CANOGA PERKINS L351 10/100BASE Media Converter - Manual (Page 23)

EdgeAccess Universal Chassis System
L351 10/100BASE Media Converter 3-5/(3-6 Blank)
• Local-Remote mode loops the optical data that the Remote L351 receives on the Extension Port
Rx through the User PHY to the Extension Port Tx. The data is not sent out the remote User Port
Tx and incoming data on the remote User Port Rx is ignored. See Figure 3-5. To set this mode at
the Diagnostics screen, set the Loopback State for the Local module to Remote.
Figure 3-5. Local-Remote Loopback Mode
• Remote-Local mode loops the electrical data that the Remote L351 receives on the User Port Rx
through the FPGA to the User Port Tx. The data is not sent out the remote Extension Port Tx and
incoming data on the remote Extension Port Rx is ignored. See Figure 3-4. To set this mode, at
the Diagnostics screen, set the Loopback State for the Remote module to Local.
Figure 3-6. Remote-Local Loopback Mode
• Remote-Remote mode loops the optical data that the Local L351 receives on the Extension Port
Rx through the Local User PHY to the Extension Port Tx. The data is not sent out the local User
Port Tx and incoming data on the local User Port Rx is ignored. See Figure 3-5. To set this mode,
at the Diagnostics screen, set the Loopback State for the Remote module to Remote.
Figure 3-7. Remote-Remote Loopback Mode
For loopback, the L351 uses a unique MAC address that is listed on the Diagnostics screen as Loop
Test MAC Address; for details about using the software and accessing the Diagnostics screen, see
Chapter 4. In loopback mode, the L351 filters the incoming packets to identify the test packets
through the MAC address. You can set two diagnostics options if you want to alter the data during
loopback, Swap MAC Address at Loopback Point, which swaps the test MAC address with the
source MAC address, and Recalculate CRC at Loopback Point. The test packets are returned to the
source according to the selected mode.