Patent Publication Number: US-7223027-B2

Title: Optical communications adapter module configured for use inside a XENPAK-sized module

Description:
FIELD OF THE INVENTION 
   The present invention relates to apparatus and methods for optical data transmission and, more particularly, to converting between optical communications module formats. 
   BACKGROUND OF INVENTION 
   Optical components are modular building blocks that enable networking and communications equipment manufacturers to create standards based products to communicate data over optical data lines. 
   Therefore, there is a need to convert between different optical data transmission card standards in an intelligent, cost effective manner. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings. To facilitate this description, like reference numerals designate like structural elements. The invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. 
       FIG. 1  shows an optical communications network in accordance with one embodiment of the present invention. 
       FIG. 2  shows a conversion from an XPAK module to an optical communications adapter module in accordance with one embodiment of the present invention. 
       FIG. 3  shows an exploded view of an optical communications board assembly being utilized to generate an optical communications module in accordance with one embodiment of the present invention. 
       FIG. 4  shows a substantially assembled view of an optical communications adapter module utilizing an XPAK board assembly in accordance with one embodiment of the present invention. 
       FIG. 5  illustrates an XPAK board assembly that has been electrically converted to fit into a XENPAK-sized casing to generate an optical transmission adapter module in accordance with one embodiment of the present invention. 
       FIG. 6  illustrates a side view of the optical communications adapter module in accordance with one embodiment of the present invention. 
       FIG. 7  illustrates an XFP board assembly that has been electrically converted to fit into a XENPAK-sized casing to generate an optical transmission adapter module in accordance with one embodiment of the present invention. 
       FIG. 8  illustrates a XENPAK-sized module utilizing an XFP board assembly board in accordance with one embodiment of the present invention. 
       FIG. 9  illustrates a top view of a conversion board in accordance with one embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
   In the following detailed description, reference is made to the accompanying drawings which form a part hereof wherein like numerals designate like parts throughout, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents. 
   XENPAK (10 Gigabit Ethernet Transceiver Package), XPAK (e.g., 10 Gigabit Package but shorter than XENPAK), X 2 , and XFP (10 Gigabit Small Form Factor Pluggable) are different optical communications transmission module standards resulting from multi-source agreements (MSA&#39;s) among several manufacturers with regard to 10 Gigabit Ethernet optical transmission cards. XENPAK, XPAK, X 2 , and XFP define optical transceivers which conform to the 10 Gigabit Ethernet standard as stated by the IEEE (Institute of Electrical &amp; Electronics Engineers) 802.3. 
   XENPAK generally utilizes SC (subscription channel) fiber optic connectors on one end and utilizes an industry standard 70 pin electrical connector on the other end to connect with client computing devices to facilitate data communications to a network or any suitable type of computing and/or telecommunications device. As known to those skilled in the art, an SC connector is a fiber optic connector. XENPAK modules generally utilize a four wide XAUI (10 gigabit per second attachment unit interface) and are configured to be hot pluggable. 
   The XPAK is generally a 10 gigabit hot pluggable module that provides flexible I/O and PCI compatibility. On one end, the XPAK assembly board utilizes a standard 70 pin electrical connector to connect with client computing devices to facilitate data communications with a network or other computing and/or telecommunication devices through the optical connectors. On the other end, the XPAK board assembly within the XPAK module generally utilize LC connectors to connect to other computing devices and/or networks. 
   Embodiments of the present invention can enable a board assembly from the XPAK module to be used in a XENPAK-sized packaging unit (also known as casing). This enhances the flexibility of optical communication card manufacturers because a board assembly designed to fit into a XPAK module can be utilized in a XENPAK-sized casing. Without using the embodiments of the present invention, the same board assembly of an XPAK module would create an incorrect position of the optical interface when placed within the XENPAK-sized casing. By use of the embodiments of the present invention this optical offset may be corrected and therefore such an offset is not present at the XENPAK-sized casing even when an XPAK board assembly is utilized. 
   X 2  modules with X 2  board assemblies are extremely similar in structure to XPAK modules. One difference between the X 2  board assembly and the XPAK board assembly is that the X 2  board assembly utilizes SC connectors as opposed to LC connectors. Besides using different optical connectors, X 2  and XPAK have similar functionalities and structures. Consequently, by utilizing the embodiments of the present invention, it should be appreciated that X 2  board assemblies may also be utilized in a XENPAK-sized casing to generate an X 2  to XENPAK adapter module. 
