signal  154 . The multi-wavelength ingress optical data signal may traverse connector  118  and switch  116 , before entering WDM  110  via port  158  if switch  116  is connected to connector  118 . The multi-wavelength ingress optical data signal may traverse connector  150  and switch  116 , before entering WDM  110  via port  158  if switch  116  is connected to connector  150 . WDM  110  may demultiplex one or more 10 GbE optical data signals, XGPON/10GEPON optical data signals, and/or GPON optical data signals from ingress optical data signal  154 . WDM  110  may transmit the one or more XGPON/10GEPON optical data signals along XGPON/10GEPON  182  to one of PON connectors  124  via port  162 . WDM  110  may transmit the one or more GPON optical data signals along GPON  184  to one of PON connectors  124  via port  160 . WDM  110  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  180 ) out of port  156  to DCM  114 . 
     In some embodiments, DCM  114  may be configured to balance positive and/or negative dispersion that may be introduced to a SONET/SDH egress optical data signal that may exit headend  101  from 20×10 GbE UP  188 . The SONET/SDH egress optical data signal may be an upstream signal from a field hub or outside plant destined for a MTC. For example, a customer premise may be connected to the field hub or outside plant and may send one or more packets via a SONET/SDH network to the field hub or outside plant which may in turn transmit the one or more packets using 10 GbE optical data signals to headend  101 . The one or more packets may be destined for a company web server connected to the MTC via a backbone network. Because headend  101  may be collocated in a STC that is connected to the MTC via an optical ring network, wherein the connection between the STC and MTC is an SONET/SDH optical network connection, DCM  114  may be configured to compensate for positive and/or negative dispersion on the SONET/SDH optical network connection. That is DCM  114  may be configured to reduce temporal broadening of the SONET/SDH ingress optical data signal or temporal contraction of the SONET/SDH ingress optical data signal. DCM  114  may input 10 GbE UP  180  and may output 10 GbE UP  166  to an input of EDFA (e.g., optical pre-amplifier  104 ). 
     A gain of optical pre-amplifier  104  may be based at least in part on a distance that the SONET/SDH egress optical data signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment on the SONET/SDH optical network connection. For instance, the gain of optical pre-amplifier  104  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of optical pre-amplifier  104  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of the fiber of the SONET/SDH optical network connection). 10 GbE UP  166  may be amplified by optical pre-amplifier  104 , and optical pre-amplifier  104  may output 10 GbE UP  168  to WDM  108 . 
     The wavelength of 10 GbE UP  168  may be within the conventional c band of wavelengths, which may include wavelengths within the 1520 nm-1565 nm range. The one or more XGPON/10GEPON optical data signals may have a wavelength within the 1571 nm-1582 nm range, and the one or more GPON optical data signals may have a wavelength of 1490 nm. 
     WDM  108  may receive 10 GbE UP  168  on port  192 , and may output 10 GbE UP  168  on port  194  as a multi-wavelength upstream optical data signal (e.g., 10 GbE UP  196 ). 10 GbE UP  196  is substantially the same as 10 GbE UP  168  because WDM  108  may function as a circulator when 10 GbE UP  168  is input to port  192 . 10 GbE UP  196  may be received by DWDM  106 , and DWDM may demultiplex one or more 10 GbE optical data signals from 10 GbE UP  196 . Because 10 GbE UP  196  is a dispersion compensated amplified version of the multi-wavelength ingress optical data signal, DWDM  106  may demultiplex the one or more optical data signals into individual optical data signals in accordance with the individual wavelengths of any 10 GbE optical data signals in the multi-wavelength ingress optical data signal. More specifically, 10 GbE UP  196  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  106  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  188 . Each of the transponders of 20×10 GbE UP  188  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  188  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  2    depicts a network architecture, in accordance with the disclosure. The network architecture may comprise a MTC Master Terminal Facility (for example MTC Master Terminal Facility  201 ) that may connect a cable company to the Internet through a backbone network (for example Backbone Network  202 ). MTC Master Terminal Facility  201  may include one or more servers hosting content that may be consumed by customer devices connected to the one or more servers via one or more networks. For example, the one or more networks may include cellular or millimeter wave networks (for example Millimeter Wave Network  214 ), remote physical networks (for example Remote PHY Network  216 ), enterprise networks (for example Enterprise Network  218 ), and one or more passive optical networks (PON) (for example PON  222  and PON  242 ). MTC Master Terminal Facility  201  may be connected to these one or more networks via one or more optical fibers (for example Primary Optical Fiber  211  and Secondary Optical Fiber  213 ). MTC Master Terminal Facility  201  may connect to the one or more optical fibers via an OCML terminal (for example, OCML terminal  207 ), and the one or more networks may connect to the one or more optical fibers via a MDM (for example MDM  208 ) comprising multiplexer-demultiplexer (for example DMux  288 ), and PON port (for example PON  298 ). OCML  207 , Primary Optical Fiber  211 , Secondary Optical Fiber  213 , and MDM  208  form a network that may be referred to as the Metro Access Optical Ring Network (for example Metro Access Optical Ring Network  206 ). DMux  288  may multiplex optical data signals received from the one or more networks and transmit the multiplexed optical data signals to OCML  207 . Conversely DMux  288  may demultiplex optical data signals received from OCML  207  and transmit the demultiplexed optical data signals to the one or more networks. Millimeter Wave Network  214  may be connected to DMux  288  via connection  254 . Remote PHY Network  216  may be connected to DMux  288  via connection  256 . Enterprise Network  218  may be connected to DMux  288  via connection  258 . PON  222  may be connected to DMux  288  via connection  251 . PON  242  however may be connected to PON  298  via connection  253 . 
     Millimeter Wave Network  214  may comprise one or more cellular or Wi-Fi masts with one or more modems (for example Modem  212 ) that provide mobile devices (for example devices  215 ) with access to content hosted by the one or more servers at MTC Master Terminal Facility  201 . 
     Remote PHY Network  216  may comprise a remote physical (PHY) node (for example Remote PHY Node  207 ) that may comprise an optical communications interface that connects to connection  256  and a cable interface that connects to one or more cable devices (for example devices  217 ) via cables  226 -cable  236 . The one or more cable devices may be devices connecting cable set-top boxes in one or more residential, commercial, or industrial buildings to a tap at devices  217 . 
     Enterprise Network  218  may comprise one or more offices requiring high-speed access to the Internet via Backbone Network  202  for example. Enterprise Network  218  may connect to the Internet via connection  258 . 
     PON  222  may comprise one or more PON devices (for example devices  299 ) that require access to MTC Master Terminal Facility  201  or the Internet via for Backbone Network  202  for example. Devices  299  may be connected to a splitter (for example Splitter  223 ) via connections  225 -connection  227 . Splitter  223  is an optical splitter that may combine one or more optical data signals from each of devices  299  and transmit them to Strand PON optical line terminal (OLT)  210  via connection  252 . Splitter  223  may also separate one or more optical data signals received from Strand PON OLT  210  via connection  252  into one or more optical data signals for each of devices  299 . Strand PON OLT  210  may be an OLT that connects optical network units (ONUs) at a customer premises to DMux  288 . Because one or more optical data signals can be transmitted as a multiplexed signal on a single strand of fiber, Strand PON OLT  210  may be connected to other PONs (not shown), in addition to PON  222 , and may combine optical data signals received from the PONs and transmit the combined optical data signals to DMux  288 . Strand PON OLT  210  may separate optical data signals received from DMux  288  into corresponding optical data signals each of which is for transmission to a corresponding PON. 
     PON  242  may comprise one or more PON devices (for example devices  249 ) that require access to MTC Master Terminal Facility  201  or the Internet via for Backbone Network  202  for example. Devices  249  may be connected to a splitter (for example Splitter  243 ) via connections  245 -connection  247 . Splitter  243  is an optical splitter that may combine one or more optical data signals from each of devices  249  and transmit them to PON  298  via connection  253 . Splitter  243  may also separate one or more optical data signals received from PON  298  via connection  253  into one or more optical data signals for each of devices  249 . 
       FIG.  3    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure.  FIG.  3    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  3   , headend  330  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  307 ), a WDM (e.g., WDM  305 ), a GPON port (e.g., GPON PORT  301 ), an XGPON/10GEPON port (e.g., XGPON/10GEPON PORT  303 ), and an optical switch  308  to feed a primary optical fiber (e.g., Primary Fiber  309 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  311 ). DWDM  307  may be similar in functionality to DWDM  106  and WDM  305  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE, GPON, and/or/XGPON/10GEPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and an outside plant (e.g., Outside plant  350 ). The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to an outside plant or field hub which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     In one aspect, headend  330  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  304 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  306 ). 20×10 GbE DS  304  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  306  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  304  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  306  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  330  may be described by way of the processing of downstream optical data signals transmitted from headend  330  to an outside plant (e.g., Outside plant  350 ), and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  304  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  304  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  304  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  307  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g.,  336 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal  336  may be a 10 GbE optical data signal. More specifically, DWDM  307  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal  336 , may be input to a WDM (e.g. WDM  305 ). WDM  305  may be a four port wave division multiplexer (WDM), or a four port circulator, that receives multi-wavelength downstream optical data signal  336  on port  321 . WDM  305  may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  334 ), on port  302 , a GPON signal, carried on a second fiber (e.g., GPON  332 ), on port  322 , and may multiplex multi-wavelength downstream optical data signal  336  with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  334  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm and 1260 nm-1280 nm range. GPON  332  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm and 1310 nm. WDM  305  outputs an egress optical data signal from port  324 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  305  may multiplex multi-wavelength downstream optical data signal  336 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  307  multipleyxes optical data signals. The egress optical data signal (e.g., egress optical data signal  338 ) may be output on port  324  of WDM  305  and optical switch  308  may switch egress optical data signal  338  onto primary fiber  309  or secondary fiber  311  depending on the position of switch  308 . Egress optical data signal  338  may be transmitted on primary fiber  309  to a first connector at outside plant  350 , or may be transmitted on secondary fiber  311  to a second connector at outside plant  350 . Outside plant  350  may include a MDM with the first connector and the second connector. 
     The operation of outside plant  350  may be described by way of the processing of a downstream optical data signal received from headend  330 . Egress optical data signal  338  may be received on the first or second connector at outside plant  350  based on a position of optical switch  380 , as ingress optical data signal  356 . That is ingress optical data signal  356  may be similar to egress optical data signal  338 . Ingress optical data signal  356  may be received by WDM  313  via port  372 . WDM  313  may demultiplex ingress optical data signal  356  into a multi-wavelength downstream optical data signal  359 , an XGPON/10GEPON optical data signal that may be output on port  392  onto a first fiber (e.g., XGPON/10GEPON  354 ), and/or a GPON optical data signal output on port  382  onto a second fiber (e.g., GPON  352 ). The XGPON/10GEPON optical data signal may be received on XGPON/10GEPON port  353  and the GPON optical data signal may be received on GPON port  351 . 
     The multi-wavelength downstream optical data signal  359  may be output on port  362  and received by DWDM  315  which may be an array waveguide gratings (AWG) or TFF. The multi-wavelength downstream optical data signal  359  may comprise 10 GbE optical data signals. DWDM  315  may demultiplex the multi-wavelength downstream optical data signal  359  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength downstream optical data signal  359  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  315  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  312 . Each of the transponders of 20×10 GbE DS  312  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. In some embodiments, DWDM  315  may output one or more 10 GbE optical data signals (e.g., RPD DS  327 ) to a remote physical (PHY) device (RPD) (e.g., RPD  317 ). RPD  317  may be similar to Remote PHY Node  207  in functionality. RPD  317  may convert the one or more 10 GbE optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. RPD  317  may also convert one or more electrical signals into one or more 10 GbE optical data signal for transmission to a transponder (e.g., 20×10 GbE UP  314 ). 
     The operation of outside plant  350  may be further described by way of the processing of a upstream optical data signal transmitted to headend  330 . Each of the transponders of 20×10 GbE UP  314  may receive a SONET/SDH optical data signal from one or more devices providing cable to customers or subscribers to a cable&#39;s services. For example, the one or more devices may be any of devices  217 , and RPD  327  may be connected to devices  217  via cable  226  . . . cable  236 . Cable  226  . . . cable  236  may be coaxial cables. Each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  314  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  314  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  315  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g.,  358 ) comprising the twenty corresponding second optical data signals onto a fiber. In some embodiments, RPD  317  may transmit one or more 10 GbE optical data signals (e.g., RPD DS  331 ) to one or more of 20×10 GbE UP  314 . RPD DS  331  may be 10 GbE optical data signals that generated by RPD  317  in response to RPD  317  receiving electrical signals on coaxial cables connecting a remote physical (PHY) network (e.g., remote PHY network  216 ) to DWDM  315 . The multi-wavelength downstream optical data signal  358  may be a 10 GbE optical data signal. More specifically, DWDM  315  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal  358 , may be input to a WDM (e.g. WDM  313 ). WDM  313  may be a four port wave division multiplexer (WDM), or a four port circulator, that receives multi-wavelength downstream optical data signal  358  on port  362 . WDM  313  may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  354 ), on port  392 , a GPON signal, carried on a second fiber (e.g., GPON  352 ), on port  382 , and may multiplex multi-wavelength downstream optical data signal  358  with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  354  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm and 1260 nm-1280 nm range. GPON  352  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm or 1310 nm. WDM  313  outputs an egress optical data signal from port  372 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  313  may multiplex multi-wavelength downstream optical data signal  358 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  307  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  357 ) may be output on port  372  of WDM  313  and optical switch  380  may switch egress optical data signal  357  onto primary fiber  309  or secondary fiber  311  depending on the position of switch  380 . Egress optical data signal  357  may be transmitted on primary fiber  309  to a first connector at headend  330 , or may be transmitted on secondary fiber  311  to a second connector at headend  330 . 
     The operation of headend  330  may be further described by way of the processing of an upstream optical data signal received from outside plant  350 . Egress optical data signal  357  may be received on the first or second connector at headend  330  based on a position of optical switch  308 , as ingress optical data signal  339 . That is ingress optical data signal  339  may be similar to egress optical data signal  357 . Ingress optical data signal  339  may be received by WDM  305  via port  324 . WDM  305  may demultiplex ingress optical data signal  339  into a multi-wavelength upstream optical data signal  337 , an XGPON/10GEPON optical data signal that may be output on port  302  onto a first fiber (e.g., XGPON/10GEPON  334 ), and/or a GPON optical data signal output on port  322  onto a second fiber (e.g., GPON  332 ). The XGPON/10GEPON optical data signal may be received on XGPON/10GEPON port  303  and the GPON optical data signal may be received on GPON port  301 . 
     The multi-wavelength upstream optical data signal  339  may be output, as multi-wavelength upstream optical data signal  337 , on port  321  and received by DWDM  307 . The multi-wavelength upstream optical data signal  337  may comprise 10 GbE optical data signals. DWDM  307  may demultiplex the multi-wavelength upstream optical data signal  337  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength upstream optical data signal  337  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  307  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  306 . Each of the transponders of 20×10 GbE UP  306  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  306  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  4    shows an access link loss budget of a Dense Wave Division Multiplexing (DWDM) passive circuit, in accordance with the disclosure. Link loss budget  400  illustrates the link loss budget in decibels (dB) associated with a physical optical link connecting an OCML transceiver to an outside plant transceiver. The OCML headend and outside plant transceiver may comprise 10 GbE transceivers that may not contribute to the loss budget. That is there may be no power lost when the 10 GbE transceivers transmit a 10 GbE optical data signal. Thus, Txcvr Pwr/WL  401  may be equal to 0.0 when a transceiver at an OCML headend transmits a 10 GbE optical data signal to an outside plant transceiver, and when the transceiver at the outside plant transmits a 10 GbE optical data signal to the OCML terminal. The transceiver in the OCML headend may be similar to a transceiver included in the transponders disclosed herein (e.g., 20×10 GbE DS  190  or 20×10 GbE UP  188  in headend  101  or 20×10 GbE DS  304  or 20×10 GbE UP  306  in OCML headend  301 ). The transceiver in the outside plant may be similar to a transceiver included in the transponders disclosed herein (e.g., 20×10 GbE DS  312  or 20c10 GbE UP  314 ). 
     In some embodiments, the fiber connecting the transceiver at the OCML headend to the outside plant, may be 5 kilometers (km). Thus fiber  402  may be 5 km in length and when a transceiver in the OCML headend transmits an optical data signal (e.g., 10 GbE optical data signal) to a transceiver in the outside plant along fiber  402 , fiber  402  may cause the optical data signal to experience a 1.25 dB loss. Similarly, when the transceiver in the outside plant transmits an optical data signal to the OCML headend along fiber  402 , fiber  402  may cause the optical data signal to experience a 11.25 dB loss. 
     In some embodiments, a multiplexer in a DWDM (e.g., DWDM  106  or DWDM  307 ) in an OCML headend may contribute to the loss budget. This may be based at least in part on the multiplexing process applied to multiple input optical data signals received from multiple transponders (e.g., 20×10 GbE DS  190  or 20×10 GbE DS  304 ). The multiplexing process may result in the multiplexed optical data signal having less power than the multiple input optical data signals. The OCML headend in some embodiments, may also be referred to as the headend, and thus headend DWDM mux  403  is the loss budget associated with the multiplexing of multiple input optical data signals. The loss budget for headend DWDM mux  403  may be 5.8 dB. Similarly a demultiplexer in a DWDM in an outside plant may contribute to the loss budget. This may be based at least in part on the demultiplexing process applied to a multiplexed optical data signal received from the DWDM in the headend. The demultiplexing process may result in each of the demultiplexed optical data signals, included in the received multiplexed optical data signal, having less power than the received multiplexed optical data signal. Thus the loss budget for field DWDM DeMux  404  may be 5.8 dB. 
     In some embodiments, an optical switch (e.g., optical switch  116  or optical switch  308 ) may contribute to the loss budget experienced by an optical data signal is transmitted from the OCML headend to the outside plant or an optical data signal received at the OCML headend from the outside plant. This may be due to the fact that the optical switch may comprise one or more electronics that may cause the optical data signal to experience some loss in power as it is switched from one connector to another in the OCML headend. Thus switch (headend)  405  may cause the optical data signal to experience a 1.5 dB loss. 
