Abstract:
A data network for a multiple dwelling unit (MDU) enables efficient use of a MoCA (Multimedia over Coax Alliance) system. The data network includes a distribution point unit (DPU) connected to an access network, a plurality of modems in the MDU, a plurality of coaxial cables extending through the MDU between the DPU and the plurality of modems, and at least one network expander present between the DPU and a subset of the plurality of modems. The network expander can be a repeater that retransmits received signals, wherein the DPU, the plurality of modems, and the network expander exchange data via the plurality of coaxial cables using MoCA protocols.

Description:
CLAIM OF PRIORITY 
       [0001]    This Application claims priority under 35 U.S.C. §119(e) from earlier filed U.S. Provisional Application Ser. No. 62/301,080, filed Feb. 29, 2016, which is hereby incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to the field of data networking, particularly a system for providing individual units in a multiple dwelling unit (MDU) with network access over coaxial cable using MoCA (Multimedia over Coax Alliance) technology. 
       BACKGROUND 
       [0003]    Many uses of the internet, such as file transmission, video streaming, and videoconferencing, are best experienced when data can be transferred at high rates. Accordingly, users generally prefer high-bandwidth internet connections. High-bandwidth internet connections can be provided to some buildings, such as single family homes, relatively easily by connecting the building to a high-speed network with a single “last mile” connection. 
         [0004]    However, providing high-bandwidth connections can be more challenging when a building is a multiple dwelling unit (MDU) with multiple units that each need their own separate network connection. While a last mile connection can be provided to the MDU, network architecture must be put in place that splits the single network connection among each unit. Accordingly, cable and other telecommunications companies have been developing systems for providing high-bandwidth network connections to customers in MDUs, including providing network access over loops that may be longer than 250 meters. In particular, many telecommunications companies are looking for solutions that can provide network access to MDU customers at speeds of 1 Gbps (Gigabit per second) or greater, at low power and low cost, and with flexible deployment options. 
         [0005]    It is generally not feasible in most existing MDUs to install new high-speed network cables, like fiber optic cables or CAT5 cables, throughout the building to provide high-speed internet access to each unit. Instead, some solutions have attempted to provide network access over cables that are already present in the MDU, such as copper phone lines or coaxial cables originally installed for television. 
         [0006]    For example, some solutions have used digital subscriber line (DSL) protocols such as G.fast to provide MDUs with network access over phone lines that already extend to each unit in the MDU. However, while speeds over G.fast can be relatively fast, they can be slower than some users would prefer. For example, in some implementations a G.fast network that splits an aggregate network connection with 2.5 Gbps downstream speeds and 1.25 Gbps upstream speeds to an MDU between sixteen units can result in a maximum aggregate data rate of only 700 Mbps per unit. Additionally, in some G.fast implementations network speeds can decrease substantially as the cable to the unit increases. For example, while a unit less than 100 meters away from an MDU&#39;s connection to an access network may be able to reach 1 Gbps aggregate data rates over G.fast, another unit in the same building that is 500 meters away from the access network connection may only reach 100 Mbps aggregate data rates due to the longer distance. Due to these issues with G.fast, telecommunications companies have been looking for solutions that use coaxial cable as an alternative and/or a supplement to G.fast in MDU environments. 
         [0007]    What is needed is a system for providing network access to units of an MDU over coaxial cables that may already be present in an MDU. Such a system should provide each unit with comparable high-bandwidth network access regardless of their distance from the MDU&#39;s initial connection to an access network, and in some cases also allow cable or satellite television signals to be passed over the same coaxial cable. 
       SUMMARY 
       [0008]    The present disclosure provides a Multimedia over Coax Alliance (MoCA) system, the system comprising at least one network expander for distributing at least one signal channel, at least one distribution point unit (DPU) distributing the at least one signal channel to and from the network expander, and one or more modems receiving the at least one signal channel, wherein the network expander is connected between the DPU and a set of the modems and retransmits received signals using MoCA protocols. 
         [0009]    The present disclosure also provides Multimedia over Coax Alliance (MoCA) system, the system comprising at least one network expander for distributing at least one signal channel by retransmitting received signals using MoCA protocols. 
         [0010]    The present disclosure also provides a data network for a multiple dwelling unit (MDU), the data network comprising a distribution point unit (DPU) comprising one or more coaxial cable ports and a network cable interface connected to an access network, a plurality of modems in the MDU, a plurality of coaxial cables extending through the MDU from the one or more coaxial cable ports of the DPU to the plurality of modems, and at least one network expander present between the DPU and a subset of the plurality of modems, the network expander being a repeater that retransmits received signals, wherein the DPU, the plurality of modems, and the at least one network expander exchange data via the plurality of coaxial cables using MoCA (Multimedia over Coax Alliance) protocols. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Further details of the present invention are explained with the help of the attached drawings in which: 
           [0012]      FIG. 1  depicts an exemplary embodiment of a multiple dwelling unit (MDU) network. 