   In yet another embodiment, an XFP board assembly may be used from an XFP module for conversion into a XENPAK-sized module. This may be accomplished by utilizing a board extender for the XFP board assembly to extend the XFP electrical connector. 
     FIG. 1  shows an optical communications network  100  in accordance with one embodiment of the present invention. In one embodiment, the communications network  100  includes a server  102 , router  104 , and a hub  106  that is in communication with a network  108 . It should be appreciated that the server  102 , router  104 , and the hub  106  are exemplary computing apparatuses (e.g., client devices, client computing devices, etc.) that may be in optical communication with the network  108 . In one embodiment, the client device may include a microprocessor and a network processor coupled to one another. It should be appreciated that the network processor and the microprocessor may be coupled in any suitable fashion. Consequently, any suitable types and/or numbers of computing or telecommunications devices may utilize an optical communications adapter module  110  (e.g., XPAK board assembly to XENPAK-sized module, X 2  board assembly to XENPAK-sized module, XFP board assembly to XENPAK-sized module, etc.) described herein to communicate with the network  108 . The module  110  as described herein may be any apparatus that may be of any suitable configuration that can facilitate data communications utilizing an optical communications assembly board from one type of optical communications device within a packaging or casing of another optical communications device with a different size and/or configuration. In one embodiment, the module  110  is a XENPAK-sized module or transponder that utilizes an assembly board from a different type of optical communications module such as, for example, an XPAK assembly board, an X 2  assembly board, an XFP assembly board, etc. 
   It should also be appreciated that the network  108  may be include any suitable type and/or number of computing or telecommunications device(s). In one embodiment, each of the server  102 , router  104 , and the hub  106  includes the adapter module  110 . Although the module  110  is depicted as being outside of the server  102 , router  104 , and the hub  106  to show that communication with the network is facilitated by the module  110 , the module  110  for each of the computing devices may be contained internally within the server  102 , router  104 , and the hub  106 . In one embodiment, the module  110  may connect to a bus of a computing device. Therefore, it should be appreciated that any module  110  may be connected in any suitable fashion to the computing device as long as the optical connectors of the module  110  may be accessed to communicate with other devices. The optical communications adapter module  110  may be any suitable device that includes one type of optical communications assembly board such as, for example, an XPAK board assembly, an X 2  board assembly, XFP board assembly, etc., that has been utilized to generate another optical communications module of a different type such as, for example, a XENPAK-sized module. It should be appreciated that a board assembly may be any suitable card or board with circuitry or components that enables computing functions such as, for example, optical communications between the client computing device and external computing devices and/or networks. 
   An XPAK board assembly may be utilized to generate a XENPAK-sized module by using optical conversion cords as described in further detail in reference to  FIGS. 2–4 . 
   In another embodiment, the XPAK board assembly within an XPAK module may be utilized to generate a XENPAK-sized module using an electrical extension conversion card as described in reference to  FIGS. 5 and 6 . In yet another embodiment, the optical communications adapter module  110  may include an X 2  board assembly coupled with optical extension cords inserted into a XENPAK-sized module. In a further embodiment, the optical communications adapter module  110  may include an XFP board assembly coupled to a conversion board as described in reference to  FIGS. 7–9 . 
     FIG. 2  shows a conversion from an XPAK module  112  to an optical communications adapter module  110  in accordance with one embodiment of the present invention. In one embodiment, the XPAK module  112  may be converted into the optical communications adapter module  110  by placing an optical communications board assembly such as the XPAK board assembly from the XPAK module  112  into a XENPAK-sized packaging unit. The XPAK module  112  is generally smaller than a XENPAK-sized packaging unit/casing and utilizes a different type of optical connectors. A typical XPAK module utilizes LC optical connectors  114  and  116  while a typical XENPAK module utilizes SC optical connectors  118  and  120 . As discussed in further detail in reference to  FIGS. 5–6 , the XPAK board assembly may be placed at a rear portion of the XENPAK-sized packaging unit and optical conversion cords may be utilized to reposition optical connectors of the XPAK board assembly to locations typically utilized in XENPAK-sized modules. 