     In some embodiments, there may be an optical passive component connecting the OCML headend to the outside plant. For instance, there may be a first fiber connection between the OCML headend and the optical passive component, and a second fiber connection between the optical passive component and the outside plant. This is depicted as passive optical component  625  in  FIG.  6    below. The optical passive component, may cause optical data signals transmitted between the OCML headend and the outside plant to experience some loss in power. The optical passive component may be a 3 dB optical passive component (i.e., 3 dB optical passive  406 ) that may cause the optical data signals to experience a 3.5 dB loss. 
     In some embodiments, there may be two connectors at the OCML headend (e.g., connector  118  and connector  150 ). Each may cause an optical data signal sent to an outside plant or received from the outside plant to experience a loss in power. Each connector may contribute a 0.3 dB loss resulting in the two connectors (connectors  407 ) contributing a total loss of 0.6 dB. 
     In some embodiments, a safety margin (e.g., safety margin  408 ) of 3 dB may be included.) 
       FIG.  5    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure.  FIG.  5    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  5   , headend  530  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  507 ), a first WDM (e.g., WDM  505 ), a second WDM (e.g., WDM  509 ), a GPON port (e.g., GPON PORT  501 ), an XGPON/10GEPON port (e.g., XGPON/10GEPON PORT  503 ), an EDFA (e.g., EDFA  541 ), and an optical switch  508  to feed a primary optical fiber (e.g., Primary Fiber  540 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  511 ). DWDM  507  may be similar in functionality to DWDM  106  and WDM  505  and WDM  509  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE and GPON/XGPON/10GEPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and an outside plant (e.g., Outside plant  550 ) or field hub. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     In one aspect, headend  530  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  504 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  506 ). 20×10 GbE DS  504  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  506  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  504  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  506  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  530  may be described by way of the processing of downstream optical data signals transmitted from headend  530  to an outside plant (e.g., Outside plant  550 ), and the processing of upstream optical data signals received from the outside plant. Each of the transponders of 20×10 GbE DS  504  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  504  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  504  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  507  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., multi-wavelength downstream optical data signal  547 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal  547  may be a 10 GbE optical data signal. More specifically, DWDM  507  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal  547 , may be input to WDM  505 . WDM  505  may be a four port wave division multiplexer (WDM), or a four port circulator, that receives multi-wavelength downstream optical data signal  547  on port  542 . WDM  505  may function as a circulator and may output multi-wavelength downstream optical data signal  538 , on port  540 , to WDM  509 . Multi-wavelength downstream optical data signal  538  may be substantially the same as multi-wavelength downstream optical data signal  547 . WDM  509  may receive multi-wavelength downstream optical data signal  538 , and may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  534 ), on port  548 , a GPON signal, carried on a second fiber (e.g., GPON  532 ), on port  549 , and may multiplex multi-wavelength downstream optical data signal  538  with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  534  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm and 1260 nm-1280 nm range. GPON  532  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 or 1310 nm. WDM  509  outputs an egress optical data signal from port  542 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  509  may multiplex multi-wavelength downstream optical data signal  538 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  307  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  539 ) may be output on port  542  of WDM  509  and optical switch  508  may switch egress optical data signal  539  onto primary fiber  540  or secondary fiber  511  depending on the position of switch  508 . Egress optical data signal  539  may be transmitted on primary fiber  540  to a first connector at outside plant  550 , or may be transmitted on secondary fiber  511  to a second connector at outside plant  550 . Outside plant  550  may include a MDM with the first connector and the second connector. 
     The operation of outside plant  550  may be described by way of the processing of a downstream optical data signal received from headend  530 . Egress optical data signal  539  may be received on the first or second connector at outside plant  550  based on a position of optical switch  580 , as ingress optical data signal  582 . That is ingress optical data signal  582  may be similar to egress optical data signal  539 . Ingress optical data signal  582  may be received by WDM  513  via port  584 . WDM  513  may demultiplex ingress optical data signal  582  into a multi-wavelength downstream optical data signal  599 , an XGPON/10GEPON optical data signal that may be output on port  595  onto a first fiber (e.g., XGPON/10GEPON  554 ), and/or a GPON optical data signal output on port  596  onto a second fiber (e.g., GPON  552 ). The XGPON/10GEPON optical data signal may be received on XGPON/10GEPON port  553  and the GPON optical data signal may be received on GPON port  551 . 
     The multi-wavelength downstream optical data signal  599  may be output on port  597  and received by EDFA  544 . The multi-wavelength downstream optical data signal  559  may comprise 10 GbE optical data signals. A gain associated EDFA  544  may be based at least in part on a distance that 10 GbE optical data signals have to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, the gain of booster optical amplifier  544  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of booster optical amplifier  544  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  540  and/or the length of secondary fiber  511 ). Multi-wavelength upstream optical data signal  599  may be amplified by EDFA  544 , and EDFA  544  may output multi-wavelength downstream optical data signal  598  to DWDM  515 . 
     DWDM  515  may demultiplex the multi-wavelength downstream optical data signal  598  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength downstream optical data signal  598  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  515  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  512 . Each of the transponders of 20×10 GbE DS  512  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE DS  512  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. In some embodiments, DWDM  515  may output one or more 10 GbE optical data signals (e.g., RPD DS  527 ) to a remote physical (PHY) device (RPD) (e.g., RPD  517 ). RPD  517  may be similar to Remote PHY Node  207  in functionality. RPD  517  may convert the one or more 10 GbE optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. RPD  517  may also convert one or more electrical signals into one or more 10 GbE optical data signal for transmission to a transponder (e.g., 20×10 GbE UP  514 ). 
     The operation of outside plant  550  may be further described by way of the processing of an upstream optical data signal transmitted to headend  530 . Each of the transponders of 20×10 GbE UP  514  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  514  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  514  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  519  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength upstream optical data signal (e.g., multi-wavelength downstream optical data signal  569 ) to port  593  of WDM  513 . In some embodiments, RPD  517  may transmit one or more 10 GbE optical data signals (e.g., RPD UP  537 ) to one or more of 20×10 GbE UP  514 . RPD UP  537  may be 10 GbE optical data signals generated by RPD  517  in response to RPD  517  receiving electrical signals on coaxial cables connecting a remote physical (PHY) network (e.g., remote PHY network  216 ) to DWDM  519 . The multi-wavelength upstream optical data signal  569  may be a 10 GbE optical data signal. More specifically, DWDM  519  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength upstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     WDM  513  may be a five port wave division multiplexer (WDM), or a five port circulator, that receives a multi-wavelength upstream optical data signal on port  593 . WDM  513  may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  554 ), on port  595 , a GPON signal, carried on a second fiber (e.g., GPON  552 ), on port  596 , and may multiplex the multi-wavelength upstream optical data signal with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  554  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm range. GPON  552  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm. WDM  513  outputs an egress optical data signal from port  584 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  513  may multiplex the multi-wavelength upstream optical data signal, the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  507 ,  515 , and  519  multiplex optical data signals. The egress optical data signal (e.g., egress optical data signal  583 ) may be output on port  584  of WDM  513  and optical switch  580  may switch egress optical data signal  583  onto primary fiber  540  or secondary fiber  511  depending on the position of switch  580 . Egress optical data signal  583  may be transmitted on primary fiber  540  to a first connector at headend  530 , or may be transmitted on secondary fiber  511  to a second connector at headend  530 . 
     The operation of headend  530  may be further described by way of the processing of an upstream optical data signal received from outside plant  550 . Egress optical data signal  583  may be received on the first or second connector at headend  530  based on a position of optical switch  508 , as ingress optical data signal  543 . That is ingress optical data signal  543  may be similar to egress optical data signal  583 . Ingress optical data signal  543  may be received by WDM  509  via port  542 . 
     WDM  509  may demultiplex ingress optical data signal  543  into a multi-wavelength upstream optical data signal  559 , an XGPON/10GEPON optical data signal that may be output on port  548  onto a first fiber (e.g., XGPON/10GEPON  534 ), and/or a GPON optical data signal output on port  549  onto a second fiber (e.g., GPON  532 ). The XGPON/10GEPON optical data signal may be received on XGPON/10GEPON port  503  and the GPON optical data signal may be received on GPON port  501 . 
     The multi-wavelength upstream optical data signal  559  may be output on port  545  and received by EDFA  541 . The multi-wavelength upstream optical data signal  559  may comprise 10 GbE optical data signals. A gain associated EDFA  541  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of EDFA  544 . Multi-wavelength upstream optical data signal  559  may be amplified by EDFA  541 , and EDFA  541  may output multi-wavelength upstream optical data signal  529  to WDM  505 . WDM  505  may receive the multi-wavelength upstream optical data signal  529  on port  543  of WDM  505 . WDM  505  may output multi-wavelength upstream optical data signal  536  which is substantially the same as multi-wavelength upstream optical data signal  529 . WDM  505  may function as a circulator when receiving multi-wavelength upstream optical data signal  529  on port  543  and outputting multi-wavelength upstream optical data signal  536  on port  542 . Multi-wavelength upstream optical data signal  536  may be received by DWDM  507 . 
     The multi-wavelength upstream optical data signal  536  may comprise 10 GbE optical data signals. DWDM  507  may demultiplex the multi-wavelength upstream optical data signal  536  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength upstream optical data signal  536  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  507  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  506 . Each of the transponders of 20×10 GbE UP  506  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  506  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  6    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure.  FIG.  6    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  6   , headend  630  is a smart integrated OCML headend, which is a circuit, comprising a AWG (e.g., AWG  607 ), a first WDM (e.g., WDM  605 ), a second WDM (e.g., WDM  609 ), a GPON port (e.g., GPON PORT  601 ), an XGPON/10GEPON port (e.g., XGPON/10GEPON PORT  603 ), a first EDFA (e.g., EDFA  641 ), a second EDFA (e.g., EDFA  643 ), and an optical switch  613  to feed a primary optical fiber (e.g., Primary Fiber  617 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  627 ). AWG  607  may be similar in functionality to DWDM  106  and WDM  605  and WDM  609  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE and GPON/XGPON/10GEPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and an outside plant (e.g., Outside plant  650 ) or field hub. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     In one aspect, headend  630  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  604 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  606 ). 20×10 GbE DS  604  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  606  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  604  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  606  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  630  may be described by way of the processing of downstream optical data signals transmitted from headend  630  to an outside plant (e.g., Outside plant  650 ) or field hub, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  604  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  604  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  604  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     AWG  607  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g.,  638 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal  638  may be a 10 GbE optical data signal. More specifically, AWG  607  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal  638 , may be input to WDM  605 . WDM  605  may be a five port wave division multiplexer (WDM), or a five port circulator, that receives multi-wavelength downstream optical data signal  638  on port  602 . WDM  605  may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  634 ), on port  610 , a GPON signal, carried on a second fiber (e.g., GPON  632 ), on port  667 , and may multiplex multi-wavelength downstream optical data signal  638  with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  634  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm range. GPON  632  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm or 1310 nm. WDM  605  outputs an egress optical data signal from port  615 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  605  may multiplex multi-wavelength downstream optical data signal  638 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way AWG  607  multiplexes optical data signals. 
     WDM  605  may output multi-wavelength downstream optical data signal  639  to an EDFA (e.g., EDFA  641 ). A gain of the EDFA may be based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, the EDFA may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain EDFA  641  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  617  and/or the length of secondary fiber  627 ). Multi-wavelength downstream optical data signal  639  may be amplified by EDFA  641 , and EDFA  641  may output multi-wavelength downstream optical data signal  640  to port  615  of WDM  609 . WDM  609  outputs an egress optical data signal from port  616 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. 
     Egress optical data signal  620  by WDM  609  and optical switch  613  may switch egress optical data signal  620  onto primary fiber  617  or secondary fiber  627  depending on the position of switch  613 . Egress optical data signal  620  may be transmitted on primary fiber  617  to port  621  at passive optical component  625 , or may be transmitted on secondary fiber  627  to port  631  at passive optical component  625 . Passive optical component  625  may output ingress optical data signal  656  from port  629  to port  697  at WDM  673 . 
     Ingress optical data signal  656  may be received by WDM  673  via port  697 . WDM  673  may demultiplex ingress optical data signal  656  into a multi-wavelength downstream optical data signal  659 , an XGPON/10GEPON optical data signal that may be output on port  699  onto a first fiber (e.g., XGPON/10GEPON  654 ), and/or a GPON optical data signal output on port  698  onto a second fiber (e.g., GPON  652 ). The XGPON/10GEPON optical data signal may be received on XGPON/10GEPON port  653  and the GPON optical data signal may be received on GPON port  651 . 
     The multi-wavelength downstream optical data signal  659  may be output on port  696  and received by array waveguide gratings (AWG) AWG  675 . The multi-wavelength downstream optical data signal  659  may comprise 10 GbE optical data signals. AWG  675  may demultiplex the multi-wavelength upstream optical data signal  659  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength downstream optical data signal  659  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. AWG  675  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  612 . Each of the transponders of 20×10 GbE DS  612  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE DS  612  may transmit the twenty SONET/SDH optical data signals to a RPD (e.g., RPD  677 ) on the SONET/SDH optical network connection. In some embodiments, AWG  675  may output one or more 10 GbE optical data signals (e.g., RPD DS  627 ) RPD  677 . RPD  677  may be similar to Remote PHY Node  207  in functionality. RPD  677  may convert the one or more 10 GbE optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. RPD  617  may also convert one or more electrical signals into one or more 10 GbE optical data signal for transmission to a transponder (e.g., 20×10 GbE UP  614 ). 
     The operation of outside plant  650  may be further described by way of the processing of an upstream optical data signal transmitted to headend  630 . Each of the transponders of 20×10 GbE UP  614  may receive a SONET/SDH optical data signal from RPD  677  and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  614  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  614  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     AWG  675  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength upstream optical data signal (e.g., multi-wavelength upstream optical data signal  658 ) comprising the twenty corresponding second optical data signals onto a fiber. In some embodiments, RPD  677  may transmit one or more 10 GbE optical data signals (e.g., RPD UP  637 ) to one or more of 20×10 GbE UP  614 . RPD UP  637  may be 10 GbE optical data signals generated by RPD  677  in response to RPD  677  receiving electrical signals on coaxial cables connecting a remote physical (PHY) network (e.g., remote PHY network  216 ) to AWG  675 . The multi-wavelength upstream optical data signal  658  may be a 10 GbE optical data signal. More specifically, AWG  675  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength upstream optical data signal  658 , may be input to WDM  673 . WDM  673  may be a four port wave division multiplexer (WDM), or a four port circulator, that receives multi-wavelength upstream optical data signal  658  on port  696 . WDM  673  may also receive an XGPON/10GEPON signal, carried on a first fiber (e.g., XGPON/10GEPON  654 ), on port  699 , a GPON signal, carried on a second fiber (e.g., GPON  652 ), on port  698 , and may multiplex multi-wavelength upstream optical data signal  658  with the XGPON/10GEPON and GPON signal. XGPON/10GEPON  654  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm range. GPON  652  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm or 1310 nm. WDM  673  outputs an egress optical data signal from port  697 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and/or GPON optical data signals. WDM  673  may multiplex multi-wavelength upstream optical data signal  658 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way AWG  675  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  657 ) may be output on port  697  of WDM  673  to port  629  of passive optical component  625 . Passive optical component  625  may switch egress optical data signal  657  onto primary fiber  617  or secondary fiber  627  depending on a position of a switch in passive optical component  625 . Egress optical data signal  657  may be transmitted on primary fiber  617  to a first port (e.g., port  615 ) at headend  630 , or may be transmitted on secondary fiber  627  to a second port (e.g., port  623 ) at headend  630 . 
     The operation of headend  630  may be further described by way of the processing of an upstream optical data signal received from outside plant  650 . Egress optical data signal  657  may be received on the first or second connector at headend  630  based on a position of optical switch  613 , as ingress optical data signal  611 . That is ingress optical data signal  611  may be similar to egress optical data signal  657 . Ingress optical data signal  611  may be received by WDM  609  via port  616 . 
     WDM  609  may demultiplex ingress optical data signal  611  into a multi-wavelength upstream optical data signal  619 . The multi-wavelength upstream optical data signal  619  may be output on port  618  and received by EDFA  643 . The multi-wavelength upstream optical data signal  619  may comprise 10 GbE optical data signals. A gain associated EDFA  643  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of EDFA  641 . Multi-wavelength upstream optical data signal  619  may be amplified by EDFA  643 , and EDFA  643  may output multi-wavelength upstream optical data signal  633  to WDM  605 . WDM  605  may receive the multi-wavelength upstream optical data signal  633  on port  608  of WDM  605 . WDM  605  may output multi-wavelength upstream optical data signal  636  which is substantially the same as multi-wavelength upstream optical data signal  633 . WDM  605  may function as a circulator when receiving multi-wavelength upstream optical data signal  633  on port  608  and outputting multi-wavelength upstream optical data signal  636  on port  602 . Multi-wavelength upstream optical data signal  636  may be received by AWG  607 . 
     The multi-wavelength upstream optical data signal  636  may comprise 10 GbE optical data signals. AWG  607  may demultiplex the multi-wavelength upstream optical data signal  636  into individual optical data signals in accordance with the individual wavelengths of the 10 GbE optical data signals. More specifically, the multi-wavelength upstream optical data signal  636  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. AWG  607  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  606 . Each of the transponders of 20×10 GbE UP  606  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  606  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  7    depicts different passive optical network (PON) transceiver parameters associated with downstream transmitting circuits and upstream transmitting circuits, in accordance with the disclosure. Parameters  700 , comprise a wavelength column (i.e., wavelength  701 ), a transmission (Tx) power column (i.e., Tx power  702 ), a dispersion penalty column (i.e., dispersion penalty  703 ), a loss budget column (i.e., loss budget  705 ), and a minimum receive power column (i.e., minimum receive power  709 ) for different passive optical network (PON) transceivers (i.e., GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731 ). 