           [0013]      FIG. 2  depicts an exemplary embodiment of an MDU network in which two distribution point units (DPUs) are daisy chained together. 
           [0014]      FIG. 3  depicts an exemplary embodiment of a single-band DPU. 
           [0015]      FIG. 4  depicts an exemplary embodiment of a dual-band DPU. 
           [0016]      FIG. 5  depicts an exemplary embodiment of a modem. 
           [0017]      FIG. 6  depicts an exemplary embodiment of a pluggable transceiver modem. 
           [0018]      FIG. 7  depicts an exemplary embodiment in which a power inserter and a network expander are present between a DPU  106  and modems. 
           [0019]      FIG. 8  depicts a non-limiting example of a single-band MDU network in use. 
           [0020]      FIG. 9A  depicts a graph of aggregate data rates measured during a test at different distances between a single-band DPU and a single-band modem. 
           [0021]      FIG. 9B  depicts a graph of aggregate data rates measured during a test at different distances between a single-band network expander and a single-band modem. 
           [0022]      FIG. 9C  depicts a graph of aggregate data rates measured during a test at different distances between a single-band DPU and a single-band modem when one single-band DPU is present between them. 
           [0023]      FIG. 10  depicts a non-limiting example of a dual-band MDU network in use. 
           [0024]      FIG. 11A  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band DPU and a dual-band modem. 
           [0025]      FIG. 11B  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band network expander and a dual-band modem. 
           [0026]      FIG. 11C  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band DPU and a dual-band modem when one dual-band DPU is present between them. 
           [0027]      FIG. 12A  depicts an embodiment in which a television source and a DPU both feed into a combiner linked to a shared coaxial cable. 
           [0028]      FIG. 12B  depicts an embodiment in which a DPU feeds into a splitter that can lead to a plurality of different combiners linked to a television source. 
           [0029]      FIG. 12C  depicts an embodiment in which a network expander extends the length of a link of coaxial cable between a DPU and a splitter. 
           [0030]      FIG. 12D  depicts an embodiment in which a network expander is connected to a splitter to expand the number of modems that can be connected to a DPU. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]      FIG. 1  depicts an exemplary embodiment of a multiple dwelling unit (MDU) network  100 . An MDU network  100  can be present in an MDU such as an apartment building, condominium building, dormitory, retirement home, or any other building or complex that that has occupants in a plurality of different units. An MDU network  100  can be used to provide each unit in the MDU with its own connection to an access network  102 , through which devices in the units can connect to a data network such as the Internet. By way of a non-limiting example, an access network  102  can be a passive optical network (PON), such as a Gigabit-capable passive optical network (GPON) or 10-Gigabit-capable passive optical network (XGPON). While network architecture and network components are described herein with respect to MDUs, they can also be used in other types of buildings or complexes that have multiple units that may desire separate network access, such as hotels or office buildings. 
         [0032]    The MDU network  100  can comprise a plurality of lines of coaxial cable  104 , one or more distribution point units (DPUs)  106 , and one or more modems  108 . The DPU  106  can be an interface between an access network  102  and the rest of the MDU network  100 . By way of a non-limiting example, in some embodiments a connection to the access network  102  can enter an MDU at a basement or other area that is accessible to installers or maintenance workers, and the DPU  106  can be located at that area of the MDU. 
         [0033]    The DPU  106  can be connected to modems  108  located in one or more locations in the MDU via coaxial cables  104 . By way of a non-limiting example, coaxial cables  104  can extend into each of a plurality of different apartment units in an apartment building, such that modems  108  in those apartment units can be linked to the DPU  106  via the coaxial cable  104 . In some embodiments a network of coaxial cable  104  can comprise splitters  110  that split one line of coaxial cable  104  into a plurality of lines of coaxial cable  104  that extend to different locations in the MDU. 
         [0034]    In some embodiments the coaxial cables  104  in an MDU network  100  can be previously existing coaxial cabling that was already present in an MDU. By way of a non-limiting example an apartment building can have been built with a network of coaxial cable  104  that extends into each apartment unit in the building, such as coaxial cabling originally installed to provide the apartments with access to cable or satellite television. Accordingly, an MDU network  100  can re-use existing coaxial cable  104  in an MDU without the need to retrofit the MDU with new network cables. In other embodiments, an MDU can be newly built or retrofitted with coaxial cable  104  for the MDU network  100 . 
