SBM powered by Microsoft Lync Administrator's Guide 2010-11

6-10
Troubleshooting
Implement a Loopback
Connect the Port to be Tested
You have three options for connecting the port that you plan to put into local
loopback:
Leave the port connected to the Telco.
Table 6-2. Pinout
Connect the port to a loopback connector. Use an RJ-45 cable in which
you have tied the pins together as shown in the table below.
Table 6-3. Pinout for Loopback Connector
Connect the port to another E1/T1 port on your SBM. In this case, you
must use a crossover cable.
Table 6-4. Pinout for Crossover Cable
Pin Signal
1RRING
2RTIP
4TRING
5TTIP
Pin Pin
14
25
Pin Pin
14
25
41
52