     Wavelength  701  may include the wavelength of a downstream optical data signal (i.e., downstream  712 , downstream  722 , and downstream  732 ) transmitted by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend to a corresponding PON transceiver at an outside plant. Wavelength  701  may include the wavelength of an upstream optical data signal (i.e., upstream  713 , upstream  723 , and upstream  733 ) received by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend from a corresponding PON transceiver at an outside plant. The downstream optical data signal may be an optical data signal sent from an OCML headend to an outside plant, as disclosed herein. The upstream optical data signal may be an optical data signal received at the OCML headend from an outside plant, as disclosed herein. 
     Tx power  702  may include the transmission power of the downstream optical data signal (i.e., downstream  712 , downstream  722 , and downstream  732 ) from each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend to a corresponding PON transceiver at an outside plant. Tx power  702  may include the transmission power of the upstream optical data signal (i.e., upstream  713 , downstream  723 , and downstream  733 ) transmitted by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an outside plant to a corresponding PON transceiver at an OCML headend. 
     Dispersion penalty  703  may include a power dispersion penalty associated with the downstream optical data signal (i.e., downstream  712 , downstream  722 , and downstream  732 ) being transmitted by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  on a fiber from an OCML headend to a corresponding PON transceiver at an outside plant. Dispersion penalty  703  may include a power dispersion penalty associated with the upstream optical data signal (i.e., upstream  713 , upstream  723 , and upstream  733 ) being received by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend from a corresponding PON transceiver at an outside plant. 
     In some embodiments, an optical data signal may experience dispersion as it travels through an optical fiber. The dispersion penalty may be based at least in part on a bandwidth of the optical fiber, a dispersion constant for a given wavelength carrying the optical data signal, the length of the optical fiber, and a wavelength spread of a laser generating the optical data signal. More specifically the dispersion penalty may be determined by the expression PP D (B, D, L, σ λ )=5*log[1+2*π*(B*D*L*σ λ ) 2 ]. B is the bandwidth of the optical fiber carrying the optical data signal, D is the dispersion constant, L is the length of the optical fiber, and σ λ  is the wavelength spread of the laser. B and L may be constants that are determined during a design of fiber to the home (FTTH) network like the one depicted in  FIG.  2   . D may be based at least in part a zero dispersion wavelength for the optical data signal, a dispersion wavelength of the optical data signal, and a slope of the dispersion characteristic for the zero dispersion wavelength of the optical data signal. Specifically, D may be equal to 
                   S   0     4     *     (     λ   -       λ   0   4       λ   3         )       ,         
wherein S 0  is the slope of the dispersion characteristic for the zero dispersion wavelength (λ 0 ) of the optical data signal. The zero dispersion wavelength may be the wavelength at which material dispersion and waveguide dispersion cancel one another out. λ may be the dispersion wavelength of the optical data signal. The units of S 0  may be picoseconds per the product of nanometers squared and kilometer
 
     
       
         
           
             
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             . 
           
         
       
     
     Loss budget  705  may include a loss budget associated with the downstream optical data signal (i.e., downstream  712 , downstream  722 , and downstream  732 ) being transmitted by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend to a corresponding PON transceiver at a outside plant along a fiber connecting the OCML headend and outside plant. Loss budget  705  may include a loss budget associated with the upstream optical data signal (i.e., upstream  713 , upstream  723 , and upstream  733 ) being received by each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  at an OCML headend from a corresponding PON transceiver at an outside plant along a fiber connecting the OCML headend and outside plant. 
     Minimum receive power  709  may include a minimum receive power necessary for each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731 , at an outside plant, to correctly decode one or more bits received from a corresponding PON transceiver at an OCML headend in a downstream optical data signal (i.e., downstream  712 , downstream  722 , and downstream  732 ). For instance, a minimum receive power level may be necessary for each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  to correctly detect a bit value of “1”, at the outside plant, when a bit value of “1” is transmitted by a corresponding PON transceiver at an OCML headend. Minimum receive power  709  may include a minimum receive power necessary for each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/ 10 GEPON N 1   731 , at an OCML headend, to correctly decode one or more bits received from a corresponding transceiver at a outside plant in an upstream optical data signal. For instance, a minimum receive power level may be necessary for each of PON transceivers GPON C+  711 , XGPON/10GEPON N 2   a    721 , or XGPON/10GEPON N 1   731  to correctly detect a bit value of “1”, at the OCML headend, when a bit value of “1” is transmitted by a corresponding PON transceiver at the outside plant. 
     In some embodiments, a GPON C+ transceiver (i.e., GPON C+  711 ), at an OCML headend, may transmit a downstream (i.e., downstream  712 ) optical data signal with a wavelength (i.e., wavelength  701 ) of 1490 nanometers, a Tx power (i.e., Tx power  702 ) between 3 and 7 decibel-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 1 decibel, a loss budget (i.e., loss budget  705 ) of 32 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −30 decibels to a GPON C+ transceiver at an outside plant. 
     In some embodiments, a GPON C+ transceiver (i.e., GPON C+  711 ), at an outside plant, may transmit an upstream (i.e., upstream  713 ) optical data signal, with a wavelength (i.e., wavelength  701 ) of 1310 nanometers, a Tx power (i.e., Tx power  702 ) between 0.5 and 5 decible-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 0.5 decibel, a loss budget (i.e., loss budget  705 ) of 32 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −32 decibels to a GPON C+ transceiver at an OCML headend. 
     In some embodiments, an XGPON/10GEPON N 2   a  transceiver (i.e., XGPON/10GEPON N 2   a    721 ), at an OCML headend, may transmit a downstream (i.e., downstream  722 ) optical data signal with a wavelength (i.e., wavelength  701 ) of 1575 nanometers, a Tx power (i.e., Tx power  702 ) between 4 and 8 decibel-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 1 decibel, a loss budget (i.e., loss budget  705 ) of 31 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −28 decibels to an XGPON/10GEPON N 2   a  transceiver at an outside plant. 
     In the same, or a similar embodiment, an XGPON/10GEPON N 2   a  transceiver (i.e., XGPON/10GEPON N 2   a    721 ), at an outside plant, may transmit an upstream (i.e., upstream  723 ) optical data signal, with a wavelength (i.e., wavelength  701 ) of 1270 nanometers, a Tx power (i.e., Tx power  702 ) between 2 and 7 decible-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 0.5 decibel, a loss budget (i.e., loss budget  705 ) of 31 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −29.5 decibels to an XGPON/10GEPON N 2   a  transceiver at an OCML headend. 
     In some embodiments, an XGPON/10GEPON N 1  transceiver (i.e., XGPON/10GEPON N 1   731 ), at an OCML headend, may transmit a downstream (i.e., downstream  732 ) optical data signal with a wavelength (i.e., wavelength  701 ) of 1575 nanometers, a Tx power (i.e., Tx power  702 ) between 2 and 6 decibel-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 1 decibel, a loss budget (i.e., loss budget  705 ) of 29 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −28 decibels to an XGPON/10GEPON N 1  transceiver at an outside plant. 
     In the same, or a similar embodiment, an XGPON/10GEPON N 1  transceiver (i.e., XGPON/10GEPON N 1   731 ), at an outside plant, may transmit an upstream (i.e., upstream  733 ) optical data signal, with a wavelength (i.e., wavelength  701 ) of 1270 nanometers, a Tx power (i.e., Tx power  702 ) between 2 and 7 decible-milliwatts, a dispersion penalty (i.e., dispersion penalty  703 ) of 0.5 decibel, a loss budget (i.e., loss budget  705 ) of 29 decibels, and a minimum receive power (i.e., minimum receive power  709 ) of −27.5 decibels to an XGPON/10GEPON N 1  transceiver at an OCML headend. 
       FIG.  8    depicts a graphical representation of wavelengths used to transport one or more signals, in accordance with the disclosure. OCML optical wavelengths  801  illustrate the different wavelengths of the optical data signals described herein. For GPON optical data signals disclosed herein, a wavelength of 1310 nm may be used to transmit an upstream GPON optical data signal from an outside plant to an OCML headend. For GPON optical data signals disclosed herein, a wavelength of 1490 nm may be used to transmit a downstream GPON optical data signal from the OCML headend to the outside plant. For 10 GbE optical data signals disclosed herein, a wavelength between 1530 and 1565 nm may be used to transmit an upstream 10 GbE optical data signal to the OCML headend from the outside plant, and to transmit a downstream 10 GbE optical data signal to the outside plant from the OCML headend. In some embodiments, the upstream XGPON/10GEPON optical data signals disclosed herein may have wavelengths between 1260 nm and 1280 nm (e.g., XGPON/10GEPON  802 ). In some embodiments, the downstream XGPON/10GEPON optical data signals disclosed herein may have wavelengths between 1571 nm and 1591 nm. 
       FIG.  9    depicts a stimulated Raman scattering (SRS) diagram, in accordance with the disclosure. Raman gain spectrum  900  may be Raman gain coefficients for an optical fiber comprised of silica and Germania-oxide (GeO 2 ). Raman gain spectrum  900  may be a plot of Raman gain coefficients against different wavelengths (i.e., wavelength  903 ). SRS is a nonlinear process where higher frequency optical channels are depleted and lower frequency optical channels are amplified. With each optical channel being modulated, the intensity of higher frequency optical data signals modulate the intensity of lower frequency optical data signals. As a result, SRS may lead to optical crosstalk between channels. The optical crosstalk due to SRS may be referred to as SRS optical crosstalk, and may be defined by the following expression. 
                 XT     SRS   ,   i       =       P   2     ⁢       ∑     k   ≠   i             g   2       A   eff   2       ⁢   i           ,       k   ⁡   (         (     1   -     e     a   ⁢   L         )     2     +     4   ⁢     e       -   a     ⁢   L       ⁢       sin   2     (       Ω   ⁢     d     i   ,   k       ⁢   L     2     )         )     /     (       a   2     +       Ω   2     ⁢     d     i   ,   k     2         )             
That is the optical crosstalk experienced on a channel “i” (XT SRS,i ) is based at least in part on the square of the optical fiber launch power per channel (P) at which an optical data signal is transmitted. The optical crosstalk may also be based at least in part on Raman gain coefficients (g i,k   2 ) between channel “i” and a channel “k”. The Raman gain coefficients may be based at least in part on a Raman gain slope and the frequency at which optical data signals on channel “i” are propagating and the frequency at which optical data signals on channel “k” are propagating. The optical crosstalk may also be based at least in part on a fiber loss (α) and length (L) of the optical fiber. The optical crosstalk may also be based at least in part on a subcarrier modulation frequency (Ω) and a group velocity mismatch between optical data signals propagating on channel “i” and optical data signals propagating on channel “k” (d i,k ).
 
     Depending on the wavelength separation between the optical data signals propagating on channel “i” and the optical data signals propagating on channel “k”, polarization states of the optical data signals in channels “i” and “k”, the optical fiber launch powers for channels “i” and “k” SRS optical crosstalk may occur which depletes shorter (pump depletion  902 ) wavelengths (e.g., GPON 1490 nm) and amplifies the higher (stokes) wavelengths resulting in signal degradation for certain optical data signals (e.g., 10 GbE optical data signal degradation 901). In some embodiments, the effect is on lower RF frequencies carried on longer wavelength optical data signals. Because of this interference from a GPON optical data signal with a wavelength of 1490 nm may cause interference or signal degradation of a 10 GbE optical data signal with a wavelength of 1560 nm. In some embodiments, the SRS optical crosstalk may be 35 dB which may result in a tolerable BER. 
       FIG.  10    depicts a schematic illustration of wavelength and optical fiber monitoring of cascaded OCML headends in accordance with the disclosure. Headend  1001  is a smart integrated OCML headend, which is a circuit, comprising one or more EDFAs (e.g., Booster Optical amplifiers  1012  and  1019 ), a DWDM (e.g., DWDM  1007 ), one or more WDMs (e.g., WDM  1008  and  1023 ), one or more DCMs (e.g., DCM  1018  and  1015 ), and an optical switch  1027  to feed a primary optical fiber (e.g., Primary Fiber  1031 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1032 ). The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to an outside plant or field hub housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     In one aspect, headend  1001  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1003 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1004 ). 20×10 GbE DS  1003  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1004  may receive upstream data over 10 GbE wavelengths. Headend  1001  may comprise two PON  1002  connectors, one of which may be a GPON connector (e.g., GPON  1006 ) and one of which may be an XGPON/10GEPON connector (e.g., XGPON/10GEPON  1005 ). Headend  1001  may also comprise two wavelength-monitoring ports (e.g., wavelength-monitoring ports  1039 ), a primary optical fiber (e.g., primary optical fiber  1031 ) and a secondary optical fiber (e.g., secondary optical fiber  1032 ) that transmit and receive a plurality of multi-wavelength 10 GbE and GPON/XGPON/10GEPON optical signals. Primary optical fiber  1031  and secondary optical fiber  1032  may transmit a first plurality of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON optical signals from headend  1001  to an outside plant (not illustrated in  FIG.  10   ), and may receive a second plurality of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON optical signals from the outside plant. 
     The operation of headend  1001  may be described by way of the processing of downstream optical data signals transmitted from headend  1001  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1003  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1003  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1003  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1007  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1098 ) comprising the twenty corresponding second optical data signals onto a fiber. More specifically, DWDM  1007  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength downstream optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1098 , may be input to a WDM (e.g. WDM  1008 ). WDM  1008  may be a three port wave division multiplexer (WDM), or a three port circulator, that receives 10 GbE DS  1098  on port  1010  and outputs 10 GbE DS  1098  on port  1009  as 10 GbE DS  1013 . 10 GbE DS  1013  may be substantially the same as 10 GbE DS  1098  because WDM  1008  may function as a circulator when 10 GbE DS  1098  is input on port  1010 . 
     WDM 10 GbE DS  1013  may be input to an EDFA (e.g., booster optical amplifier  1012 ). A gain of the booster optical amplifier (e.g., booster optical amplifier  1012 ) may be based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, the gain of booster optical amplifier  1012  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of booster optical amplifier  1012  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1031  and/or the length of secondary fiber  1032 ). 10 GbE DS  1013  may be amplified by booster optical amplifier  1012 , and booster optical amplifier  1012  may output 10 GbE DS  1017  to DCM  1018 . 
     10 GbE DS  1017  may be input into a DCM (e.g., DCM  1018 ) to compensate for dispersion that 10 GbE DS  1017  may experience after being amplified by an EDFA and multiplexed by a WDM, with other optical data signals, that are downstream from the DCM. The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  1001  over a fiber connecting headend  1001  to a field hub or outside plant. In some embodiments, DCM  1018  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  1018  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  1018  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. 
     WDM  1023  may be a WDM that may multiplex 10 GbE DS  1022  with one or more PON signals carried on XGPON/10GEPON  1005  and GPON  1006 . 10 GbE DS  1022  may be a multi-wavelength optical data signal, wherein the wavelengths comprise the same wavelengths as 10 GbE DS  1022 . In some embodiments, the wavelengths of the multi-wavelength optical data signal 10 GbE DS  1022  may be within the conventional c band of wavelengths, which may include wavelengths within the 1520 nm-1565 nm range. XGPON/10GEPON  1005  may be a fiber carrying an XGPON/10GEPON optical data signal with a wavelength within the 1571 nm-1591 nm or 1260 nm-1280 nm range. GPON  1006  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm or 1310 nm. The XGPON/10GEPON optical signal may be input to WDM  1023  on port  1021  and the GPON optical signal may be input to WDM  1023  on port  1024 . WDM  1023  outputs an egress optical data signal from port  1025 , which may be a multi-wavelength optical data signal comprising 10 GbE, XGPON/10GEPON, and GPON optical data signals. WDM  1023  may multiplex 10 GbE DS  1022 , the XGPON/10GEPON optical data signal, and GPON optical data signal the same way DWDM  1007  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  1020 ) may be output on port  1025  of WDM  1023  and optical switch  1027  may switch egress optical data signal  1020  out of connector  1029  or connector  1034 . In some embodiments, connector  1029  may be a primary connector and connector  1034  may be a secondary connector or a backup connector. Wavelength monitoring connector  1039  may connect connector  1028  to a first port of wavelength-monitoring ports  1039 , and wavelength monitoring connector  1034  may connect connector  1035  to a second port of wavelength-monitoring ports  1039 . Wavelength-monitoring ports  1039  may monitor the wavelengths in egress optical data signal  1020  via connector  1029  or connector  1034  depending on the position of switch  1027 . Egress optical data signal  1020  may exit headend  1001  either via connector  1030  connected to primary fiber  1031  or via connector  1033  connected to secondary fiber  1032  depending on the position of switch  1027 . Egress optical data signal  1020  may be transmitted on primary fiber  1031  to a first connector in the field hub or outside plant, or may be transmitted on secondary fiber  1032  to a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     The operation of headend  1001  may be described by way of the processing of upstream optical data signals received at headend  1001  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, XGPON/10GEPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  1031  or secondary fiber  1032  depending on the position of switch  1027 . Because the multi-wavelength ingress optical data signal is routed to port  1025  of WDM  1023 , and is altered negligibly between connector  1028  and port  1025  or connector  1035  and port  1025 , depending on the position of switch  1027 , the multi-wavelength ingress optical data signal may be substantially the same as ingress optical data signal  1026 . The multi-wavelength ingress optical data signal may traverse connector  1028  and switch  1027 , before entering WDM  1023  via port  1025  if switch  1027  is connected to connector  1028 . The multi-wavelength ingress optical data signal may traverse connector  1035  and switch  1027 , before entering WDM  1023  via port  1025  if switch  1027  is connected to connector  1035 . WDM  1023  may demultiplex one or more 10 GbE optical data signals, XGPON/10GEPON optical data signals, and/or GPON optical data signals from ingress optical data signal  1026 . WDM  1023  may transmit the one or more XGPON/10GEPON optical data signals along XGPON/10GEPON  1005  to one of PON connectors  1002  via port  1024 . WDM  1023  may transmit the one or more GPON optical data signals along GPON  1006  to one of PON connectors  1002  via port  1021 . WDM  1023  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1038 ) out of port  1037  to BOA  1019 . 