         [0035]    The MDU network  100 , including components such as the DPUs  106  and modems  108 , can be configured to transmit data over the coaxial cables  104  using a MoCA (Multimedia over Coax Alliance) protocol. Data can be transmitted over coaxial cable  104  using MoCA at speeds up to, or exceeding, 1 Gbps. In alternate embodiments, elements of the MDU network  100  can transmit data using MoCA wirelessly or over a different type of physical connection, such as fiber optic cables. Using MoCA, the MDU network  100  can be a fully meshed point to point network in which the network nodes, such as the DPUs  106  and modems  108 , are bi-directionally connected. 
         [0036]    MoCA transmits data over a plurality of RF (radio frequency) channels that span a range of frequencies, with each channel being divided into a plurality of sub-bands distinguished using orthogonal frequency-division multiplexing (OFDM). By way of a non-limiting example, MoCA 2.0 uses RF channels within a frequency range from 500 MHz to 1650 MHz. 
         [0037]    Elements of an MDU network  100 , including DPUs  106 , modems  108 , and other equipment such as network expanders  704  discussed below, can be single-band or dual-band bonded MoCA devices. Single-band elements can transmit data using channels in one range of RF frequencies, while dual-band elements can transmit data simultaneously using channels in two different frequency ranges. The frequency ranges used for single-band and/or dual-band embodiments can be link aggregated over multiple RF channels. By way of a non-limiting example, in some embodiments dual-band devices can aggregate across four separate OFDM blocks, while other embodiments can be aggregated across more or fewer OFDM blocks. In some embodiments single-band and dual-band equipment can be compatible with one another in the same MDU network  100 . By way of a non-limiting example, a dual-band DPU  106  can exchange data with a single-band modem by using channels in the band known to the modem  108 . 
         [0038]    In some embodiments the DPUs  106  and modems  108  in an MDU network  100  can be configured to use frequencies in the MoCA range to transmit data that do not conflict with frequencies used to transmit cable television to units over the same coaxial cable  104 . By way of a non-limiting example, the DPUs  106  and modems  108  can transmit data using frequencies between 500 MHz and 850 MHz, while a television provider can transmit television signals over the same coaxial cable  104  using frequencies between 950 MHz and 2150 MHz. By way of another non-limiting example, the DPUs  106  and modems  108  can transmit data using frequencies between 800 MHz and 1650 MHz, while a television provider can transmit television signals over the same coaxial cable  104  using frequencies between 54 MHz and 700 MHz. As such, the MDU network  100  can allow data and television transmissions to coexist on the same coaxial cable  104 . 
         [0039]    A DPU  106  can comprise one or more coaxial ports  112  and one or more network cable interfaces  114 . A coaxial port  112  can receive a coaxial cable  104 , in order to provide a link for upstream and/or downstream data connections with other devices in the MDU network  100 . As described above, a DPU  106  can use MoCA to transmit and receive data via coaxial cable  104  through its coaxial ports  112 . 
         [0040]    A network cable interface  114  can be a port at the DPU  106  that can receive a network cable  116 , such as a fiber optic cable or CAT5 cable. A network cable  116  coupled with a network cable interface  114  can provide a link for upstream and/or downstream data connections with other devices and/or networks. 
         [0041]    In some embodiments a network cable interface  114  can be a pluggable transceiver that can be removably inserted into the DPU  106 . By way of a non-limiting example, in some embodiments a network cable interface  114  can be a small form-factor pluggable (SFP) As such, different pluggable transceivers can be swapped out to change or upgrade a DPU&#39;s network cable interface  114 , or to change the type of network cable  116  the network cable interface  114  accepts. In alternate embodiments a network cable interface  114  can be a network cable port permanently integrated into the DPU  106 . 
         [0042]    At least one network cable interface  114  in a DPU  106  can provide a direct or indirect link to an access network  102  via a network cable  116 . In some embodiments or situations a network cable  116  connected to a network cable interface  114  can be a fiber optic cable linked to a PON or other access network  102 . In other embodiments or situations a network cable  116  connected to a network cable interface  114  can be an Ethernet cable linked to another network element that is linked to the access network  102 , such that the DPU  106  can have indirect network access to the access network  102  via the Ethernet cable and intermediate network elements. 