   In addition, in one embodiment, the optical conversion cords may convert the XPAK LC optical connectors to optical connectors as described in further detail in reference to  FIG. 3 . Therefore, in such a conversion, the XPAK module  112  can be converted to a XENPAK-sized module in an intelligently and in a cost effective way by utilizing the XPAK board assembly and optical conversion cords within a XENPAK-sized packaging unit. 
   In a further embodiment, X 2  modules may be utilized to generate a XENPAK-sized module by inserting the X 2  board assembly at a rear portion of the XENPAK-sized casing and coupling optical conversion cords to the X 2  board assembly to reposition optical connectors of X 2  board assemblies to locations typically utilized in XENPAK-sized modules. In this type of embodiment, if SC connectors are desired in the optical communications adapter module  110 , optical extension cords may be utilized with SC connectors on both ends rather than optical conversion cords with SC connectors on one end and LC connectors on the other end (as utilized if XPAK board assemblies were being used). 
   In another embodiment, as discussed in reference to  FIGS. 5 and 6 , the XPAK module  112  can be converted to a XENPAK-sized module by utilizing an electrical conversion card to extend an XPAK card to a length typically found in a XENPAK-sized module. The electrical conversion card may include connectors that can electrically couple with the XPAK board assembly and communicate the electrical signals from the XPAK board assembly to a client computing system connector. The client computing system connector may be any suitable connector that can communicate data to any suitable computing device or system that is configured for data transmission and reception such as, for example, server  102 , router  104 , and/or hub  106 . 
     FIG. 3  shows an exploded view of an optical communications board assembly being utilized to generate an optical communications module in accordance with one embodiment of the present invention. In one embodiment, the optical communications board assembly is an XPAK board assembly  136  positioned within a XENPAK-sized case so the electrical connections on one end of the XPAK board assembly  136  is located at an end of the XENPAK-sized case which connects to a client computing device. In such an embodiment, a XENPAK-sized module is generated that can facilitate data communications. 
   In one embodiment, the XENPAK-sized case includes a top cover  130 , a bottom portion  134 , and a face plate  138 . When the XPAK board assembly  136  is positioned in the aforementioned manner, the optical connectors  114  and  116  of the XPAK board assembly  136  are not positioned so the connectors  114  and  116  reach to the face plate  138 . Therefore, one end of each of optical conversion cords  132  and  140  are coupled to the optical connectors  114  and  116  respectively. The second end of each of the optical conversion cords  132  and  140  are positioned to be located at connector openings in the face plate  138  where XENPAK optical connectors from a XENPAK board assembly would be located. 
   In one embodiment, the optical conversion cords  132  and  140  may each have a first end that has the SC optical connector and have a second end that has the LC optical connector. The SC optical connectors and the LC optical connectors may be coupled to each other by fiber optics that have the capability to communicate data. In such embodiments, the optical conversion cords  132  and  140  may be utilized where, for example, the optical communications board assembly has LC optical connectors (e.g., XPAK board assemblies) and the SC connectors are required in the optical communications conversion module. In one embodiment, the fiber optics may have some lag so the fiber optics are longer than the distance between the optical connectors  114  and  116  and the face plate  138 . It should be appreciated that the fiber optics coupling the SC and LC connectors may be any suitable length as long as the connectors of the XPAK may be extended to the location of the face plate  138 . 
   As discussed above, for X 2  assembly board to XENPAK-sized module conversions, an X 2  board assembly from an X 2  module may be utilized in the above described conversion for XPAK modules except, in such an embodiment, the optical conversion cords  132  and  140  may have the same type of connectors (e.g., SC connectors) on both ends because X 2  PC board assemblies typically utilize SC connectors assuming that SC connectors are desired for the XENPAK-sized adapter module. 
     FIG. 4  shows a substantially assembled view of an optical communications adapter module  110  utilizing an XPAK board assembly  136  in accordance with one embodiment of the present invention. In one embodiment, the components as discussed in reference to  FIG. 3  are assembled and positioned into the bottom portion  134  of the XENPAK-sized case. 
     FIG. 5  illustrates an XPAK board assembly  136  that has been electrically converted to fit into a XENPAK-sized casing to generate an optical transmission adapter module  110 ′ in accordance with one embodiment of the present invention. In one embodiment, when the optical connectors  114  and  116  of the XPAK board assembly  136  are placed in optical connector openings of the face plate  138  of a XENPAK-sized casing, the electrical connector  142  does not reach to a back end of the XENPAK-sized casing and therefore, the XPAK board assembly  136  cannot be connected to a client computing device by itself due to the size differential. 
