CSU: PPP Line Statistics

• LOS, which means loss of signal.

• LFA, which means loss of frame alignment.

• AIS, which means all ones

• RFA, which means remote facility alignment.

• None, which means there are no alarms.

• Yellow alarm, which typically means that the telephone company is testing the line. If this condition persists, however, this may indicate that long haul/short haul parameters in your driver configuration are incorrect.

• Blue alarm, which means that the telephone company is testing the line.

• Red alarm, which indicates an out-of-frame condition or loss-of-signal condition.

• None, which means loopback testing is not being done.

• Local, which means that an adapter-level loopback test is underway.

• Line, which means that a loopback test between the switch and the adapter is underway.

• Payload, which means that a line loopback test involving just the payload of a particular channel is underway.