         [0043]    As shown in  FIG. 2 , in embodiments in which at least one DPU  106  has two network cable interfaces  114 , network cables  116  can be connected between the network cable interfaces  114  of different DPUs  106  to daisy chain the DPUs  106  together. By way of a non-limiting example a network cable  116 , such as a fiber optic cable, can connect a first DPU  106  to an access network  102  through one of its network cable interfaces  114 . Another network cable  116 , such as a CAT5 Ethernet cable, can then connect a second network cable interface  114  at the first DPU  106  to a network cable interface  114  at a second DPU  106 . As such, the second DPU  106  can reach the access network  102  via the network cable  116  connected to the first DPU  106 . Similarly, additional DPUs  106  can be connected to earlier DPUs  106  in the chain as desired via the network cable interfaces  114 . 
         [0044]      FIG. 3  depicts an exemplary embodiment of a single-band DPU  106 . A single-band DPU  106  can comprise one network cable interface  114  and a plurality of coaxial ports  112 . By way of a non-limiting example the single-band DPU  106  shown in  FIG. 3  has four coaxial ports  112 , however in alternate embodiments the DPU  106  can have any other number of coaxial ports  112 . The network cable interface  114  can be linked to the plurality of coaxial ports  112  through a chain comprising a traffic manager  302 , a network controller  304 , an RF front-end (RFFE)  306 , and a junction  308 . 
         [0045]    The traffic manager  302  can process network traffic to enforce class of service (CoS) and quality of service (QoS) policies. CoS policies can prioritize network traffic for subscribers that have subscribed to higher tiers of network access. By way of a non-limiting example, when one customer has a Service Level Agreement (SLA) that guarantees a minimum data throughput level, such as 500 Mbps symmetric service, and another customer has an SLA that guarantees only best effort data throughput, traffic to the higher-tier customer&#39;s modem  108  can be prioritized if network requests from both customers exceed network capacity. QoS policies can prioritize network traffic based on the type of data being transferred. By way of a non-limiting example, traffic that is sensitive to delay, such as streaming video or VoIP (voice over IP), can be prioritized over traffic that can is less sensitive to delay, such as delivering a webpage. In some embodiments, CoS policies can take precedence over QoS policies. By way of a non-limiting example, if a customer with a high CoS is requesting low QoS data, but another customer with a lower CoS is requesting high QoS data, the higher CoS customer&#39;s traffic can be prioritized over the lower CoS customer&#39;s traffic despite the different QoS levels. By way of another non-limiting example, when a customer with an SLA that guarantees 100 Mbps symmetric data service requests 1 Gbps service, CoS policies can be enforced to provide the first 100 Mbps of data while the remainder can be enforced based on QoS policies depending on network traffic to other customers. In alternate embodiments the traffic manager  302  can be absent, such as if network traffic is being delivered on a best effort basis, or if CoS and/or QoS are instead handled by the network controller  304 . 
         [0046]    The network controller  304  can manage network operations performed by the DPU  106 . By way of non-limiting examples, the network controller  304  can handle physical layer (PHY) functions and/or link layer functions such as media access control (MAC). When a dedicated traffic manager  302  is absent, in some embodiments the network controller  304  can perform CoS and/or QoS operations. 
         [0047]    The RF front-end  306  can perform conversion and/or processing operations on data transmissions, such as modulation, upconversion, filtering, amplification, downconversion and/or demodulation. 
         [0048]    The junction  308  can split a connection between the RF front-end  306  and the junction  308  into a plurality of connections to the coaxial ports  112 . In some embodiments one or more of the plurality of coaxial ports  112  can receive power over connected coaxial cables  104 . The junction  308  and/or the individual coaxial ports  112  can be linked to a power tap  310  that is also connected to a power subsystem  312  in the DPU  106 . The power tap  310  can provide power to, and/or draw power from, the power subsystem  312 . 
         [0049]    The power subsystem  312  can be linked to the other components of the DPU  106  via the power tap  310  and/or junction  308 . As such, the power subsystem  312  can manage power received by the DPU  106  through the coaxial ports  112 , and can provide power to the DPU&#39;s components. In some embodiments the power subsystem  312  can comprise one or more batteries that can store power received by the DPU  106  until it is needed to power the DPU  106 . 
         [0050]    In some embodiments the DPU  106  can be reverse powered by one or more other network elements connected to the coaxial ports  112  via coaxial cables  104 . By way of a non-limiting example, modems  108  located in apartment units can be powered by electrical outlets in the units, and those modems  108  can be connected to a DPU&#39;s coaxial port  112  via the coaxial cables  104 . As such, the modems  108  can draw power from electrical outlets in the apartment units and transfer some of that power through the coaxial cable  104  to the DPU&#39;s power subsystem  312  through a coaxial port  112  and power tap  310 . Accordingly, in some embodiments the DPU  106  can be reverse powered without being directly powered at its location within the MDU. In alternate embodiments the DPU  106  can be powered directly from an electrical outlet or other electrical connection. 