     A gain of BOA  1019  may be based at least in part on a distance that the SONET/SDH egress optical data signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment on the SONET/SDH optical network connection. For instance, the gain of BOA  1019  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of BOA  1019  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of the fiber of the SONET/SDH optical network connection). 10 GbE UP  1038  may be amplified by BOA  1019 , and BOA  1019  may output 10 GbE UP  1014  to DCM  1015 . 
     The wavelength of 10 GbE UP  1014  may be within the conventional c band of wavelengths, which may include wavelengths within the 1520 nm-1565 nm range. The one or more XGPON/10GEPON optical data signals may have a wavelength within the 1571 nm-1591 nm or 1260 nm-1280 nm range, and the one or more GPON optical data signals may have a wavelength of 1490 nm. 
     In some embodiments, DCM  1015  may be configured to balance positive and/or negative dispersion that may be introduced to a SONET/SDH egress optical data signal that may enter headend  1001  from 20×10 GbE UP  1004 . The SONET/SDH egress optical data signal may be an upstream signal from a field hub or outside plant destined for a MTC. For example, a customer premise may be connected to the field hub or outside plant and may send one or more packets via a SONET/SDH network to the field hub or outside plant which may in turn transmit the one or more packets using 10 GbE optical data signals to headend  1001 . The one or more packets may be destined for a company web server connected to the MTC via a backbone network. Because headend  1001  may be collocated in a STC that is connected to the MTC via an optical ring network, wherein the connection between the STC and MTC is an SONET/SDH optical network connection, DCM  1015  may be configured to compensate for positive and/or negative dispersion on the SONET/SDH optical network connection. That is DCM  1015  may be configured to reduce temporal broadening of the SONET/SDH egress optical data signal or temporal contraction of the SONET/SDH egress optical data signal. DCM  1015  may input 10 GbE UP  1016  and my output 10 GbE UP  1014  to WDM  1008 . 
     WDM  1008  may receive 10 GbE UP  1014  on port  1011 , and may output 10 GbE UP  1009  on port  1010  as a multi-wavelength upstream optical data signal (e.g., 10 GbE UP  1009 ). 10 GbE UP  1009  is substantially the same as 10 GbE UP  1014  because WDM  1008  may function as a circulator when 10 GbE UP  1014  is input to port  1011 . 10 GbE UP  1009  may be received by DWDM  1007 , and DWDM may demultiplex one or more 10 GbE optical data signals from 10 GbE UP  1009 . Because 10 GbE UP  1009  is a dispersion compensated amplified version of the multi-wavelength ingress optical data signal, DWDM  1007  may demultiplex the one or more optical data signals into individual optical data signals in accordance with the individual wavelengths of any 10 GbE optical data signals in the multi-wavelength ingress optical data signal. More specifically, 10 GbE UP  1009  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1007  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1004 . Each of the transponders of 20×10 GbE UP  1004  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1014  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
     Headend  1086  and the components therein may be similar in function to the components in headend  1001 . Optical line monitor  1011  ports c and g may be connected to wavelength-monitoring ports  1039  and optical line monitor  1011  ports b and f may be connected to wavelength-monitoring ports  1084 . 
       FIG.  11    a schematic illustration of wavelength and optical fiber monitoring of an OCML headend in accordance with the disclosure. Headend  1102  and the components therein may be similar in function to the components in headend  1001 . Optical line monitor  1011  ports a and e may be connected to wavelength-monitoring ports  1178 . 
       FIG.  12    depicts an access network diagram of an OCML headend comprising wavelength division multiplexers (WDMs), a dense wavelength division multiplexer (DWDM), and optical amplifiers, in accordance with the disclosure.  FIG.  12    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  12   , headend  1201  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  1205 ), a first WDM (e.g., WDM  1210 ), a second WDM (e.g., WDM  1220 ), a GPON/EPON connector (e.g., GPON/EPON  1218 ), a booster amplifier BOA (e.g., BOA  1215 ), an optical pre-amplifier (OPA) (e.g., OPA  1214 ), an optical switch  1226  to feed a primary optical fiber (e.g., Primary Fiber  1235 ) via a primary variable optical attenuator (VOA) (e.g., VOA  1231 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1236 ) via a secondary variable optical attenuator (VOA) (e.g., VOA  1232 ). DWDM  1205  may be similar in functionality to DWDM  106  and WDM  1210  and WDM  1220  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE and GPON/EPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     The EPON signals may operate with the same optical frequencies as GPON and time division multiple access (TDMA). The raw line data rate is 1.25 Gbits/s in both the downstream and upstream directions. 
     EPON is fully compatible with other Ethernet standards, so no conversion or encapsulation is necessary when connecting to Ethernet-based networks on either end. The same Ethernet frame is used with a payload of up to 1518 bytes. EPON may not use a carrier sense multiple access (CSMA)/collision detection (CD) access method used in other versions of Ethernet. 
     There is a 10-Gbit/s Ethernet version designated as 802.3ay. The line rate may be 10.3125 Gbits/s. The primary mode is 10 Gbits/s upstream as well as downstream. A variation uses 10 Gbits/s downstream and 1 Gbit/s upstream. The 10-Gbit/s versions use different optical wavelengths on the fiber, 1571 to 1591 nm downstream and 1260 to 1280 nm upstream so the 10-Gbit/s system can be wavelength multiplexed on the same fiber as a standard 1-Gbit/s system. 
     In one aspect, headend  1201  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1203 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1204 ). 20×10 GbE DS  1203  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1204  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  1203  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  1204  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  1201  may be described by way of the processing of downstream optical data signals transmitted from headend  1201  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1203  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1203  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1203  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1205  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1206 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal 10 GbE DS  1206  may be a 10 GbE optical data signal. More specifically, DWDM  1205  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1206 , may be input to WDM  1210 . WDM  1210  may be a three port circulator, that receives multi-wavelength downstream optical data signal 10 GbE DS  1206  on port  1208 , and outputs multi-wavelength downstream optical data signal 10 GbE DS  1206 , on port  1211  as multi-wavelength downstream optical data signal 10 GbE DS  1213  to BOA  1215 . 
     BOA  1215  may have a gain that is based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, BOA  1215  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain BOA  1215  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1235  and/or the length of secondary fiber  1236 ). Multi-wavelength downstream optical data signal 10 GbE DS  1213  may be amplified by BOA  1215 , and BOA  1215  may output multi-wavelength downstream optical data signal 10 GbE DS  1216  to port  1217  of WDM  1220 . WDM  1220  outputs an egress optical data signal from port  1219 , which may be a multi-wavelength optical data signal comprising 10 GbE, EPON, and/or GPON optical data signals. The EPON and/or GPON optical data signals may be received on a GPON/EPON connector (e.g., GPON/EPON  1218 ) from PON port  1202 . 
     Egress optical data signal  1225  may be output by WDM  1220  and optical switch  1226  may switch egress optical data signal  1225  onto connector  1228  or connector  1227  depending on the position of switch  1226 . In some embodiments, connector  1228  may be a primary connector and connector  1227  may be a secondary connector or a backup connector. Wavelength monitoring connector  1230  may connect connector  1228  to a first port of wavelength-monitoring ports  1237 , and wavelength monitoring connector  1229  may connect connector  1227  to a second port of wavelength-monitoring ports  1237 . Wavelength-monitoring ports  1237  may monitor the wavelengths in egress optical data signal  1225  via connector  1228  or connector  1227  depending on the position of switch  1226 . Egress optical data signal  1225  may exit headend  1201  either via connector  1228  connected to primary fiber  1235 , as egress optical data signal  1240 , or via connector  1227  connected to secondary fiber  1236 , as egress optical data signal  1241 , depending on the position of switch  1226 . Egress optical data signal  1225  may be transmitted as, egress optical data signal  1240 , on primary fiber  1235  to a first connector in the field hub or outside plant. Egress optical data signal may be transmitted as, egress optical data signal  1241 , on secondary fiber  1236  to a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     Variable optical attenuator (VOA)  1231  and VOA  1232  may be used to reduce the power levels of egress optical data signal  1225  or ingress optical data signal  1224 . The power reduction may done by absorption, reflection, diffusion, scattering, deflection, diffraction, and dispersion, of egress optical data signal  1225  or ingress optical data signal  1224 . VOA  1231  and VOA  1232  typically have a working wavelength range in which they absorb all light energy equally. In some embodiments VOA  1231  and VOA  1232  utilize a length of high-loss optical fiber, that operates upon its input optical signal power level in such a way that its output signal power level is less than the input level. For example, egress optical data signal  1225  may have an input power level to VOA  1231  that may be greater than the output power level of egress optical data signal  1240  as it is output from VOA  1231 . Similarly if egress optical data signal  1225  is transmitted on connector  1227 , egress optical data signal  1225  may have an input power level to VOA  1232  that may be greater than the output power level of egress optical data signal  1241 . In some embodiments, the output power level of egress optical data signal  1240  may be greater than the output power level of egress optical data signal  1241 , and vice versa. The difference in output power levels between egress optical data signal  1240  and egress optical data signal  1241  may depend on the mode of primary fiber  1235  and secondary fiber  1236 . VOA  1232  may have a similar functionality to that of VOA  1231 . 
     The variability of the output power level of VOA  1231  and VOA  1232  may be achieved using a fiber coupler, where some of the power is not sent to the port that outputs, but to another port. Another possibility is to exploit variable coupling losses, which are influenced by variable positioning of a fiber end. For example, the transverse position of the output fiber or the width of an air gap between two fibers may be varied, obtaining a variable loss without a strong wavelength dependence. This principle may be used for single-mode fibers. VOA  1231  and VOA  1232  may be based on some piece of doped fiber, exhibiting absorption within a certain wavelength range. 
     The operation of headend  1201  may be described by way of the processing of upstream optical data signals received at headend  1201  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  1235  or secondary fiber  1236  depending on the position of switch  1226 . 
     Because the multi-wavelength ingress optical data signal is routed to port  1223  of WDM  1220 , and is altered negligibly between connector  1228  and port  1223  or connector  1227  and port  1223 , depending on the position of switch  1226 , the multi-wavelength ingress optical data signal may be substantially the same as ingress optical data signal  1224 . The multi-wavelength ingress optical data signal may traverse connector  1228  and switch  1226 , before entering WDM  1220  via port  1223  if switch  1226  is connected to connector  1228 . The multi-wavelength ingress optical data signal may traverse connector  1227  and switch  1226 , before entering WDM  1220  via port  1223  if switch  1226  is connected to connector  1227 . WDM  1220  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from ingress optical data signal  1224 . WDM  1220  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1218  to PON connector  1202  via port  1219 . WDM  1220  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1222 ) out of port  1221  to OPA  1214 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1222  may be received by OPA  1214 . The one or more optical data signals 10 GbE UP  1222  may comprise 10 GbE optical data signals. A gain associated OPA  1214  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1215 . The one or more optical data signals 10 GbE UP  1222  may be amplified by OPA  1214 , and OPA  1214  may output multi-wavelength upstream optical data signal  1212  to WDM  1210 . 
     WDM  1210  may receive the multi-wavelength upstream optical data signal  1212  on port  1209  of WDM  1210 , and may output one or more optical data signals 10 GbE UP  1207  to DWDM  1205 . The one or more optical data signals 10 GbE UP  1207  are substantially the same as multi-wavelength upstream optical data signal  1212 . WDM  1210  may function as a circulator when receiving multi-wavelength upstream optical data signal  1212  on port  1209  and outputting the one or more optical data signals 10 GbE UP  1207  on port  1208 . The one or more optical data signals 10 GbE UP  1207  may be received by DWDM  1205 . 
     The one or more optical data signals 10 GbE UP  1207  may comprise 10 GbE optical data signals. DWDM  1205  may demultiplex the one or more optical data signals 10 GbE UP  1207  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1207 . More specifically, the one or more optical data signals 10 GbE UP  1207  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1205  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1204 . Each of the transponders of 20×10 GbE UP  1204  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1204  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  13    depicts an access network diagram of an OCML headend comprising WDMs, a DWDM, optical amplifiers, and dispersion control modules (DCMs), in accordance with the disclosure.  FIG.  13    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  13   , headend  1301  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  1305 ), a first WDM (e.g., WDM  1313 ), a second WDM (e.g., WDM  1319 ), a third WDM (e.g., WDM  1323 ), a GPON/EPON connector (e.g., GPON/EPON  1324 ), a booster amplifier BOA (e.g., BOA  1316 ), an optical pre-amplifier (OPA) (e.g., OPA  1342 ), a variable optical attenuator (VOA) (e.g., VOA  1321 ), an optical switch  1326  to feed a primary optical fiber (e.g., Primary Fiber  1330 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1331 ), and a dispersion control module (DCM) (e.g., DCM  1308 ). DWDM  1305  may be similar in functionality to DWDM  106  and WDM  1313 , WDM  1319 , and WDM  1323  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE and GPON/EPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     The EPON signals may operate with the same optical frequencies as GPON and time division multiple access (TDMA). The raw line data rate is 1.25 Gbits/s in both the downstream and upstream directions. EPON is fully compatible with other Ethernet standards, so no conversion or encapsulation is necessary when connecting to Ethernet-based networks on either end. The same Ethernet frame is used with a payload of up to 1518 bytes. EPON may not use a carrier sense multiple access (CSMA)/collision detection (CD) access method used in other versions of Ethernet. There is a 10-Gbit/s Ethernet version designated as 802.3ay. The line rate may be 10.3125 Gbits/s. The primary mode is 10 Gbits/s upstream as well as downstream. A variation uses 10 Gbits/s downstream and 1 Gbit/s upstream. The 10-Gbit/s versions use different optical wavelengths on the fiber, 1575 to 1591 nm downstream and 1260 to 1280 nm upstream so the 10-Gbit/s system can be wavelength multiplexed on the same fiber as a standard 1-Gbit/s system. 
     In one aspect, headend  1301  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1303 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1304 ). 20×10 GbE DS  1303  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1304  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  1303  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  1304  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  1301  may be described by way of the processing of downstream optical data signals transmitted from headend  1301  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1303  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1303  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1303  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1305  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1307 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal 10 GbE DS  1307  may be a 10 GbE optical data signal. More specifically, DWDM  1305  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1307 , may be input to DCM  1308 . 10 GbE DS  1307  may be input into DCM  1308  to compensate for dispersion that 10 GbE DS  1307  may experience after being amplified by BOA  1316  and multiplexed by WDM  1323 , with other optical data signals, that are downstream from the DCM. The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  1301  over a fiber connecting headend  1301  to a field hub or outside plant. In some embodiments, DCM  1308  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  1308  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  1308  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. DCM  1308  may output a dispersion controlled version of 10 GbE DS  1307  as 10 GbE DS  1310 . 
     WDM  1313  may be a three port circulator, that receives multi-wavelength downstream optical data signal 10 GbE DS  1310  on port  1311 , and outputs multi-wavelength downstream optical data signal 10 GbE DS  1310 , on port  1314  as multi-wavelength downstream optical data signal 10 GbE DS  1315  to BOA  1316 . 
     BOA  1316  may have a gain that is based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, BOA  1316  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain BOA  1316  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1330  and/or the length of secondary fiber  1331 ). Multi-wavelength downstream optical data signal 10 GbE DS  1315  may be amplified by BOA  1316 , and BOA  1316  may output multi-wavelength downstream optical data signal 10 GbE DS  1317  to port  1318  of WDM  1319 . WDM  1319  outputs a multi-wavelength downstream optical data signal (e.g., multi-wavelength downstream optical data signal 10 GbE DS  1340 ) from port  1320 , which may be substantially the same as multi-wavelength downstream optical data signal 10 GbE DS  1317 . Multi-wavelength downstream optical data signal 10 GbE DS  1340  may be input to variable optical amplifier (VOA)  1321 . 
     VOA  1321  may be used to reduce the power levels of multi-wavelength downstream optical data signal 10 GbE DS  1340 . The power reduction may done by absorption, reflection, diffusion, scattering, deflection, diffraction, and dispersion, of multi-wavelength downstream optical data signal 10 GbE DS  1340 . VOA  1321  typically have a working wavelength range in which they absorb all light energy equally. In some embodiments VOA  1321  utilizes a length of high-loss optical fiber, that operates upon its input optical signal power level in such a way that its output signal power level is less than the input level. For example, multi-wavelength downstream optical data signal 10 GbE DS  1340  may have an input power level to VOA  1321  that may be greater than the output power level of multi-wavelength downstream optical data signal 10 GbE DS  1339 . 
     The variability of the output power level of VOA  1321  may be achieved using a fiber coupler, where some of the power is not sent to the port that outputs, but to another port. Another possibility is to exploit variable coupling losses, which are influenced by variable positioning of a fiber end. For example, the transverse position of the output fiber or the width of an air gap between two fibers may be varied, obtaining a variable loss without a strong wavelength dependence. This principle may be used for single-mode fibers. VOA  1321  may be based on some piece of doped fiber, exhibiting absorption within a certain wavelength range. 
     WDM  1323  may multiplex multi-wavelength downstream optical data signal 10 GbE DS  1339  and one or more EPON, and/or GPON optical data signals. The EPON and/or GPON optical data signals may be received on a GPON/EPON connector (e.g., GPON/EPON  1324 ) from PON port  1302 . The resulting multiplexed optical data signal may be referred to as egress optical data signal  1335 . 
