Cisco SGE2000 Configuration Guide - Page 138

External Optical Bypass Functionality Appendix A The External Optical Bypass Module External Optical Bypass Functionality The External Optical Bypass module is connected bump-in-the-wire in the GBE link. It is then connected to the SCE 2000 platform with two types of connections: • GBE optical connections for data link traffic - GBE connections from the External Optical Bypass module to one pair of the GBE line ports. • Power and Control connection - Connection to a dedicated connector on the SCE 2000 platform back panel, so the SCE 2000 platform can provide power to the External Optical Bypass module. (Note that the power connection also provides the logical control functionality.) The External Optical Bypass module is normally inactive, (not in bypass), and simply transfers the two GBE signals to and from the SCE 2000 platform. In case the SCE 2000 platform stops providing power to the External Optical Bypass module, or in case the power cable is disconnected from the optical bypass module, the External Optical Bypass module becomes active, bypassing the two GBE links to the SCE 2000 platform, and thus preserving network connectivity. The figure below illustrates the operation of the bypass module when it is inactive (not in bypass). The data traffic is simply transferred through the bypass module to the SCE 2000 platform. The figure below illustrates the operation of the bypass module when it is active (in bypass). The data traffic flows through the bypass module, and the GBE link no longer includes the SCE 2000 platform. Note that when the bypass module is active, it puts the SCE 2000 platform into a loop connection, creating a shortcut between the SCE 2000 platform GBE interfaces. The External Optical Bypass Module Front Panel The front panel of the External Optical bypass module contains the following components: • SUB Rx/Tx - GBE port that connects to the network element on the Subscriber side of the link. • NET Rx/Tx - GBE port that connects to the network element on the Network side of the link. • CONTROL - RJ-45 port that connects to the Bypass connector on the rear panel of the SCE 2000 platform. The SCE 2000 platform controls the External Optical Bypass module via this connection, by the presence or absence of electrical power. • Pigtail fiber connectors - Four fiber cables that connect to the GBE link ports on the front panel of the SCE 2000 platform - NET Tx - NET Rx - SUB Tx - SUB Rx • No Bypass LED: - ON = Bypass module is not active (GBE traffic flows through the SCE 2000 platform) - OFF = Bypass module is active (GBE traffic flows through the bypass module) Cisco SCE 2000 4xGBE Installation and Configuration Guide A-2 OL-7824-06