         [0051]    A single-band DPU  106  can further comprise a clock subsystem  314  that can provide reference clocks used by other subsystems in the DPU  106 . By way of a non-limiting example, a clock subsystem  314  can be linked to the traffic manager  302  and/or network controller  304 . 
         [0052]      FIG. 4  depicts an exemplary embodiment of a dual-band DPU  106 . A dual-band DPU  106  can comprise two network cable interfaces  114  and one coaxial port  112 . In a dual-band DPU  106 , each network cable interface  114  can be linked to the same traffic manager  302 . In addition to enforcing CoS and QoS, in a dual-band DPU  106  the traffic manager  302  can also perform link aggregation. By way of a non-limiting example, the traffic manager  302  can aggregate a plurality of separate OFDM blocks. The traffic manager  302  can be linked to a junction  308  by two parallel links that each comprise a network controller  304  and an RF front-end  306 . In a dual-band DPU  106 , each RF front-end  306  can convert between binary digital form and different ranges of RF frequencies in the MoCA range. By way of a non-limiting example, one RF front-end  306  can handle data transmissions sent within a first range of MoCA frequencies, while the other RF front-end  306  can handle data transmissions sent within a second range of MoCA frequencies. 
         [0053]    The junction  308  in a dual-band DPU  106  can be linked to the coaxial port  112  through an intermediate power tap  310  that can provide power to, and/or draw power from, a power subsystem  312 . In some embodiments the coaxial port  112  can receive power through a coaxial cable  104  from other network elements, such that the DPU  106  can be reverse powered as described above with respect to the single-band DPU  106  shown in  FIG. 3 . 
         [0054]    A dual-band DPU  106  can further comprise a clock subsystem  314  that can provide reference clocks used by other subsystems in the DPU  106 . By way of a non-limiting example, a clock subsystem  314  can be linked to the traffic manager  302  and/or the network controllers  304 . 
         [0055]      FIG. 5  depicts an exemplary embodiment of a modem  108 . In some embodiments a modem  108  can comprise a modem coaxial port  502 , a modem network cable port  504 , and a modem power connector  506 . The modem&#39;s coaxial port  502  can be connected to a coaxial cable  104  extending through the MDU from a DPU  106 , as described above. The modem  108  can be configured to exchange data with the DPU  106  via the coaxial cable  104  using MoCA. 
         [0056]    A modem network cable port  504  can accept a network cable  116 , such as a CAT5 cable, for linking the modem  108  to another device and sharing network access with that device. While in some situations a modem  108  can be directly linked to a computer or other networked device through a network cable  116 , in other situations a network cable  116  can link the modem  108  to a router that can share the modem&#39;s network access with a plurality of different devices via wired connections and/or wireless connections such as Wi-Fi connections. In alternate embodiments the modem  108  can itself comprise a wired and/or wireless router, such that the modem  108  has a plurality of modem network cable ports  504  for different wired connections to devices and/or can provide wireless data connections to multiple other devices. 
         [0057]    A modem power connector  506  can be a power cable, or a port for accepting a power cable, such that the power cable can transfer electricity from a wall outlet or other power source to the modem  108 . Power received via the modem power connector  506  can power the modem&#39;s operations. In some embodiments power received by the modem  108  can also be passed via the modem coaxial port  502  through coaxial cables  104  to a coaxial port  112  at a DPU  106 , such that the DPU  106  can be reverse powered as described above. In some embodiments a dedicated modem power connector  506  can be absent, and the modem  108  can receive power transmitted over coaxial cables  104  via a modem coaxial port  502 . 
         [0058]      FIG. 6  depicts an alternate embodiment of a modem  108 , in which the modem is a pluggable transceiver. In embodiments in which the modem  108  is a pluggable transceiver, the modem  108  that can be inserted directly into another network device to provide that device with network access. By way of a non-limiting example, a modem  108  can be a small form-factor pluggable (SFP) that can be plugged into a cable box or video gateway to provide it with network access. In this embodiment the modem  108  can comprise a modem coaxial port  502  and pluggable connector that can be inserted into a corresponding port in a network device. In this embodiment the modem  108  can lack a power port, and it can instead receive power through a connected coaxial cable  104  and/or from the connected network device. By way of a non-limiting example, when the port in the network device that receives a pluggable transceiver modem  108  does not provide sufficient power to the pluggable transceiver modem  108 , the pluggable transceiver modem  108  can receive some or all of its power through a coaxial cable  104 . 
         [0059]    A modem  108  can be configured to process network traffic being sent or received via the modem  108 . By way of a non-limiting example, in some embodiments the modem  108  can enforce CoS and/or QoS policies similar to the traffic manager  304  of a DPU  106 . 