     Egress optical data signal  1335  may be output by WDM  1323  and optical switch  1326  may switch egress optical data signal  1335  onto connector  1327  or connector  1334  depending on the position of switch  1326 . In some embodiments, connector  1327  may be a primary connector and connector  1334  may be a secondary connector or a backup connector. Wavelength monitoring connector  1328  may connect connector  1327  to a first port of wavelength-monitoring ports  1344 , and wavelength monitoring connector  1333  may connect connector  1334  to a second port of wavelength-monitoring ports  1344 . Wavelength-monitoring ports  1344  may monitor the wavelengths in egress optical data signal  1335  via connector  1327  or connector  1334  depending on the position of switch  1326 . Egress optical data signal  1335  may exit headend  1301  via connector  1327  connected to primary fiber  1330 , and may be received on a first connector in the field hub or outside plant. Egress optical data signal  1335  may exit headend  1301  via connector  1334  connected to secondary fiber  1331 , and may be received on a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     The operation of headend  1301  may be described by way of the processing of upstream optical data signals received at headend  1301  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal or a 10XGPON may be an upstream optical data signal received on primary fiber  1330  or secondary fiber  1331  depending on the position of switch  1326 . 
     Multi-wavelength ingress optical data signal  1336  may traverse connector  1327  and switch  1326 , before entering WDM  1323  via port  1337  if switch  1326  is connected to connector  1327 . Multi-wavelength ingress optical data signal  1336  may traverse connector  1334  and switch  1326 , before entering WDM  1323  via port  1337  if switch  1326  is connected to connector  1327 . WDM  1323  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from multi-wavelength ingress optical data signal  1336 . WDM  1323  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1324  to PON connector  1302  via port  1325 . WDM  1323  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1341 ) out of port  1338  to OPA  1342 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1341  may be received by OPA  1342 . The one or more optical data signals 10 GbE UP  1341  may comprise 10 GbE optical data signals. A gain associated OPA  1342  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1316 . The one or more optical data signals 10 GbE UP  1341  may be amplified by OPA  1342 , and OPA  1342  may output multi-wavelength upstream optical data signal  1343  to WDM  1313 . 
     WDM  1313  may receive the multi-wavelength upstream optical data signal  1343  on port  1312 , and may output one or more optical data signals 10 GbE UP  1309  to DCM  1308 . DCM  1308  may perform one or more operations on one or more optical data signals 10 GbE UP  1309  to compensate for any dispersion that may have been introduced by circuit components (e.g., WDM  1313 , OPA  1342 , or WDM  1323 ) or imperfections or issues with an optical fiber (e.g., primary fiber  1330  or secondary fiber  1331 ). DCM  1308  may output one or more optical data signals 10 GbE UP  1306  to DWDM  1305 . The one or more optical data signals 10 GbE UP  1309  are substantially the same as multi-wavelength upstream optical data signal  1343 . WDM  1313  may function as a circulator when receiving multi-wavelength upstream optical data signal  1343  on port  1312 . The one or more optical data signals 10 GbE UP  1306  may be received by DWDM  1305 . 
     The one or more optical data signals 10 GbE UP  1306  may comprise 10 GbE optical data signals. DWDM  1305  may demultiplex the one or more optical data signals 10 GbE UP  1306  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1306 . More specifically, the one or more optical data signals 10 GbE UP  1306  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1305  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1304 . Each of the transponders of 20×10 GbE UP  1304  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1304  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  14    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure.  FIG.  14    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  14   , headend  1401  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  1405 ), a first WDM (e.g., WDM  1410 ), a second WDM (e.g., WDM  1418 ), a first DCM (e.g., DCM  1413 ), a second DCM  1438 , a GPON/EPON connector (e.g., GPON/EPON  1420 ), a booster amplifier BOA (e.g., BOA  1415 ), an optical pre-amplifier (OPA) (e.g., OPA  1436 ), a first variable optical attenuator (VOA) (e.g., VOA  1424 ), a second VOA (e.g., VOA  1429 ), and an optical switch  1421  to feed a primary optical fiber (e.g., Primary Fiber  1426 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1427 ). DWDM  1405  may be similar in functionality to DWDM  106  and WDM  1410  and WDM  1418  may be similar in functionality to WDM  108 . DCM  1413  and DCM  1438  may be similar in functionality to DCM  112 . The disclosure provides a method of transporting multiple 10 GbE and GPON/EPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     The EPON signals may operate with the same optical frequencies as GPON and time division multiple access (TDMA). The raw line data rate is 1.25 Gbits/s in both the downstream and upstream directions. EPON is fully compatible with other Ethernet standards, so no conversion or encapsulation is necessary when connecting to Ethernet-based networks on either end. The same Ethernet frame is used with a payload of up to 1518 bytes. EPON may not use a carrier sense multiple access (CSMA)/collision detection (CD) access method used in other versions of Ethernet. There is a 10-Gbit/s Ethernet version designated as 802.3ay. The line rate may be 10.3125 Gbits/s. The primary mode is 10 Gbits/s upstream as well as downstream. A variation uses 10 Gbits/s downstream and 1 Gbit/s upstream. The 10-Gbit/s versions use different optical wavelengths on the fiber, 1571 to 1591 nm downstream and 1260 to 1280 nm upstream so the 10-Gbit/s system can be wavelength multiplexed on the same fiber as a standard 1-Gbit/s system. 
     In one aspect, headend  1401  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1403 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1404 ). 20×10 GbE DS  1403  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1404  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  1403  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  1404  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  1401  may be described by way of the processing of downstream optical data signals transmitted from headend  1401  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1403  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1403  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1403  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1405  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1407 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal 10 GbE DS  1407  may be a 10 GbE optical data signal. More specifically, DWDM  1405  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1407 , may be input to WDM  1410 . WDM  1410  may be a three port circulator, that receives multi-wavelength downstream optical data signal 10 GbE DS  1407  on port  1408 , and outputs multi-wavelength downstream optical data signal 10 GbE DS  1407 , on port  1408  as multi-wavelength downstream optical data signal 10 GbE DS  1412  on port  1411  to DCM  1413 . 
     Multi-wavelength downstream optical data signal 10 GbE DS  1412  may be input into DCM  1413  to compensate for dispersion that 10 GbE DS  1412  may experience after being amplified by BOA  1415  and multiplexed by WDM  1413 , with other optical data signals, that are downstream from DCM  1413 . The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  1401  over a fiber connecting headend  1401  to a field hub or outside plant. In some embodiments, DCM  1413  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  1413  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  1413  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. DCM  1413  may output a dispersion controlled version of 10 GbE DS  1412  as 10 GbE DS  1414 . 
     BOA  1415  may have a gain that is based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, BOA  1415  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain BOA  1415  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1426  and/or the length of secondary fiber  1427 ). Multi-wavelength downstream optical data signal 10 GbE DS  1414  may be amplified by BOA  1415 , and BOA  1415  may output multi-wavelength downstream optical data signal 10 GbE DS  11416  to port  1417  of WDM  1418 . 
     WDM  1418  may multiplex multi-wavelength downstream optical data signal 10 GbE DS  1416  and one or more EPON, and/or GPON optical data signals. The EPON and/or GPON optical data signals may be received on a GPON/EPON connector (e.g., GPON/EPON  1420 ) from PON port  1402 . The resulting multiplexed optical data signal may be referred to as egress optical data signal  1432 . 
     Egress optical data signal  1432  may be output by WDM  1418  and optical switch  1421  may switch egress optical data signal  1432  onto connector  1422  or connector  1431  depending on the position of switch  1421 . In some embodiments, connector  1422  may be a primary connector and connector  1431  may be a secondary connector or a backup connector. Wavelength monitoring connector  1423  may connect connector  1422  to a first port of wavelength-monitoring ports  1440 , and wavelength monitoring connector  1430  may connect connector  1431  to a second port of wavelength-monitoring ports  1440 . Wavelength-monitoring ports  1440  may monitor the wavelengths in egress optical data signal  1432  via connector  1422  or connector  1431  depending on the position of switch  1421 . Egress optical data signal  1432  may exit headend  1401  either via connector  1422  connected to primary fiber  1426 , as egress optical data signal  1441 , or via connector  1431  connected to secondary fiber  1427 , as egress optical data signal  1442 , depending on the position of switch  1421 . Egress optical data signal  1432  may be transmitted as, egress optical data signal  1441 , on primary fiber  1426  to a first connector in the field hub or outside plant. Egress optical data signal may be transmitted as, egress optical data signal  1442 , on secondary fiber  1427  to a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     Variable optical attenuator (VOA)  1424  and VOA  1429  may be used to reduce the power levels of egress optical data signal  1432  or ingress optical data signal  1433 . The power reduction may done by absorption, reflection, diffusion, scattering, deflection, diffraction, and dispersion, of egress optical data signal  1432  or ingress optical data signal  1433 . VOA  1424  and VOA  1429  typically have a working wavelength range in which they absorb all light energy equally. In some embodiments VOA  1424  and VOA  1429  utilize a length of high-loss optical fiber, that operates upon its input optical signal power level in such a way that its output signal power level is less than the input level. For example, egress optical data signal  1432  may have an input power level to VOA  1424  that may be greater than the output power level of egress optical data signal  1441  as it is output from VOA  1424 . Similarly if egress optical data signal  1432  is transmitted on connector  1431 , egress optical data signal  1432  may have an input power level to VOA  1429  that may be greater than the output power level of egress optical data signal  1442 . In some embodiments, the output power level of egress optical data signal  1441  may be greater than the output power level of egress optical data signal  1442 , and vice versa. The difference in output power levels between egress optical data signal  1441  and egress optical data signal  1442  may depend on the mode of primary fiber  1426  and secondary fiber  1427 . VOA  1424  may have a similar functionality to that of VOA  1429 . 
     The variability of the output power level of VOA  1424  and VOA  1429  may be achieved using a fiber coupler, where some of the power is not sent to the port that outputs, but to another port. Another possibility is to exploit variable coupling losses, which are influenced by variable positioning of a fiber end. For example, the transverse position of the output fiber or the width of an air gap between two fibers may be varied, obtaining a variable loss without a strong wavelength dependence. This principle may be used for single-mode fibers. VOA  1424  and VOA  1429  may be based on some piece of doped fiber, exhibiting absorption within a certain wavelength range. 
     The operation of headend  1401  may be described by way of the processing of upstream optical data signals received at headend  1401  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  1426  or secondary fiber  1427  depending on the position of switch  1421 . 
     Because the multi-wavelength ingress optical data signal is routed to port  1434  of WDM  1418 , and is altered negligibly between connector  1422  and port  1434  or connector  1432  and port  1434 , depending on the position of switch  1421 , the multi-wavelength ingress optical data signal may be substantially the same as ingress optical data signal  1433 . The multi-wavelength ingress optical data signal may traverse connector  1422  and switch  1421 , before entering WDM  1418  via port  1434  if switch  1421  is connected to connector  1422 . The multi-wavelength ingress optical data signal may traverse connector  1431  and switch  1421 , before entering WDM  1418  via port  1434  if switch  1421  is connected to connector  1431 . WDM  1418  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from ingress optical data signal  1433 . WDM  1418  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1420  to PON connector  1402  via port  1419 . WDM  1418  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1435 ) out of port  1421  to OPA  1436 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1435  may be received by OPA  1436 . The one or more optical data signals 10 GbE UP  1435  may comprise 10 GbE optical data signals. A gain associated OPA  1436  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1415 . The one or more optical data signals 10 GbE UP  1435  may be amplified by OPA  1436 , and OPA  1436  may output multi-wavelength upstream optical data signal  1437  to DCM  1438 . 
     In some embodiments, DCM  1438  may be configured to balance positive and/or negative dispersion that may be introduced to a SONET/SDH egress optical data signal that may enter headend  1401  from 20×10 GbE UP  1404 . The SONET/SDH egress optical data signal may be an upstream signal from a field hub or outside plant destined for a MTC. For example, a customer premise may be connected to the field hub or outside plant and may send one or more packets via a SONET/SDH network to the field hub or outside plant which may in turn transmit the one or more packets using 10 GbE optical data signals to headend  1401 . The one or more packets may be destined for a company web server connected to the MTC via a backbone network. Because headend  1401  may be collocated in a STC that is connected to the MTC via an optical ring network, wherein the connection between the STC and MTC is a SONET/SDH optical network connection, DCM  1438  may be configured to compensate for positive and/or negative dispersion on the SONET/SDH optical network connection. That is DCM  1438  may be configured to reduce temporal broadening of the SONET/SDH egress optical data signal or temporal contraction of the SONET/SDH egress optical data signal. DCM  1438  may input 10 GbE UP  1437  and may output 10 GbE UP  1439  to WDM  1410 . 
     WDM  1410  may receive the multi-wavelength upstream optical data signal 10 GbE UP  1439  on port  1409  of WDM  1410 , and may output one or more optical data signals 10 GbE UP  1406  to DWDM  1405 . The one or more optical data signals 10 GbE UP  1406  are substantially the same as multi-wavelength upstream optical data signal 10 GbE UP  1439 . WDM  1410  may function as a circulator when receiving multi-wavelength upstream optical data signal 10 GbE UP  1439  on port  1409  and may output the one or more optical data signals 10 GbE UP  1406  on port  1408 . The one or more optical data signals 10 GbE UP  1406  may be received by DWDM  1405 . 
     The one or more optical data signals 10 GbE UP  1406  may comprise 10 GbE optical data signals. DWDM  1405  may demultiplex the one or more optical data signals 10 GbE UP  1406  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1406 . More specifically, the one or more optical data signals 10 GbE UP  1406  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1405  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1404 . Each of the transponders of 20×10 GbE UP  1404  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1404  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  15    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure.  FIG.  15    shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  15   , headend  1501  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  1506 ), a first WDM (e.g., WDM  1513 ), a second WDM (e.g., WDM  1524 ), a GPON/EPON connector (e.g., GPON/EPON  1528 ), a booster amplifier BOA (e.g., BOA  1516 ), an optical pre-amplifier (OPA) (e.g., OPA  1544 ), an optical switch  1530  to feed a primary optical fiber (e.g., Primary Fiber  1550 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1551 ). The disclosure provides a method of transporting multiple 10 GbE and GPON/EPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in the MTC facility. A field hub or outside plant may house a multiplexer-demultiplexer (MDM) (e.g., MDM  1591 ). 
     The EPON signals may operate with the same optical frequencies as GPON and time division multiple access (TDMA). The raw line data rate is 1.25 Gbits/s in both the downstream and upstream directions. 
     EPON is fully compatible with other Ethernet standards, so no conversion or encapsulation is necessary when connecting to Ethernet-based networks on either end. The same Ethernet frame is used with a payload of up to 1518 bytes. EPON may not use a carrier sense multiple access (CSMA)/collision detection (CD) access method used in other versions of Ethernet. 
     There is a 10-Gbit/s Ethernet version designated as 802.3ay. The line rate may be 10.3125 Gbits/s. The primary mode is 10 Gbits/s upstream as well as downstream. A variation uses 10 Gbits/s downstream and 1 Gbit/s upstream. The 10-Gbit/s versions use different optical wavelengths on the fiber, 1571 to 1591 nm downstream and 1260 to 1280 nm upstream so the 10-Gbit/s system can be wavelength multiplexed on the same fiber as a standard 1-Gbit/s system. 
     In one aspect, headend  1501  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1503 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1504 ). 20×10 GbE DS  1503  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1504  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  1503  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  1504  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  1501  may be described by way of the processing of downstream optical data signals transmitted from headend  1501  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1503  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1503  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1503  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1506  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1508 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal 10 GbE DS  1508  may be a 10 GbE optical data signal. More specifically, DWDM  1506  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1508 , may be input to WDM  1513 . WDM  1513  may be a three port circulator, that receives multi-wavelength downstream optical data signal 10 GbE DS  1508  on port  1509 , and outputs multi-wavelength downstream optical data signal 10 GbE DS  1515 , on port  1514  as multi-wavelength downstream optical data signal 10 GbE DS  1515  to BOA  1516 . 
     BOA  1516  may have a gain that is based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, BOA  1516  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain BOA  1516  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1550  and/or the length of secondary fiber  1551 ). Multi-wavelength downstream optical data signal 10 GbE DS  1515  may be amplified by BOA  1516 , and BOA  1516  may output multi-wavelength downstream optical data signal 10 GbE DS  1518  to port  1520  of WDM  1524 . WDM  1524  outputs an egress optical data signal from port  1541 , which may be a multi-wavelength optical data signal comprising 10 GbE, EPON, and/or GPON optical data signals. The EPON and/or GPON optical data signals may be received on a GPON/EPON connector (e.g., GPON/EPON  1528 ) from PON port  1502 . 
     Egress optical data signal  1539  may be output by WDM  1524  and optical switch  1530  may switch egress optical data signal  1539  onto connector  1532  or connector  1538  depending on the position of switch  1530 . In some embodiments, connector  1532  may be a primary connector and connector  1538  may be a secondary connector or a backup connector. Wavelength monitoring connector  1534  may connect connector  1532  to a first port of wavelength-monitoring ports  1548 , and wavelength monitoring connector  1537  may connect connector  1538  to a second port of wavelength-monitoring ports  1548 . Wavelength-monitoring ports  1548  may monitor the wavelengths in egress optical data signal  1539  via connector  1532  or connector  1538  depending on the position of switch  1530 . Egress optical data signal  1539  may exit headend  1501  either via connector  1532  connected to primary fiber  1550 , or via connector  1538  connected to secondary fiber  1551 , depending on the position of switch  1530 . Egress optical data signal  1539  may be transmitted on primary fiber  1550  to an optical splitter (e.g., the optical splitter  1593 ) inside of or collocated with a MDM (e.g., the MDM  1591 ). Egress optical data signal  1539  may be transmitted on secondary fiber  1551  to the optical splitter  1593 . 
     Egress optical data signal  1539  may be received at optical splitter  1593  as an ingress optical data signal. Optical splitter  1593  may also be referred to as a beam splitter, and may comprise one or more quartz substrates of an integrated waveguide optical power distribution device. Optical splitter  1593  may be a passive optical network device. It may be an optical fiber tandem device comprising one or more input terminals and one or more output terminals. Optical splitter  1593  may be Fused Biconical Taper (FBT) splitter or Planar Lightwave Circuit (PLC) splitter. Optical splitter  1593  may be a balanced splitter wherein optical splitter  1593  comprises 2 input fibers and one or more output fibers over which the ingress optical data signal may be spread proportionally. In some embodiments, the ingress optical data signal may not be spread proportionally across the output fibers of optical splitter  1593 . In some embodiments, optical splitter  1593  may comprise 2 input fibers and 2 output fibers. A first input fiber of optical splitter  1593  may be connected to primary fiber  1550  and a second input fiber of optical splitter  1593  may be connected to secondary fiber  1551 . 
