WAN Module Installation and User Guide
2-11
Monitoring WAN Physical Links
Far-End Loopback Modes
The far-end of T1 links can be enabled for the following two loopback modes:
•
Remote Line
•
Remote Payload
The far-end of T3 links can be enabled for the following loopback mode:
•
Remote Line
The remote line mode reflects the received signal back to the near-end. The remote
payload mode reflects the data and regenerates the framing information back to the
near-end.
Figure 2-5: Remote line loopback mode
Remote Line Loopback Mode.
When the local port is enabled for remote line
loopback mode, it sends a request to the remote end to enter the equivalent of network
line loopback mode. The signal transmitted to the remote end will be retransmitted as
received back to the local end.
Note: If the T1 line is configured to use the ATT FDL standard, the remote end
must be configured to detect inband loopback requests for the remote end to
enter remote line loopback mode.
XM_014
Remote WAN Port
Local WAN Port
Framer
Data in
Data out
Data out
Data in
Framer