         [0060]    As with DPUs  106 , a modem  108  can single-band or dual-band. Dual-band modems  108  can transmit data in two different RF frequency ranges, and as such can transmit more data simultaneously than single-band modems  108 . By way of a non-limiting example, in some embodiments a single-band modem  108  can have 1 Gbps aggregate downstream and upstream data rates, while a dual-band modem  108  can have 2 Gbps aggregate downstream and upstream data rates. Accordingly, in some embodiments a dual-band modem  108  that supports 2 Gbps aggregate speeds can be used when a service level agreement (SLA) with a user indicates symmetric bandwidth of 1 Gbps download speeds and also 1 Gbps upload speeds. 
         [0061]      FIG. 7  depicts an exemplary embodiment in which a power inserter  702  and a network expander  704  are connected via coaxial cables  104  between a DPU  106  and modems  108  in an MDU network  100 . 
         [0062]    A power inserter  702  can be connected to a wall outlet or other power source in an MDU, such that it can provide power via coaxial cable  104  to other elements of the MDU network  100 . By way of a non-limiting example, a power inserter can provide power to the DPU  106  and/or modems  108  such that they can be reverse powered over coaxial cable  104  as described above. 
         [0063]    A network expander  704  can be a repeater element connected between a DPU  106  and one or more modems  108 , such that it can receive and re-transmit data over coaxial cable  104  using MoCA. In some embodiments a network expander  704  can receive an RF signal, downconvert it if necessary, demodulate it, and convert to digital bits, then remodulate it and upconvert it if necessary before transmitting it again. As such, the network expander  704  can examine the digital bits to enforce CoS and/or QoS policies, and/or change destination addresses or other elements of a data packet. By way of a non-limiting example, the network expander  704  can ensure that high CoS modems  108  subtended by the network expander  704  aren&#39;t starved by modems  108  that are not being subtended by that network expander  704 . 
         [0064]    Network expanders  704  can be single-band or dual-band, such that they can receive and re-transmit data in one or two MoCA RF frequency ranges. As shown in  FIG. 7 , in some embodiments a power inserter  702  can provide power to a network expander  704  via intermediate coaxial cable  104 . In alternate embodiments a network expander  704  can receive power directly from its own power connection. 
         [0065]    A network expander  704  can retransmit received data over coaxial cable  104 . As such, the data can be passed over a longer link of coaxial cable  104  without losing throughput. In some embodiments multiple network expanders  704  can be present in series along a line from a DPU  106  to a modem  108 , such that the length of the coaxial cable  104  link can be extended multiple times to reach a unit in an MDU. 
         [0066]    A network expander  704  can also expand the number of modems  108  that can be connected to a DPU  106  in an MDU network  100 . In some embodiments a network expander  704  can be a single network element that manages traffic sent to and from a set of modems  108  subtended by the network expander  704  via a splitter  110 . By way of a non-limiting example, if a DPU  106  natively supports connections with up to 15 modems  108 , a network expander  704  can connect to the DPU  106  as if it were one of those 15 modems  108  such that it can manage traffic to and from a group of subtended modems  108 , thereby allowing more than 15 modems to be connected to the DPU  106 . 
         [0067]      FIG. 8  depicts a non-limiting example of a single-band MDU network  100  in use. In this exemplary embodiment, a single-band DPU  106  connected to an access network  102  has four coaxial ports  112  each linked with a coaxial cable  104  to a splitter  110 . Each splitter  110  can split into a plurality of coaxial cables  104  passing through the MDU to single-band modems  108  in different units. As such, a modem  108  in each unit can be connected to the single-band DPU  106  and gain access to the access network  102 . The single-band DPU  106  and modems  108  can exchange data over the coaxial cables  104  using MoCA. In some embodiments dual-band modems  108  can also be connected to a single-band DPU  106  and exchange data in one of the two bands. One or more network expanders  704  and/or power inserters can also be present to extend any of the lines of coaxial cable  104  between the DPU  106  and modems  108 . 
         [0068]      FIGS. 9A-9C  depict graphs of aggregate data rates measured at different distances using test embodiments of a single-band DPU  106 , a single-band modem  108 , and a single-band network expander  704 . 
         [0069]      FIG. 9A  depicts a graph of aggregate data rates measured during a test at different distances between a single-band DPU  106  and a single-band modem  108 . As shown, in some embodiments aggregate data speeds between a single-band DPU  106  and a single-band modem  108  can be over 1 Gbps using MoCA across a coaxial cable  104  link that is up to 500 feet long. As such, single-band modems  108  connected to a single-band DPU  106  with coaxial cables  104  shorter than 500 feet long can achieve peak aggregate data speeds of over 1 Gbps. 