   In one embodiment, the electrical connector  142  of the XPAK board assembly  136  is coupled to a receptacle interface  204 . The receptacle interface  204  may be a part of an extender board  202 . The receptacle interface  204  may be a  70  pin receptacle interface with a female connector that can connect to the electrical connector  142  of the XPAK board assembly  136  which in one embodiment, is a male  70  pin connector. The other end of the receptacle interface  204  may be a part of or may be connectable to the extender board  202  which is configured to communicate the electrical signals from the electrical connector  142  to an electrical connector  142 ′ which, in one embodiment, has the same physical and electrical configuration as the electrical connector  142 . In one embodiment, the electrical connector  142 ′ has a  70  pin interface. In other embodiments, the electrical connector  142 ′ may be different than the electrical connector  142  depending on the type of connections that are utilized by the client computing device to which the module is connected. 
     FIG. 6  illustrates a side view of the optical communications adapter module  110 ′ in accordance with one embodiment of the present invention. The optical communications adapter in one embodiment, may be an XPAK board assembly connected to an extender board  202  within a XENPAK-sized adapter module as discussed above in reference to  FIG. 5 . In one embodiment, the XPAK board assembly  136  is shown as the card between the face plate  138  and the interface  204 . The extender board  202  may be located between the interface  204  and the back portion of the XPAK to XENPAK-sized conversion module. The board extender may be any suitable PC card that is connectable to the interface  204  that is capable of communicating data between the electrical connector  142  and the electrical connector  142 ′. 
   In one embodiment, the extender board  202  may be a PC board with lines capable of transmitting data between the connectors  142  and  142 ′. It should be appreciated that the adapter module  110 ′ with the PC board extender and the interface  204  may be utilized to make the optical connectors of the XPAK board assembly fit into connector openings of the front plate of the XENPAK-sized casing. 
   Therefore, by using the adapter module  110 ′, an XPAK board assembly can be converted into a XENPAK-sized communications module. 
   In one embodiment, without using optical conversion cords, the module  110  may have LC connectors instead of SC connectors. Therefore, if desired, a XENPAK-sized communications module may be generated without the SC connectors if such an embodiment is desired. In yet another embodiment, the adapter module with the extender board  202  may utilize an optical connector conversion cord, as discussed above in reference to  FIGS. 1 through 4 , to convert the LC connectors of an XPAK board assembly to connectors. If an X 2  board assembly has been utilized, such a conversion is not necessary if SC connectors are desired because as indicated above, the X 2  PC board assemblies generally use SC optical connectors even though in most other aspects, the X 2  PC board assemblies are similar to the XPAK board assemblies. 
     FIGS. 7 and 8  describe usage of an XFP board assembly within a XENPAK-sized casing to generate a XENPAK-sized module. As a result, the functionality of an XFP assembly may be applied in an intelligent and cost effective manner where XENPAK modules are often utilized. In addition, entities that utilize XENPAK-sized modules can use the adapter modules  110  in their current line cards without any additional engineering design cost or risk. Consequently, two different solutions do not have to be developed to two different product lines. 
     FIG. 7  illustrates an XFP board assembly  202  that has been electrically converted to fit into an XENPAK-sized casing  216  to generate an optical transmission adapter module  110 ″ in accordance with one embodiment of the present invention. In one embodiment, an XFP board assembly from an XFP module is placed in the XENPAK-sized casing  216 . In one embodiment, the XFP board assembly may be positioned so the optical connectors are accessible through openings in the face plate  218  of the casing  216  of a XENPAK-sized module. It should be appreciated that, depending on the configuration desired, the XFP board assembly  202  may also be utilized with the optical conversion cords to be positioned in any suitable location within the XENPAK-sized casing  216 . 
   When the XFP board assembly  202  is attached to the face plate  218  of the XENPAK-sized casing  216 , a board converter  205  may be utilized to extend the data communication from the XFP board assembly  202  to a rear portion of the casing  216  where an electrical connector  208  may enable coupling and communication with a client computing device. 