     A first output fiber of optical splitter  1593  may be connected to a filter (e.g., C-band block  1592 ) that filters out packets of light, in the ingress optical data signal, with wavelengths between 1530 nm and 1565 nm. This range of wavelengths may coincide with a C-band of wavelengths. In some other embodiments, the filter may filter out packets of light with wavelengths not inclusive of the wavelengths between 1260 nm and 1520 nm and not inclusive of wavelengths between 1570 nm and 1660 nm. The packets of light with wavelengths inclusive of the wavelengths between 1260 nm and 1520 nm and inclusive of wavelengths between 1570 nm and 1660 nm, may correspond to the wavelengths of the packets of light carrying the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1528 . More specifically, optical splitter  1593 , may receive one or more downstream EPON and/or GPON optical data signals  1560 , in the ingress optical data signal, that corresponds to the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1528 . In some embodiments, the one or more downstream EPON and/or GPON optical data signals  1560  may have the same wavelength as GPON DS  806 . Optical splitter  1593  may output the one or more downstream EPON and/or GPON optical data signals  1560 , received in the ingress optical data signal, to C-band block  1592 . 
     C-band block  1592  may output one or more downstream EPON and/or GPON optical data signals  1597  corresponding to the one or more downstream EPON and/or GPON optical data signals  1560  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. The C-band block  1592  may transmit the one or more downstream EPON and/or GPON optical data signals  1597  to an express port (not shown in  FIG.  15   ) collocated with, or attached to MDM  1591 . In some embodiments, the express port may be located within the MDM  1591 . 
     A second output fiber of optical splitter  1593  may be connected to coupled optical power (COP)  1594 . COP  1594  may be a PON device that monitors the coupled optical power between Optical Splitter  1593  and DWDM  1596 . In some embodiments, the coupled optical power may be a percentage value. For instance, the coupled optical power may be 1%. Optical splitter  1593 , may receive one or more downstream 10 GbE optical data signals, in the ingress optical data signal, that corresponds to 10 GbE DS  1508 . In some embodiments, the one or more downstream 10 GbE optical data signals may have the same wavelength as 10 GbE  1503 . Optical splitter  1593  may output the one or more downstream 10 GbE optical data signals  1563 , received in the ingress optical data signal, to COP  1594 . COP  1594  may output a first percentage of the one or more downstream 10 GbE optical data signals  1563  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1595 ). The first percentage may be a percentage of the one or more downstream 10 GbE optical data signals  1563  tested by the 10 GbE upstream and downstream test ports. The first percentage of the one or more downstream 10 GbE optical data signals  1563  may be a monitoring signal used by a spectrum analyzer to measure optical power levels of a specific wavelength. The first percentage of the one or more downstream 10 GbE optical data signals  1563  may also be used by the spectrum analyzer to analyze certain characteristics of the wavelengths of the first percentage of the one or more downstream 10 GbE optical data signals  1563 . COP  1594  may output a second percentage of the one or more downstream 10 GbE optical data signals  1565  to DWDM  1596 . Because the one or more downstream 10 GbE optical data signals  1565  may be a multi-wavelength downstream optical data signal DWDM  1596  may demultiplex the one or more downstream 10 GbE optical data signals  1565  into individual optical data signals in accordance with the individual wavelengths of the one or more downstream 10 GbE optical data signals  1565 . More specifically, the one or more downstream 10 GbE optical data signals  1565  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1596  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  1598 . Each of the transponders of 20×10 GbE DS  1598  may be in a RPD (not shown) and may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. In some embodiments, the RPD may be similar in functionality to Remote PHY Node  207 . The RPD may convert the SONET/SDH optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. MDM  1591  may be similar in functionality to MDM  208  and may be connected to the RPD in a way similar to the connection between MDM  208  and Remote PHY Node  207 . 
     The operation of MDM  1591  may be further described by way of the processing of an upstream optical data signal transmitted to headend  1501 . Each of the transponders of 20×10 GbE UP  1599  may receive a SONET/SDH optical data signal and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. Each of the transponders of 20×10 GbE UP  1599  may receive the SONET/SDH optical data signal from the RPD. The RPD may also convert one or more electrical signals into the SONET/SDH optical data signal. 
     More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  1599  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  1599  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1596  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength upstream optical data signal (e.g., multi-wavelength upstream optical data signal  1564 ) comprising the twenty corresponding second optical data signals. The multi-wavelength upstream optical data signal  1564  may be a 10 GbE optical data signal. More specifically, DWDM  1596  may multiplex the twenty corresponding second optical data signals onto the fiber connecting DWDM  1596  and COP  1594 , wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength upstream optical data signal  1564 , may be input to COP  1594 . COP  1594  may output a first percentage of the multi-wavelength upstream optical data signal  1564  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1595 ). The first percentage may be a percentage of the multi-wavelength upstream optical data signal  1564  tested by the 10 GbE upstream and downstream test ports COP  1594  may output a second percentage of the multi-wavelength upstream optical data signal  1564  to optical splitter  1593  as the multi-wavelength upstream optical data signal  1562 . 
     C-band block  1592  may receive one or more upstream EPON and/or GPON optical data signals  1566  from an express port (not shown in  FIG.  15   ) collocated with, or attached to MDM  1591 . In some embodiments, the express port may be located within the MDM  1591 . C-band block  1592  may filter out packets of light, in the one or more upstream EPON and/or GPON optical data signals  1566 , with wavelengths between 1530 nm and 1565 nm. Thus C-band block  1592  may output one or more upstream EPON and/or GPON optical data signals  1561  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. 
     Optical splitter  1593  may receive one or more upstream EPON and/or GPON optical data signals  1561 , and may also receive the multi-wavelength upstream optical data signal  1562 , and may multiplex the multi-wavelength of one or more upstream EPON and/or GPON optical data signals  1561  with the multi-wavelength upstream optical data signal  1562 . Optical splitter  1593  outputs an egress optical data signal, which may be a multi-wavelength optical data signal comprising 10 GbE, GPON/EPON optical data signals corresponding to the multiplexed multi-wavelength of one or more upstream EPON and/or GPON optical data signals  1561  and multi-wavelength upstream optical data signal  1562 . Optical splitter  1593  may output the egress optical data signal onto primary fiber  1550  connecting the optical splitter  1593  to port  1536 . Optical splitter  1593  may also output the egress optical data signal onto secondary fiber  1551  connecting the optical splitter  1593  to port  1546 . 
     The operation of headend  1501  may be described by way of the processing of upstream optical data signals received at headend  1501  from MDM  1591 . For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  1550  or secondary fiber  1551  depending on the position of switch  1530 . The upstream optical data signal may be substantially the same as the egress optical data signal. 
     The multi-wavelength ingress optical data signal  1540  may traverse connector  1532  and switch  1530 , before entering WDM  1524  via port  1541  if switch  1530  is connected to connector  1532 . The multi-wavelength ingress optical data signal may traverse connector  1538  and switch  1530 , before entering WDM  1524  via port  1541  if switch  1530  is connected to connector  1538 . WDM  1524  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from ingress optical data signal  1540 . WDM  1524  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1528  to PON connector  1502  via port  1522 . WDM  1524  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1542 ) out of port  1526  to OPA  1544 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1542  may be received by OPA  1544 . The one or more optical data signals 10 GbE UP  1542  may comprise 10 GbE optical data signals. A gain associated OPA  1544  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1516 . The one or more optical data signals 10 GbE UP  1542  may be amplified by OPA  1544 , and OPA  1544  may output multi-wavelength upstream optical data signal  1512  to WDM  1513 . 
     WDM  1513  may receive the multi-wavelength upstream optical data signal  1512  on port  1510  of WDM  1513 , and may output one or more optical data signals 10 GbE UP  1511  to DWDM  1506 . The one or more optical data signals 10 GbE UP  1511  are substantially the same as multi-wavelength upstream optical data signal  1512 . WDM  1513  may function as a circulator when receiving multi-wavelength upstream optical data signal  1512  on port  1510  and outputting the one or more optical data signals 10 GbE UP  1511  on port  1509 . The one or more optical data signals 10 GbE UP  1511  may be received by DWDM  1506 . 
     The one or more optical data signals 10 GbE UP  1511  may comprise 10 GbE optical data signals. DWDM  1506  may demultiplex the one or more optical data signals 10 GbE UP  1511  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1511 . More specifically, the one or more optical data signals 10 GbE UP  1511  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1506  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1504 . Each of the transponders of 20×10 GbE UP  1504  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1504  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  16    depicts a process of transmitting optical signals with the OCML headend, in accordance with the disclosure. As shown in  FIG.  16   , headend  1601  is a smart integrated OCML headend, which is a circuit, comprising one or more EDFAs (e.g., booster optical amplifier (BOA)  1616  and optical pre-amplifier (OPA)  1633 ), a DWDM (e.g., DWDM  1605 ), one or more WDMs (e.g., WDM  1610  and  1619 ), one or more DCMs (e.g., DCM  1615  and  1635 ), and an optical switch  1625  to feed a primary optical fiber (e.g., Primary Fiber  1637 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1638 ). The disclosure provides a method of transporting multiple 10 GbE and GPON/XGPON/10GEPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  1691 ). 
     In one aspect, headend  1601  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1603 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1604 ). 20×10 GbE DS  1603  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1604  may receive upstream data over 10 GbE wavelengths. Headend  1601  may have a connector (e.g., PON  1602 ), that may transmit and receive GPON and/or EPON signals on a GPON/EPON connector (e.g., GPON/EPON  1618 ). Headend  1601  may also comprise two wavelength-monitoring ports (e.g., wavelength-monitoring ports  1636 ), a primary optical fiber (e.g., primary optical fiber  1637 ) and a secondary optical fiber (e.g., secondary optical fiber  1638 ) that transmit and receive a plurality of multi-wavelength 10 GbE and GPON/EPON optical signals. Primary optical fiber  1637  and secondary optical fiber  1638  may transmit a first plurality of multi-wavelength 10 GbE, GPON, and/or XGPON/10GEPON optical signals from headend  1601  to a multiplexer-demultiplexer (MDM) in an outside plant (e.g., MDM  1691 ), and may receive a second plurality of multi-wavelength 10 GbE, GPON, and/or EPON optical signals from MDM  1691 . 
     In one aspect, headend  1601  can transmit and receive up to twenty bi-directional 10 GbE optical data signals, but the actual number of optical data signals may depend on operational needs. That is, headend  1601  can transport more or less than twenty 10 GbE downstream optical signals, or more or less than twenty 10 GbE upstream optical data signals, based on the needs of customers&#39; networks (e.g., Remote PHY Network  216 , Enterprise Network  218 , Millimeter Wave Network  214 ). These customer networks may be connected to headend  1601  through an optical ring network (e.g., metro access optical ring network  206 ). 
     The operation of headend  1601  may be described by way of the processing of downstream optical data signals transmitted from headend  1601  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1603  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1603  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1603  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1605  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1606 ) comprising the twenty corresponding second optical data signals onto a fiber. More specifically, DWDM  1605  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength downstream optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1606 , may be input to a WDM (e.g. WDM  1610 ). WDM  1610  may be a three port wave division multiplexer (WDM), or a three port circulator, that receives 10 GbE DS  1606  on port  1608  and outputs 10 GbE DS  1606  on port  1611  as 10 GbE DS  1614 . 10 GbE DS  1614  may be substantially the same as 10 GbE DS  1606  because WDM  1610  may function as a circulator when 10 GbE DS  1606  is input on port  1608 . 
     10 GbE DS  1614  may be input into a DCM (e.g., DCM  1615 ) to compensate for dispersion that 10 GbE DS  1614  may experience after being amplified by an EDFA and multiplexed by a WDM, with other optical data signals, that are downstream from the DCM. The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  1601  over a fiber connecting headend  1601  to a field hub or outside plant containing MDM  1691 . In some embodiments, DCM  1615  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  1615  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  1615  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. 
     DCM  1615  may input 10 GbE DS  1614  and may output 10 GbE DS  1653  to an EDFA (e.g., BOA  1616 ). A gain of BOA  1616  may be based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, the gain of BOA  1616  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of BOA  1616  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1637  and/or the length of secondary fiber  1638 ). 10 GbE DS  1653  may be amplified by BOA  1616 , and BOA  1616  may output 10 GbE DS  1620  to port  1617  of WDM  1619 . 
     WDM  1619  may be a WDM that may multiplex 10 GbE DS  1620  with one or more PON signals received on (GPON/EPON  1618 ). 10 GbE DS  1620  may be a multi-wavelength optical data signal, wherein the wavelengths comprise the same wavelengths as 10 GbE DS  1606 . In some embodiments, the wavelengths of the multi-wavelength optical data signal 10 GbE DS  1620  may be within the conventional c band of wavelengths, which may include wavelengths within the 1520 nm-1565 nm range. GPON  1602  may be a fiber carrying a GPON optical data signal with a wavelength of 1490 nm. The GPON signal may be input to WDM  1619  on port  1671 . WDM  1619  outputs an egress optical data signal from port  1622 , which may be a multi-wavelength optical data signal comprising 10 GbE, EPON, and GPON optical data signals. WDM  1619  may multiplex 10 GbE DS  1620 , EPON optical data signals, and GPON optical data signals the same way DWDM  1605  multiplexes optical data signals. The egress optical data signal (e.g., egress optical data signal  1624 ) may be output on port  1622  of WDM  1619  and optical switch  1625  may switch egress optical data signal  1624  out of connector  1626  or connector  1631 . In some embodiments, connector  1626  may be a primary connector and connector  1631  may be a secondary connector or a backup connector. Wavelength monitoring connector  1627  may connect connector  1626  to a first port of wavelength-monitoring ports  1636 , and wavelength monitoring connector  1629  may connect connector  1631  to a second port of wavelength-monitoring ports  1636 . Wavelength-monitoring ports  1636  may monitor the wavelengths in egress optical data signal  1624  via connector  1626  or connector  1631  depending on the position of switch  1625 . Egress optical data signal  1624  may exit headend  1601  either via connector  1626  connected to primary fiber  1637  or via connector  1631  connected to secondary fiber  1638  depending on the position of switch  1625 . Egress optical data signal  1624  may be transmitted on primary fiber  1637  to a first connector and optical splitter (e.g., the optical splitter  1693 ) inside of or collocated with a MDM (e.g., the MDM  1691 ). Egress optical data signal  1538  may be transmitted on secondary fiber  1638  to a second connector in optical splitter  1693 . 
     Egress optical data signal  1624  may be received at optical splitter  1693  as an ingress optical data signal. Optical splitter  1693  may also be referred to as a beam splitter, and may comprise one or more quartz substrates of an integrated waveguide optical power distribution device. Optical splitter  1693  may be a passive optical network device. It may be an optical fiber tandem device comprising one or more input terminals and one or more output terminals. Optical splitter  1639  may be Fused Biconical Taper (FBT) splitter or Planar Lightwave Circuit (PLC) splitter. Optical splitter  1693  may be a balanced splitter wherein optical splitter  1693  comprises 2 input fibers and one or more output fibers over which the ingress optical data signal may be spread proportionally. In some embodiments, the ingress optical data signal may not be spread proportionally across the output fibers of optical splitter  1693 . In some embodiments, optical splitter  1693  may comprise 2 input fibers and 2 output fibers. A first input fiber of optical splitter  1693  may be connected to primary fiber  1637  and a second input fiber of optical splitter  1693  may be connected to secondary fiber  1638 . 
     A first output fiber of optical splitter  1693  may be connected to a filter (e.g., C-band block  1692 ) that filters out packets of light, in the ingress optical data signal, with wavelengths between 1530 nm and 1565 nm. This range of wavelengths may coincide with a C-band of wavelengths. In some other embodiments, the filter may filter out packets of light with wavelengths not inclusive of the wavelengths between 1260 nm and 1520 nm and not inclusive of wavelengths between 1570 nm and 1660 nm. The packets of light with wavelengths inclusive of the wavelengths between 1260 nm and 1520 nm and inclusive of wavelengths between 1570 nm and 1660 nm, may correspond to the wavelengths of the packets of light carrying the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1618 . More specifically, optical splitter  1693 , may receive one or more downstream EPON and/or GPON optical data signals  1660 , in the ingress optical data signal, that corresponds to the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1618 . In some embodiments, the one or more downstream EPON and/or GPON optical data signals  1660  may have the same wavelength as GPON DS  806 . Optical splitter  1693  may output the one or more downstream EPON and/or GPON optical data signals  1660 , received in the ingress optical data signal, to C-band block  1692 . 
     C-band block  1692  may output one or more downstream EPON and/or GPON optical data signals  1697  corresponding to the one or more downstream EPON and/or GPON optical data signals  1660  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. The C-band block  1692  may transmit the one or more downstream EPON and/or GPON optical data signals  1697  to an express port (not shown in  FIG.  16   ) collocated with, or attached to MDM  1691 . In some embodiments, the express port may be located within the MDM  1691 . 
     A second output fiber of optical splitter  1693  may be connected to coupled optical power (COP)  1694 . COP  1694  may be a PON device that monitors the coupled optical power between Optical Splitter  1693  and DWDM  1696 . In some embodiments, the coupled optical power may be a percentage value. For instance, the coupled optical power may be 1%. Optical splitter  1693 , may receive one or more downstream 10 GbE optical data signals, in the ingress optical data signal, that corresponds to 10 GbE DS  1608 . In some embodiments, the one or more downstream 10 GbE optical data signals may have the same wavelength as 10 GbE  1603 . Optical splitter  1693  may output the one or more downstream 10 GbE optical data signals  1663 , received in the ingress optical data signal, to COP  1694 . COP  1694  may output a first percentage of the one or more downstream 10 GbE optical data signals  1663  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1695 ). The first percentage may be a percentage of the one or more downstream 10 GbE optical data signals  1663  tested by the 10 GbE upstream and downstream test ports. The first percentage of the one or more downstream 10 GbE optical data signals  1663  may be a monitoring signal used by a spectrum analyzer to measure optical power levels of a specific wavelength. The first percentage of the one or more downstream 10 GbE optical data signals  1663  may also be used by the spectrum analyzer to analyze certain characteristics of the wavelengths of the first percentage of the one or more downstream 10 GbE optical data signals  1663 . COP  1694  may output a second percentage of the one or more downstream 10 GbE optical data signals  1665  to DWDM  1696 . 