         [0070]      FIG. 9B  depicts a graph of aggregate data rates measured during a test at different distances between a single-band network expander  704  and a single-band modem  108 . As shown, in some embodiments, a single-band network expander  704  can provide an additional 600 feet of distance at which data can be transferred at 1 Gbps aggregate speeds. 
         [0071]      FIG. 9C  depicts a graph of aggregate data rates measured during a test at different distances between a single-band DPU  106  and a single-band modem  108  when one single-band DPU  106  is present between them. As shown, aggregate data speeds can be over 1 Gbps using MoCA across a coaxial cable  104  link that is up to 1100 feet long when the link is extended with a single-band network expander  704 . 
         [0072]    Accordingly, as shown in  FIGS. 9A-9C , while a single-band modem  108  can achieve peak 1 Gbps aggregate speeds without a network expander  704  when its link to a single-band DPU  106  is less than 500 feet, a single-band network expander  704  can be used to provide peak 1 Gbps aggregate speeds to single-band modems  108  that are farther away within an MDU. Although not shown, additional network-expanders  704  could further increase the distance at which 1 Gbps aggregate speeds could be provided. 
         [0073]      FIG. 10  depicts a non-limiting example of a dual-band MDU network  100  in use. In this exemplary embodiment, a dual-band DPU  106  connected to an access network  102  has one coaxial port  112  connected to a splitter  110 . The splitter  110  can split into a plurality of coaxial cables  104  passing through the MDU to dual-band modems  108  in different units. As such, a dual-band modem  108  in each unit can be connected to the dual-band DPU  106  and gain access to the access network  102 . The dual-band DPU  106  and dual-band modems  108  can exchange data over the coaxial cables  104  using MoCA. In some embodiments single-band modems  108  can also be connected to a dual-band DPU  106  and exchange data in one of the two bands. One or more network expanders  704  and/or power inserters can also be present to extend any of the lines of coaxial cable  104  between the DPU  106  and modems  108 . 
         [0074]      FIGS. 11A-11C  depict graphs of aggregate data rates measured at different distances using test embodiments of a dual-band DPU  106 , a dual-band modem  108 , and a dual-band network expander  704 . 
         [0075]      FIG. 11A  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band DPU  106  and a dual-band modem  108 . As shown, in some embodiments aggregate data speeds between a dual-band DPU  106  and a dual-band modem  108  can be over 2 Gbps using MoCA across a coaxial cable  104  link that is up to 400 feet long. As such, dual-band modems  108  connected to a dual-band DPU  106  with coaxial cables  104  shorter than 400 feet long can achieve peak aggregate data speeds of over 2 Gbps. Additionally, although speeds can decrease at longer distances, in some embodiments dual-band modems  108  connected at up to 650 feet can still achieve aggregate data speeds of over 1 Gbps. 
         [0076]      FIG. 11B  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band network expander  704  and a dual-band modem  108 . As shown, in some embodiments, a dual-band network expander  704  can provide an additional 400 feet of distance at which data can be transferred at 2 Gbps aggregate speeds. 
         [0077]      FIG. 11C  depicts a graph of aggregate data rates measured during a test at different distances between a dual-band DPU  106  and a dual-band modem  108  when one dual-band DPU  106  is present between them. As shown, aggregate data speeds can be over 2 Gbps using MoCA across a coaxial cable  104  link that is up to 800 feet long when the link is extended with a dual-band network expander  704 . Additionally, aggregate data speeds can be over 1 Gbps at over 1000 feet in such an environment. 
         [0078]    Accordingly, as shown in  FIGS. 11A-11C , while a dual-band modem  108  can achieve peak 2 Gbps aggregate speeds without a network expander  704  when its link to a dual-band DPU  106  is less than 400 feet, a dual-band network expander  704  can be used to provide peak 2 Gbps aggregate speeds to dual-band modems  108  that are farther away within an MDU. Although not shown, additional network-expanders  704  could further increase the distance at which 2 Gbps aggregate speeds could be provided. 
         [0079]    As shown in  FIGS. 8 and 10 , the configuration of an MDU network  100  can be customized according to the number of modems  108  to be connected to a DPU  106  and/or the distance of each modem  108  to the DPU  106 . If and when additional modems  108  are to be connected, the MDU network  100  can be expanded with network expanders  704  to provide new modems  108  network access at the same high aggregate speeds as other modems  108  already present in the MDU network  100 . 
