Monitoring and Testing
4-19
3166-A2-GB20-20
March 1999
Local Loopback Tests
The Local Loopback tests enable you to conduct circuit testing and fault isolation
for the digital line. The supported local loopback tests are:
Line Loopback
(LLB)
Payload Loopback
(PLB)
Repeater Loopback
(RLB)
Data Channel Loopback
(DCLB)
Data Terminal Loopback
(DTLB)
The Line Loopback command can be activated and deactivated in response to
commands received over the network interface. The Network Interface
configuration option NET LLB controls whether the DSU/CSU responds to the
commands transmitted on the network interface to initiate LLBs (see Appendix C,
Configuration Options
).
The data port configuration option NET DCLB controls whether the DSU/CSU
responds to inband V.54 commands to initiate DCLB for that port (see
Appendix C,
Configuration Options
).
Local loopback tests can be aborted (Abort Command) at any time.
Local loopback tests cannot be run if send pattern or remote loopback tests are
active. In most cases local loopbacks cannot run with each other. Table 4-7
shows valid combinations of local loopbacks.
Table 4-7.
Valid Loopback Combinations
LLB
PLB
RLB
DCLB
DTLB
LLB
NO
NO
YES
NO
YES
PLB
NO
NO
NO
NO
YES
RLB
YES
NO
NO
NO
YES
DCLB
NO
NO
NO
NO
NO
DTLB
YES
YES
YES
NO
NO
Summary of Contents for 3166 CSU
Page 1: ...ACCULINK 3166 DSU CSU USER S GUIDE Document No 3166 A2 GB20 20 March 1999...
Page 16: ...About This Guide x 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 20: ...Introduction 1 4 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 68: ...SDCP Operation 3 42 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 102: ...SDCP Menu A 2 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 140: ...Pin Assignments D 12 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 166: ...SNMP MIB Objects E 26 3166 A2 GB20 20 March 1999 This page intentionally left blank...
Page 192: ...Equipment List I 2 3166 A2 GB20 20 March 1999 This page intentionally left blank...