     Because the one or more downstream 10 GbE optical data signals  1665  may be a multi-wavelength downstream optical data signal DWDM  1696  may demultiplex the one or more downstream 10 GbE optical data signals  1665  into individual optical data signals in accordance with the individual wavelengths of the one or more downstream 10 GbE optical data signals  1665 . More specifically, the one or more downstream 10 GbE optical data signals  1665  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1696  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  1698 . Each of the transponders of 20×10 GbE DS  1698  may be in a RPD (not shown) and may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. In some embodiments, the RPD may be similar in functionality to Remote PHY Node  207 . The RPD may convert the SONET/SDH optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. MDM  1691  may be similar in functionality to MDM  208  and may be connected to the RPD in a way similar to the connection between MDM  208  and Remote PHY Node  207 . 
     The operation of MDM  1691  may be further described by way of the processing of an upstream optical data signal transmitted to headend  1601 . Each of the transponders of 20×10 GbE UP  1699  may receive a SONET/SDH optical data signal and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. Each of the transponders of 20×10 GbE UP  1699  may receive the SONET/SDH optical data signal from the RPD. The RPD may also convert one or more electrical signals into the SONET/SDH optical data signal. 
     More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  1699  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  1699  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1696  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength upstream optical data signal (e.g., multi-wavelength upstream optical data signal  1664 ) comprising the twenty corresponding second optical data signals. The multi-wavelength upstream optical data signal  1664  may be a 10 GbE optical data signal. More specifically, DWDM  1696  may multiplex the twenty corresponding second optical data signals onto the fiber connecting DWDM  1696  and COP  1694 , wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength upstream optical data signal  1664 , may be input to COP  1694 . COP  1694  may output a first percentage of the multi-wavelength upstream optical data signal  1664  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1695 ). The first percentage may be a percentage of the multi-wavelength upstream optical data signal  1664  tested by the 10 GbE upstream and downstream test ports. The first percentage of the multi-wavelength upstream optical data signal  1664  may be a monitoring signal used by a spectrum analyzer to measure optical power levels of a specific wavelength in the multi-wavelength upstream optical data signal  1664 . The first percentage of the multi-wavelength upstream optical data signal  1664  may also be used by the spectrum analyzer to analyze certain characteristics of the wavelengths of the first percentage of the multi-wavelength upstream optical data signal  1664 . COP  1694  may output a second percentage of the multi-wavelength upstream optical data signal  1664  to optical splitter  1693  as the multi-wavelength upstream optical data signal  1662 . 
     C-band block  1692  may receive one or more upstream EPON and/or GPON optical data signals  1666  from an express port (not shown in  FIG.  16   ) collocated with, or attached to MDM  1691 . In some embodiments, the express port may be located within the MDM  1691 . C-band block  1692  may filter out packets of light, in the one or more upstream EPON and/or GPON optical data signals  1666 , with wavelengths between 1530 nm and 1565 nm. Thus C-band block  1692  may output one or more upstream EPON and/or GPON optical data signals  1661  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. 
     Optical splitter  1693  may receive one or more upstream EPON and/or GPON optical data signals  1661 , and may also receive the multi-wavelength upstream optical data signal  1662 , and may multiplex the multi-wavelength of one or more upstream EPON and/or GPON optical data signals  1661  with the multi-wavelength upstream optical data signal  1662 . Optical splitter  1693  outputs an egress optical data signal, which may be a multi-wavelength optical data signal comprising 10 GbE, GPON/EPON optical data signals corresponding to the multiplexed multi-wavelength one or more upstream EPON and/or GPON optical data signals  1661  and multi-wavelength upstream optical data signal  1662 . Optical splitter  1693  may output the egress optical data signal onto primary fiber  1637  connecting the optical splitter  1693  to port  1628 . Optical splitter  1693  may also output the egress optical data signal onto secondary fiber  1638  connecting the optical splitter  1693  to port  1630 . 
     The operation of headend  1601  may be described by way of the processing of upstream optical data signals received at headend  1601  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal, may be an upstream optical data signal received on primary fiber  1637  or secondary fiber  1638  depending on the position of switch  1625 . The upstream optical data signal may be substantially the same as the egress optical data signal. 
     Because the multi-wavelength ingress optical data signal is routed to port  1622  of WDM  1619 , and is altered negligibly between connector  1626  and port  1622  or connector  1631  and port  1622 , depending on the position of switch  1625 , the multi-wavelength ingress optical data signal may be substantially the same as ingress optical data signal  1623 . The multi-wavelength ingress optical data signal may traverse  1626  and switch  1625 , before entering WDM  1619  via port  1622  if switch  1625  is connected to connector  1626 . The multi-wavelength ingress optical data signal may traverse connector  1631  and switch  1625 , before entering WDM  1619  via port  1622  if switch  1625  is connected to connector  1631 . WDM  1619  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from ingress optical data signal  1623 . WDM  1619  may transmit the one or more EPON optical data signals along GPON  1618  to PON connector  1602 . WDM  1619  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1632 ) out of port  1621  to OPA  1633 . 
     A gain of OPA  1633  may be based at least in part on a distance that the SONET/SDH egress optical data signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment on the SONET/SDH optical network connection. For instance, the gain of OPA  1633  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain of OPA  1633  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of the fiber of the SONET/SDH optical network connection). 10 GbE UP  1632  may be amplified by OPA  1633 , and OPA  1633  may output 10 GbE UP  1634  to DCM  1635 . 
     In some embodiments, DCM  1635  may be configured to balance positive and/or negative dispersion that may be introduced to a SONET/SDH egress optical data signal that may exit headend  1601  from 20×10 GbE UP  1604 . The SONET/SDH egress optical data signal may be an upstream signal from a field hub or outside plant destined for a MTC. For example, a customer premise may be connected to the field hub or outside plant and may send one or more packets via a SONET/SDH network to the field hub or outside plant which may in turn transmit the one or more packets using 10 GbE optical data signals to headend  1601 . The one or more packets may be destined for a company web server connected to the MTC via a backbone network. Because headend  1601  may be collocated in a STC that is connected to the MTC via an optical ring network, wherein the connection between the STC and MTC is a SONET/SDH optical network connection, DCM  1635  may be configured to compensate for positive and/or negative dispersion on the SONET/SDH optical network connection. That is DCM  1635  may be configured to reduce temporal broadening of the SONET/SDH ingress optical data signal or temporal contraction of the SONET/SDH ingress optical data signal. DCM  1635  may input 10 GbE UP  1634  and my output 10 GbE UP  1613  to WDM  1610 . 
     WDM  1610  may receive 10 GbE UP  1613  on port  1612 , and may output 10 GbE UP  1613  on port  1608  as a multi-wavelength upstream optical data signal (e.g., 10 GbE UP  1609 ). 10 GbE UP  1609  is substantially the same as 10 GbE UP  1613  because WDM  1610  may function as a circulator when 10 GbE UP  1613  is input to port  1612 . 10 GbE UP  1609  may be received by DWDM  1605 , and DWDM  1605  may demultiplex one or more 10 GbE optical data signals from 10 GbE UP  1609 . Because 10 GbE UP  1609  is a dispersion compensated amplified version of the multi-wavelength ingress optical data signal, DWDM  1605  may demultiplex the one or more optical data signals into individual optical data signals in accordance with the individual wavelengths of any 10 GbE optical data signals in the multi-wavelength ingress optical data signal. More specifically, 10 GbE UP  1609  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1605  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1604 . Each of the transponders of 20×10 GbE UP  1604  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1604  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIGS.  17 A and  17 B  depicts an access network diagram of an OCML headend comprising WDMs, a DWDM, optical amplifiers, and dispersion control modules (DCMs), in accordance with the disclosure.  FIG.  17 A  shows a schematic of an OCML headend according to at least one embodiment of the disclosure. As shown in  FIG.  17 A , headend  1701  is a smart integrated OCML headend, which is a circuit, comprising a DWDM (e.g., DWDM  1705 ), a first WDM (e.g., WDM  1717 ), a second WDM (e.g., WDM  1719 ), a third WDM (e.g., WDM  1723 ), a GPON/EPON connector (e.g., GPON/EPON  1724 ), a booster amplifier BOA (e.g., BOA  1716 ), an optical pre-amplifier (OPA) (e.g., OPA  1742 ), a variable optical attenuator (VOA) (e.g., VOA  1721 ), an optical switch  1726  to feed a primary optical fiber (e.g., Primary Fiber  1730 ) or secondary (backup) optical fiber (e.g., Secondary Fiber  1731 ), and a dispersion control module (DCM) (e.g., DCM  1708 ). DWDM  1705  may be similar in functionality to DWDM  106  and WDM  1717 , WDM  1719 , and WDM  1723  may be similar in functionality to WDM  108 . The disclosure provides a method of transporting multiple 10 GbE and GPON/EPON signals on the same optical fiber over extended links of up to 60 kms without a cable company having to put optical amplifiers between the cable&#39;s Master Terminal Center (MTC) facility and a field hub or outside plant. The MTC facility may be an inside plant facility where a cable company acquires and combines services to be offered to customers. The MTC facility provides these combined services to customers, by transmitting and receiving optical signals over a plurality of optical fibers to a field hub or outside plant which connects the plurality of optical fibers to a customer&#39;s premise. The OCML headend may be located in a secondary terminal center (STC) that connects the MTC facility to a field hub or outside plant housing a multiplexer-demultiplexer (MDM) (e.g., MDM  208  in  FIG.  2   ). 
     The EPON signals may operate with the same optical frequencies as GPON and time division multiple access (TDMA). The raw line data rate is 1.25 Gbits/s in both the downstream and upstream directions. EPON is fully compatible with other Ethernet standards, so no conversion or encapsulation is necessary when connecting to Ethernet-based networks on either end. The same Ethernet frame is used with a payload of up to 1518 bytes. EPON may not use a carrier sense multiple access (CSMA)/collision detection (CD) access method used in other versions of Ethernet. There is a 10-Gbit/s Ethernet version designated as 802.3ay. The line rate may be 10.3125 Gbits/s. The primary mode is 10 Gbits/s upstream as well as downstream. A variation uses 10 Gbits/s downstream and 1 Gbit/s upstream. The 10-Gbit/s versions use different optical wavelengths on the fiber, 1575 to 1591 nm downstream and 1260 to 1280 nm upstream so the 10-Gbit/s system can be wavelength multiplexed on the same fiber as a standard 1-Gbit/s system. 
     In one aspect, headend  1701  may comprise twenty 10 GbE downstream (DS) transponders (e.g., 20×10 GbE DS  1703 ) and twenty 10 GbE upstream (UP) transponders (e.g., 20×10 GbE UP  1704 ). 20×10 GbE DS  1703  may transmit downstream data over twenty 10 GbE wavelengths. 20×10 GbE UP  1704  may receive upstream data over 10 GbE wavelengths. 20×10 GbE DS  1703  may comprise the same elements and perform the same operations as 20×GbE DS  190 , and 20×10 GbE UP  1704  may comprise the same elements and perform the same operations as 20×GbE UP  188 . 
     The operation of headend  1701  may be described by way of the processing of downstream optical data signals transmitted from headend  1701  to a field hub or outside plant, and the processing of upstream optical data signals received from the field hub or outside plant. Each of the transponders of 20×10 GbE DS  1703  may receive a SONET/SDH optical data signal from a MTC and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE DS  1703  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE DS  1703  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1705  may receive the twenty corresponding second optical data signals as an input and output a multi-wavelength downstream optical data signal (e.g., 10 GbE DS  1707 ) comprising the twenty corresponding second optical data signals onto a fiber. The multi-wavelength downstream optical data signal 10 GbE DS  1707  may be a 10 GbE optical data signal. More specifically, DWDM  1705  may multiplex the twenty corresponding second optical data signals onto the fiber, wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength downstream optical data signal 10 GbE DS  1707 , may be input to DCM  1708 . 10 GbE DS  1707  may be input into DCM  1708  to compensate for dispersion that 10 GbE DS  1707  may experience after being amplified by BOA  1716  and multiplexed by WDM  1723 , with other optical data signals, that are downstream from the DCM. The amplified and multiplexed optical data signal may be referred to as an egress optical data signal, as it is the optical data signal that may be transmitted out of headend  1701  over a fiber connecting headend  1701  to a field hub or outside plant. In some embodiments, DCM  1708  may be configured to balance positive and/or negative dispersion that may be introduced to the egress optical data signal by the fiber. In some embodiments, DCM  1708  may be configured to compensate for positive (temporal broadening of the egress optical data signal) and/or negative (temporal contraction of the egress optical data signal) dispersion introduced by fiber that is 80 km or greater in length, to reduce the sensitivity or OSNR levels of a transceiver in a DWDM located at a field hub or outside plant. More specifically, DCM  1708  may be configured to reduce the sensitivity or OSNR level requirement in a photodetector or fiber-optic sensor in the transceiver, which may drastically reduce the cost of the transceivers used in the DWDM located at the field hub or outside plant. DCM  1708  may output a dispersion controlled version of 10 GbE DS  1707  as 10 GbE DS  1710 . 
     WDM  1717  may be a three port circulator, that receives multi-wavelength downstream optical data signal 10 GbE DS  1710  on port  1711 , and outputs multi-wavelength downstream optical data signal 10 GbE DS  1710 , on port  1714  as multi-wavelength downstream optical data signal 10 GbE DS  1715  to BOA  1716 . In some embodiments, Headend  1701  may not include DCM  1708 . 
     BOA  1716  may have a gain that is based at least in part on a distance that a downstream signal has to travel. For example, the gain may be a function of a fiber attenuation coefficient α, which is a measure of the intensity of the attenuation of a beam of light as it traverses a length of an optical fiber segment. The unit of measurement of the fiber attenuation coefficient is decibels (dB) per km (dB/km). For instance, BOA  1716  may be adjusted based at least in part on the attenuation coefficient and length of fiber that the egress optical data signal will travel. More specifically, the gain BOA  1716  may be G=e (2αL) , where α is the fiber attenuation coefficient, as explained above, and L is the length of the fiber (e.g., the length of primary fiber  1730  and/or the length of secondary fiber  1731 ). Multi-wavelength downstream optical data signal 10 GbE DS  1715  may be amplified by BOA  1716 , and BOA  1716  may output multi-wavelength downstream optical data signal 10 GbE DS  1717  to port  1718  of WDM  1719 . WDM  1719  outputs a multi-wavelength downstream optical data signal (e.g., multi-wavelength downstream optical data signal 10 GbE DS  1740 ) from port  1720 , which may be substantially the same as multi-wavelength downstream optical data signal 10 GbE DS  1717 . Multi-wavelength downstream optical data signal 10 GbE DS  1740  may be input to variable optical amplifier (VOA)  1721 . 
     VOA  1721  may be used to reduce the power levels of multi-wavelength downstream optical data signal 10 GbE DS  1740 . The power reduction may be done by absorption, reflection, diffusion, scattering, deflection, diffraction, and dispersion, of multi-wavelength downstream optical data signal 10 GbE DS  1740 . VOA  1721  typically have a working wavelength range in which they absorb all light energy equally. In some embodiments VOA  1721  utilize a length of high-loss optical fiber, that operates upon its input optical signal power level in such a way that its output signal power level is less than the input level. For example, multi-wavelength downstream optical data signal 10 GbE DS  1740  may have an input power level to VOA  1721  that may be greater than the output power level of multi-wavelength downstream optical data signal 10 GbE DS  1739 . 
     The variability of the output power level of VOA  1721  may be achieved using a fiber coupler, where some of the power is not sent to the port that outputs, but to another port. Another possibility is to exploit variable coupling losses, which are influenced by variable positioning of a fiber end. For example, the transverse position of the output fiber or the width of an air gap between two fibers may be varied, obtaining a variable loss without a strong wavelength dependence. This principle may be used for single-mode fibers. VOA  1721  may be based on some piece of doped fiber, exhibiting absorption within a certain wavelength range. 
     WDM  1723  may multiplex multi-wavelength downstream optical data signal 10 GbE DS  1739  and one or more EPON, and/or GPON optical data signals. The EPON and/or GPON optical data signals may be received on a GPON/EPON connector (e.g., GPON/EPON  1724 ) from PON port  1702 . The resulting multiplexed optical data signal may be referred to as egress optical data signal  1735 . 
       FIG.  17 B  depicts an access network diagram of a multiplexer-demultiplexer (MDM), in accordance with the disclosure. Egress optical data signal  1735  may be output by WDM  1723  and optical switch  1726  may switch egress optical data signal  1735  onto connector  1727  or connector  1734  depending on the position of switch  1726 . In some embodiments, connector  1727  may be a primary connector and connector  1734  may be a secondary connector or a backup connector. Wavelength monitoring connector  1728  may connect connector  1727  to a first port of wavelength-monitoring ports  1744 , and wavelength monitoring connector  1733  may connect connector  1734  to a second port of wavelength-monitoring ports  1744 . Wavelength-monitoring ports  1744  may monitor the wavelengths in egress optical data signal  1735  via connector  1727  or connector  1734  depending on the position of switch  1726 . Egress optical data signal  1735  may exit headend  1701  via connector  1727  connected to primary fiber  1730 , and may be received on a first connector in the field hub or outside plant. Egress optical data signal  1735  may exit headend  1701  via connector  1734  connected to secondary fiber  1731 , and may be received on a second connector in the field hub or outside plant. The field hub or outside plant may include a MDM with the first connector and the second connector. 