   Generally XFP board assemblies communicate data from the optical connectors to a client computing device through a serial 10G electrical signal. XENPAK modules on the other hand communicate data from the optical connectors. As discussed above, XENPAK modules generally utilize four wide XAUI interface (10 gigabit per second attachment unit interface) to communicate four lanes of data each communicating data at almost 3 gigabits per second. Therefore, to convert the XFP electrical signal to what XENPAK generally utilizes requires a XAUI to serial chip  206 . The XAUI to serial chip  206  is known to those skilled in the art. Therefore, if data communication format as typically utilized by XENPAK modules is desired, the board converter  205  may be used to convert a data transmission type from a XFP type to XENPAK type and vice versa. The board converter  205  may utilize a XAUI to serial chip  206  to convert serial data from the XFP board assembly to a four wide XAUI data communication. 
     FIG. 8  illustrates a XENPAK-sized module utilizing an XFP board assembly  202  in accordance with one embodiment of the present invention. In one embodiment, the XFP board assembly  202  may be positioned in the XENPAK-sized casing  216  such that optical connectors  210  and  212  are located in optical connector openings of a face plate  218 . The XFP board assembly  202  may be connected to the conversion board  205 . The XFP board assembly  202  may have optical connectors  210  and  212  on one end and an electrical connector  204  on a second end. In one embodiment, the electrical connector  204  is a 30 pin electrical connector. It should be appreciated that the XFP board assembly  202  may have any suitable type of electrical connector  204  opposite to the optical connector end. The electrical connector  204  may be connected to a conversion board  205  through the electrical connector  204 . In one embodiment, the conversion board  205  may be an XFP to XENPAK conversion board which includes an electrical pin receptacle which may connect with the electrical connector  204 . The XFP to XENPAK conversion board may include a XAUI to serial chip  206  that may convert the serial data communication utilized by the XFP board assembly  202  to and from XAUI data communication typically utilized by XENPAK modules. The XFP to XENPAK conversion board  202  may also include other circuitry like a microprocessor that may manage the optical connectors of the XFP board assembly  202 . 
     FIG. 9  illustrates a top view of a conversion board  205  in accordance with one embodiment of the present invention. The conversion board  205  may be configured to have a connector or a receptor that has the capability to couple and communicate with the electrical connector on the XFP board assembly. On the other end of the conversion board  205 , an electrical connector  208  may be configured to communicate data with a client computing device to which the module is designed to couple with. In one embodiment, the electrical connector  208  is a  70  pin electrical connector as is typically utilized in a XENPAK board assembly. 
   In one embodiment, the conversion board  205  may include the XAUI to serial chip  206 . The XAUI to serial chip  206  may be any suitable integrated circuit capable of converting XAUI data signals to serial data signals and vice versa. Therefore, the XAUI to serial chip  206  may be configured to communicate with the electrical connectors  208  and the XFP board assembly. In one embodiment, the conversion board  205  may communicate with a client computing device by using a four lane XAUI format while the conversion board  205  may communicate with the XFP assembly board through 10 Gigabit per second serial data communications. 
   Another difference between data transmission between the XFP standard and the XENPAK standard is that the XFP standard generally utilizes data communication with a client computing device via an I2C interface as opposed to an management data input/output (MDIO) interface through the  70  pin XENPAK connector. Therefore, the conversion board  205  may also be configured to connect with an I2C interface of the XFP assembly board on one end and also be configured to connect using an MDIO interface on the other end to connect with a client computing device. 
   In one embodiment, the conversion board may also include a microprocessor  222  which may manage optical data communications of the XFP board assembly. In one embodiment, the microprocessor may assist in managing, monitoring, controlling, and alarming with respect to the laser system of the XFP board assembly. In one embodiment, the microprocessor  222  may monitor, manage, adjust, and/or generate data signals that control the laser for the optical communications. For example, the microprocessor  222  may control laser on/off, bias, temperature, input power, health of optics, etc. In another embodiment, the microprocessor may assist with any necessary conversion of data between data communication typically utilized by the XENPAK and the XFP. Therefore, the conversion board  205  may not only extend the XFP to a back portion of the XENPAK-sized casing and translate data between the XFP board assembly and the client computing device, but the conversion board  205  may also assist in managing the operation of the XFP board assembly. 
   Although specific embodiments have been illustrated and described herein for purposes of description of preferred embodiments, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations calculated to achieve the same purposes may be substituted for the specific embodiment shown and described without departing from the scope of the present invention. Those with skill in the art will readily appreciate that the present invention may be implemented in a very wide variety of embodiments. This application is intended to cover any adaptations or variations of the embodiments discussed herein. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.