14-2 Diagnostics
Model No.
Running Head

User port Diagnostics System Testing and Diagnostics

14.3 User port Diagnostics

14.3.1 WAN Diagnostics

Software-initiated diagnostics on T1 WAN aggregates involve looping the WAN signal
toward the network (line loopback) or the system (local loopback) and placi ng any one of the
DS0 channels that make up the WAN signal in local loopback. The table below list detailed
information on the diagnostic capabilities of the WAN ports.
Loopbacks
On-port loopbacks
T1 Line loopback Toward Network Yes
T1 Local loopback Toward User Yes
DS0 Channel loopback Toward Network No
DS0 Channel loopback Toward User Yes
In-Band loopback Code Generation
Industry-Standard T1 Loop-Up Code N/A
Industry-Standard T1 Loop-Down Code N/A
In-Band loopback Code Detection
Industry-Standard T1 Loop-Up Code N/A
Industry-Standard T1 Loop-Down Code N/A
Bit Error Rate Tester (BERT)
Patterns Supported
All 1s Yes
All 0s Yes
1:1 Yes
1:7 Yes
511 No
2047 No
3:24 Yes
QRSS Yes
BERT Direction
Toward User No
Toward Network Yes
Statistics Gathered by BERT
Bit Errors (BE) Yes
Errored Seconds (ES) Yes
Severely Errored Seconds (SES) Yes
Consecutive Severely Errored Seconds Yes
Out of Synchronization Seconds (OOS) Yes
Bit Error Rate (BER) Yes
Elapsed Seconds (ELAP) Yes