     Egress optical data signal  1735  may be received at optical splitter  1793  as an ingress optical data signal. Optical splitter  1793  may also be referred to as a beam splitter, and may comprise one or more quartz substrates of an integrated waveguide optical power distribution device. Optical splitter  1793  may be a passive optical network device. It may be an optical fiber tandem deice comprising one or more input terminals and one or more output terminals. Optical splitter  1793  may be Fused Biconical Taper (FBT) splitter or Planar Lightwave Circuit (PLC) splitter. Optical splitter  1793  may be a balanced splitter wherein optical splitter  1793  comprises 2 input fibers and one or more output fibers over which the ingress optical data signal may be spread proportionally. In some embodiments, the ingress optical data signal may not be spread proportionally across the output fibers of optical splitter  1793 . In some embodiments, optical splitter  1793  may comprise 2 input fibers and 2 output fibers. A first input fiber of optical splitter  1793  may be connected to primary fiber  1730  and a second input fiber of optical splitter  1793  may be connected to secondary fiber  1731 . 
     A first output fiber of optical splitter  1793  may be connected to a filter (e.g., C-band block  1792 ) that filters out packets of light, in the ingress optical data signal, with wavelengths between 1530 nm and 1565 nm. This range of wavelengths may coincide with a C-band of wavelengths. In some other embodiments, the filter may filter out packets of light with wavelengths not inclusive of the wavelengths between 1260 nm and 1520 nm and not inclusive of wavelengths between 1570 nm and 1660 nm. The packets of light with wavelengths inclusive of the wavelengths between 1260 nm and 1520 nm and inclusive of wavelengths between 1570 nm and 1660 nm, may correspond to the wavelengths of the packets of light carrying the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1724 . More specifically, optical splitter  1793 , may receive one or more downstream EPON and/or GPON optical data signals  1760 , in the ingress optical data signal, that corresponds to the one or more EPON and/or GPON optical data signals transmitted along GPON/EPON  1724 . In some embodiments, the one or more downstream EPON and/or GPON optical data signals  1760  may have the same wavelength as GPON DS  1703 . Optical splitter  1793  may output the one or more downstream EPON and/or GPON optical data signals  1760 , received in the ingress optical data signal, to C-band block  1792 . 
     C-band block  1792  may output one or more downstream EPON and/or GPON optical data signals  1797  corresponding to the one or more downstream EPON and/or GPON optical data signals  1760  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. The C-band block  1792  may transmit the one or more downstream EPON and/or GPON optical data signals  1797  to an express port (not shown in  FIG.  17   ) collocated with, or attached to MDM  1791 . In some embodiments, the express port may be located within the MDM  1791 . 
     A second output fiber of optical splitter  1793  may be connected to COP  1794 . COP  1794  may be a PON device that monitors the coupled optical power between Optical Splitter  1793  and DWDM  1796 . In some embodiments, the coupled optical power may be a percentage value. For instance, the coupled optical power may be 1%. Optical splitter  1793 , may receive one or more downstream 10 GbE optical data signals, in the ingress optical data signal, that corresponds to 10 GbE DS  1703 . In some embodiments, the one or more downstream 10 GbE optical data signals may have the same wavelength as 10 GbE  808 . Optical splitter  1793  may output the one or more downstream 10 GbE optical data signals  1763 , received in the ingress optical data signal, to COP  1794 . COP  1794  may output a first percentage of the one or more downstream 10 GbE optical data signals  1763  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1795 ). The first percentage may be a percentage of the one or more downstream 10 GbE optical data signals  1763  tested by the 10 GbE upstream and downstream test ports. The first percentage of the one or more downstream 10 GbE optical data signals  1763  may be a monitoring signal used by a spectrum analyzer to measure optical power levels of a specific wavelength. The first percentage of the one or more downstream 10 GbE optical data signals  1763  may also be used by the spectrum analyzer to analyze certain characteristics of the wavelengths of the first percentage of the one or more downstream 10 GbE optical data signals  1763 . COP  1794  may output a second percentage of the one or more downstream 10 GbE optical data signals  1765  to DWDM  1796 . 
     Because the one or more downstream 10 GbE optical data signals  1765  may be a multi-wavelength downstream optical data signal DWDM  1796  may demultiplex the one or more downstream 10 GbE optical data signals  1765  into individual optical data signals in accordance with the individual wavelengths of the one or more downstream 10 GbE optical data signals  1765 . More specifically, the one or more downstream 10 GbE optical data signals  1765  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1796  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE DS  1797 . Each of the transponders of 20×10 GbE DS  1797  may be in a RPD (not shown) and may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. In some embodiments, the RPD may be similar in functionality to Remote PHY Node  207 . The RPD may convert the SONET/SDH optical data signals into an electrical signal that may be transmitted over one or more coaxial cables. MDM  1791  may be similar in functionality to MDM  208  and may be connected to the RPD in a way similar to the connection between MDM  208  and Remote PHY Node  207 . 
     The operation of MDM  1791  may be further described by way of the processing of an upstream optical data signal transmitted to headend  1701 . Each of the transponders of 20×10 GbE UP  1799  may receive a SONET/SDH optical data signal and each of the transponders may convert the SONET/SDH optical data signal into an electrical signal. Each of the transponders of 20×10 GbE UP  1799  may receive the SONET/SDH optical data signal from the RPD. The RPD may also convert one or more electrical signals into the SONET/SDH optical data signal. 
     More specifically, a first transceiver in the transponder may convert the SONET/SDH optical data signal into an electrical signal. A second transceiver may then convert the electrical signal into a second optical data signal, wherein the second optical data signal comprises one or more packets of light each of which may have a distinct wavelength. Because the one or more packets of light each have a distinct wavelength, the second optical data signal may be said to have this distinct wavelength. Thus, the twenty transponders in 20×10 GbE UP  1799  may each receive a SONET/SDH optical data signal, and each of the twenty transponders may convert the received SONET/SDH optical data signal into a corresponding second optical data signal, wherein each of the corresponding second optical data signals has a unique wavelength. That is, the wavelength of each of the corresponding second optical data signals is distinguishable from the wavelength of any of the other corresponding second optical data signals. Thus 20×10 GbE UP  1799  may generate twenty corresponding second optical data signals each of which has a unique wavelength. 
     DWDM  1796  may receive twenty corresponding second optical data signals as an input and output a multi-wavelength upstream optical data signal (e.g., multi-wavelength upstream optical data signal  1764 ) comprising the twenty corresponding second optical data signals. The multi-wavelength upstream optical data signal  1764  may be a 10 GbE optical data signal. More specifically, DWDM  1796  may multiplex the twenty corresponding second optical data signals onto the fiber connecting DWDM  1796  and COP  1794 , wherein the twenty multiplexed corresponding second optical data signals compose the multi-wavelength downstream optical data signal. The multi-wavelength optical data signal may have a wavelength comprising the twenty wavelengths of the twenty corresponding second optical data signals. 
     The multi-wavelength upstream optical data signal  1764 , may be input to COP  1794 . COP  1794  may output a first percentage of the multi-wavelength upstream optical data signal  1764  to 10 GbE upstream and downstream test ports (e.g., 10 GbE UP &amp; DS Test Ports  1795 ). The first percentage may be a percentage of the multi-wavelength upstream optical data signal  1764  tested by the 10 GbE upstream and downstream test ports. The first percentage of the multi-wavelength upstream optical data signal  1764  may be a monitoring signal used by a spectrum analyzer to measure optical power levels of a specific wavelength in the multi-wavelength upstream optical data signal  1764 . The first percentage of the multi-wavelength upstream optical data signal  1764  may also be used by the spectrum analyzer to analyze certain characteristics of the wavelengths of the first percentage of the multi-wavelength upstream optical data signal  1764 . COP  1794  may output a second percentage of the multi-wavelength upstream optical data signal  1764  to optical splitter  1793  as the multi-wavelength upstream optical data signal  1762 . 
     C-band block  1792  may receive one or more upstream EPON and/or GPON optical data signals  1766  from an express port (not shown in  FIG.  17   ) collocated with, or attached to MDM  1791 . In some embodiments, the express port may be located within the MDM  1791 . C-band block  1792  may filter out packets of light, in the one or more upstream EPON and/or GPON optical data signals  1766 , with wavelengths between 1530 nm and 1565 nm. Thus C-band block  1792  may output one or more upstream EPON and/or GPON optical data signals  1761  with wavelengths between 1260 nm and 1520 nm and wavelengths between 1570 nm and 1660 nm. 
     Optical splitter  1793  may receive one or more upstream EPON and/or GPON optical data signals  1761 , and may also receive the multi-wavelength upstream optical data signal  1762 , and may multiplex the multi-wavelength one or more upstream EPON and/or GPON optical data signals  1761  with the multi-wavelength upstream optical data signal  1762 . Optical splitter  1793  outputs an egress optical data signal, which may be a multi-wavelength optical data signal comprising 10 GbE, GPON/EPON optical data signals corresponding to the multiplexed multi-wavelength one or more upstream EPON and/or GPON optical data signals  1761  and multi-wavelength upstream optical data signal  1762 . Optical splitter  1793  may output the egress optical data signal onto primary fiber  1730  connecting the optical splitter  1793  to port  1729 . Optical splitter  1793  may also output the egress optical data signal onto secondary fiber  1731  connecting the optical splitter  1793  to port  1732 . 
     The operation of headend  1701  may be described by way of the processing of upstream optical data signals received at headend  1701  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal or a 10GEPN.XGPON may be an upstream optical data signal received on primary fiber  1730  or secondary fiber  1731  depending on the position of switch  1726 . The upstream optical data signal may be substantially the same as the egress optical data signal. 
     Multi-wavelength ingress optical data signal  1736  may traverse connector  1727  and switch  1726 , before entering WDM  1723  via port  1737  if switch  1726  is connected to connector  1727 . Multi-wavelength ingress optical data signal  1736  may traverse connector  1734  and switch  1726 , before entering WDM  1723  via port  1737  if switch  1726  is connected to connector  1727 . WDM  1723  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from multi-wavelength ingress optical data signal  1736 . WDM  1723  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1724  to PON connector  1702  via port  1725 . WDM  1723  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1741 ) out of port  1738  to OPA  1742 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1741  may be received by OPA  1742 . The one or more optical data signals 10 GbE UP  1741  may comprise 10 GbE optical data signals. A gain associated OPA  1742  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1716 . The one or more optical data signals 10 GbE UP  1741  may be amplified by OPA  1742 , and OPA  1742  may output multi-wavelength upstream optical data signal  1743  to WDM  1713 . 
     WDM  1717  may receive the multi-wavelength upstream optical data signal  1743  on port  1712 , and may output one or more optical data signals 10 GbE UP  1709  to DCM  1708 . DCM  1708  may perform one or more operations on one or more optical data signals 10 GbE UP  1709  to compensate for any dispersion that may have been introduced by circuit components (e.g., WDM  1713 , OPA  1742 , or WDM  1723 ) or imperfections or issues with an optical fiber (e.g., primary fiber  1730  or secondary fiber  1731 ). DCM  1708  may output one or more optical data signals 10 GbE UP  1706  to DWDM  1705 . The one or more optical data signals 10 GbE UP  1709  are substantially the same as multi-wavelength upstream optical data signal  1743 . WDM  1717  may function as a circulator when receiving multi-wavelength upstream optical data signal  1743  on port  1712 . The one or more optical data signals 10 GbE UP  1706  may be received by DWDM  1705 . 
     The one or more optical data signals 10 GbE UP  1706  may comprise 10 GbE optical data signals. DWDM  1705  may demultiplex the one or more optical data signals 10 GbE UP  1706  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1706 . More specifically, the one or more optical data signals 10 GbE UP  1706  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1705  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1704 . Each of the transponders of 20×10 GbE UP  1704  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1704  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
     The operation of headend  1701  may be described by way of the processing of upstream optical data signals received at headend  1701  from a field hub or outside plant. For instance, a multi-wavelength ingress optical data signal, comprising one or more of a 10 GbE optical data signal, EPON optical data signal, and/or GPON optical data signal or a 10GEPN.XGPON may be an upstream optical data signal received on primary fiber  1730  or secondary fiber  1731  depending on the position of switch  1726 . 
     Multi-wavelength ingress optical data signal  1736  may traverse connector  1727  and switch  1726 , before entering WDM  1723  via port  1737  if switch  1726  is connected to connector  1727 . Multi-wavelength ingress optical data signal  1736  may traverse connector  1734  and switch  1726 , before entering WDM  1723  via port  1737  if switch  1726  is connected to connector  1727 . WDM  1723  may demultiplex one or more 10 GbE optical data signals, EPON optical data signals, and/or GPON optical data signals from multi-wavelength ingress optical data signal  1736 . WDM  1723  may transmit the one or more EPON and/or GPON optical data signals along GPON/EPON  1724  to PON connector  1702  via port  1725 . WDM  1723  may transmit the one or more 10 GbE optical data signals (e.g., 10 GbE UP  1741 ) out of port  1738  to OPA  1742 . 
     The one or more 10 GbE optical data signals 10 GbE UP  1741  may be received by OPA  1742 . The one or more optical data signals 10 GbE UP  1741  may comprise 10 GbE optical data signals. A gain associated OPA  1742  may be based at least in part on a distance that 10 GbE optical data signals have to travel, similar to that of BOA  1716 . The one or more optical data signals 10 GbE UP  1741  may be amplified by OPA  1742 , and OPA  1742  may output multi-wavelength upstream optical data signal  1743  to WDM  1717 . 
     WDM  1717  may receive the multi-wavelength upstream optical data signal  1743  on port  1712 , and may output one or more optical data signals 10 GbE UP  1709  to DCM  1708 . DCM  1708  may perform one or more operations on one or more optical data signals 10 GbE UP  1709  to compensate for any dispersion that may have been introduced by circuit components (e.g., WDM  1717 , OPA  1742 , or WDM  1723 ) or imperfections or issues with an optical fiber (e.g., primary fiber  1730  or secondary fiber  1731 ). DCM  1708  may output one or more optical data signals 10 GbE UP  1706  to DWDM  1705 . The one or more optical data signals 10 GbE UP  1709  are substantially the same as multi-wavelength upstream optical data signal  1743 . WDM  1717  may function as a circulator when receiving multi-wavelength upstream optical data signal  1743  on port  1712 . The one or more optical data signals 10 GbE UP  1706  may be received by DWDM  1705 . 
     The one or more optical data signals 10 GbE UP  1706  may comprise 10 GbE optical data signals. DWDM  1705  may demultiplex the one or more optical data signals 10 GbE UP  1706  into individual optical data signals in accordance with the individual wavelengths of the one or more optical data signals 10 GbE UP  1706 . More specifically, the one or more optical data signals 10 GbE UP  1706  may be demultiplexed into twenty 10 GbE optical data signals, each of which may have a unique wavelength. DWDM  1705  may output each of the twenty 10 GbE optical data signals to each of the transponders of 20×10 GbE UP  1704 . Each of the transponders of 20×10 GbE UP  1704  may convert a received corresponding 10 GbE optical data signal, of the 10 GbE optical data signals, into a corresponding electrical signal. More specifically, a first transceiver in each of the transponders may convert each of the twenty 10 GbE optical data signals into the corresponding electrical signal. Each of the transponders may also comprise a second transceiver that may convert the corresponding electrical signal into a SONET/SDH optical data signal with a corresponding SONET/SDH optical data signal wavelength. In some embodiments, each of the twenty corresponding SONET/SDH optical data signals may have the same wavelength. In other embodiments, each of the twenty corresponding SONET/SDH optical data signals may have unique wavelengths. The twenty transponders of 20×10 GbE UP  1704  may transmit the twenty SONET/SDH optical data signals to the MTC on the SONET/SDH optical network connection. 
       FIG.  18    depicts an access network diagram of an OCML headend and outside plant, in accordance with the disclosure. At block  1802  the OCML headend may receive one or more first optical data signals from a network. At block  1804  the OCML headend may combine the one or more first optical data signals. At block  1806  the OCML headend may generate a second optical data signal based at least in part on applying the combined one or more first optical data signals to a dispersion compensation module (DCM). At block  1808  the OCML headend may generate a third optical data signal based at least in part on applying the second optical data signal to an optical amplifier. At block  1810  the OCML headend may combine the third optical data signal with one or more passive optical network (PON) signals into a fourth optical data signal. At block  1812  the OCML headend may transmit the fourth optical data signal to a field hub. 
       FIG.  18    may cover the operation of the OCML headend in  FIGS.  1 ,  10 ,  11 ,  14 ,  16 , and  17    in the downstream. 
       FIG.  19    depicts a process of transmitting optical signals with the OCML headend, in accordance with the disclosure. At block  1902  the OCML headend may receive one or more first optical data signals from a network. At block  1904  the OCML headend may generate a second optical data signal by combining the one or more first optical data signals. At block  1906  the OCML headend may generate a third optical data signal by combining the second optical data signal with one or more passive optical network (PON) signals. At block  1908  the headend may transmit the fourth optical data signal to a field hub. The flowchart in  FIG.  19    may cover the operation of the terminal in  FIGS.  3 ,  5 ,  6 ,  12 , and  15    in the downstream. 
       FIG.  20    depicts a process of transmitting optical signals with the OCML headend, in accordance with the disclosure. At block  2002  the OCML headend may receive one or more first optical data signals from a network. At block  2004  the OCML headend may combine the one or more first optical data signals. At block  2006  the OCML headend may generate a second optical data signal based at least in part on applying the combined one or more first optical data signals to a dispersion compensation module (DCM). At block  2008  the OCML headend may generate a third optical data signal based at least in part on applying the second optical data signal to an optical amplifier. At block  2010  the OCML headend may generate a fourth optical data signal based at least in part on applying the third optical data signal to a variable optical attenuator. At block  2012  the OCML headend may combine the fourth optical data signal with one or more passive optical network (PON) signals into a fifth optical data signal. At block  2014  the OCML terminal may transmit the fifth optical data signal to a field hub. The flowchart in  FIG.  20    may cover the operation of  FIG.  13    in the downstream.