         [0080]    In comparison to other MDU networking systems such as G.fast, which provides network access over phone lines, the MDU network  100  described herein can provide higher peak aggregate data speeds to each unit. By way of a non-limiting example, while some G.fast implementations limit units to sharing a network connection with aggregate speeds of 2.5 Gbps downstream and 1.5 Gbps upstream at a peak aggregate rate per unit of only 700 Mbps, some embodiments of a single-band MDU network  100  can share a connection of the same speed at a peak aggregate rate of 1.1 Gbps per unit, while some embodiments of a dual-band MDU network  100  can share a connection of the same speed at a peak aggregate rate of 2.1 Gbps per unit. 
         [0081]    The elements of an MDU network can also use less power than the elements of a G.fast network. By way of a non-limiting example, some G.fast implementations use network elements that use up to 4 watts per unit to provide network access to the MDU&#39;s units. However, test results show that in some embodiments a single-band DPU  106  can use just 0.4 watts per modem  108 , and as such a DPU  106  supporting connections to 15 modems  108  would use 6 watts total for all of its connections instead of 4 watts per unit. Test results also show that in some embodiments a single-band modem  108  can use 8 watts, while a single-band network expander  704  can use 4 watts. Network elements in a dual-band MDU network  100  can use more power, but provide higher aggregate speeds as described above. By way of a non-limiting example, test results show a dual-band DPU  106  using 16 watts total, a dual-band modem  108  using 14 watts, and a dual-band network expander using 16 watts. Moreover, the DPU  106  and/or modems  108  in an MDU network  100  can be reverse powered using electricity passed to them over coaxial cable  104  from other locations in the MDU. 
         [0082]      FIGS. 12A-12D  depict exemplary embodiments of an MDU network that can coexist with television equipment that uses the same coaxial cables  104 . Television equipment can include a television source  1200  for the MDU and a television receiver  1202  in each of the MDU&#39;s units. The television source  1200  can be one or more devices that provide television signals to the television receivers  1202 , such as a switch that distributes television signals received from a satellite dish on the MDU&#39;s roof. The television receivers  1202  can be one or more devices that receive and/or play back television signals, such as televisions or set-top boxes. 
         [0083]      FIG. 12A  depicts an embodiment in which a television source  1200  and a DPU  106  both feed into a combiner  1204  linked to a shared coaxial cable  104 . The coaxial cable  104  can run to a unit at the MDU, where a splitter  110  can divide the coaxial cable  104  between a modem  108  and a television receiver  1202 . As such, the television source  1200  can provide television signals to the unit&#39;s television receiver  1202  using one range of RF frequencies, while the DPU  106  can simultaneously provide network access to the unit&#39;s modem  108  over the same coaxial cable  104  using single-band or dual-band ranges of RF frequencies. 
         [0084]      FIG. 12B  depicts an embodiment in which a DPU  106  feeds into a splitter  110  that can lead to a plurality of different combiners  1204 . Each combiner  1204  can also receive television signals over a different link from a television source  1200 , such that the combiner  1204  can pass both data and television signals over a link of coaxial cable  104  to a unit in the MDU. 
         [0085]      FIGS. 12C and 12D  depict embodiments in which a network expander  704  is present between a DPU  106  and a splitter  110 . A coaxial cable  104  from the splitter  110  can then feed into a combiner  1204  that also receives a signal from a television source  1200 . As with the embodiment of  FIG. 12A , in these embodiments a coaxial cable  104  can lead from the combiner  1204  to a unit in the MDU such that a modem  108  and a television receiver  1202  in the unit can both receive signals through that coaxial cable  104 . 
         [0086]    As shown in  FIG. 12C , in some embodiments the network expander  704  can be used to extend the distance between the DPU  106  and other equipment, such that data can be transmitted over longer distances via coaxial cable  104  before data speeds decrease. By way of a non-limiting example, when a television source  1200  such as a television antenna or satellite dish is located on an MDU&#39;s roof but the DPU  106  is located in the MDU&#39;s basement, a network expander  704  can be used to extend a link of coaxial cable  104  to a location in the MDU at which it can be linked to a combiner  1204  that is also linked with the television source  1200 . 
         [0087]    As shown in  FIG. 12D , in some embodiments the network expander  704  can also, or alternately, be used to feed into a splitter  110  that can expand the number of modems  108  that can be connected. By way of a non-limiting example, a link from the DPU  106  can feed into a network expander  704 , which can feed into a splitter  110  that splits the line of coaxial cable  104  into a plurality of different units in the MDU. As shown in  FIG. 12D , each line passing into a unit can also be combined with a line from a television source  1200  such the unit can receive both data and television signals. 
         [0088]    Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the invention as described and hereinafter claimed is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.