Cisco 10000 Series Configuration Manual page 111

Chapter 4 4-Port Channelized T3 Half-Height Line Card Configuration
The 4-Port Channelized T3 Half-Height line card sends the following code for remote line FDL
Bellcore (SmartJack) loopback:
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–
remote line inband [maintenance] sends a repeating inband pattern to the remote end, requesting
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entry into a network line loopback. The inband loopback request overwrites all data in the T1 with
the loop request pattern. The remote end responds to this code only after it receives the pattern
continuously for at least five seconds.
The maintenance keyword is new in 12.2(28)SB. The maintenance keyword sends loopback codes
to an interface on the remote end of the connection. This sets loopback on the remote end interface.
(Note that the 4-Port Channelized T3 Half-Height line card does not respond to inband maintenance
codes.)
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remote payload [fdl | ansi] sends a repeating, 16-bit ESF data link code word to the remote end,
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requesting entry into a network payload loopback. Using fdl and ansi enables the remote payload
facility data link (FDL) ANSI bit loopback on the T1 channel. Loopback codes are defined in
ANSI T1.404-1989 Table 3 (Assigned Bit-Oriented ESF Data-Link Messages).
Note
The 4-Port Channelized T3 Half-Height line card sends the following code for remote payload FDL
ANSI loopback:
–
–
Use the no form of the command to terminate a loopback.
For more information on this command, refer to the online
Troubleshooting
The following are examples of configuring loopback mode:
• Configure the T3 controller for local loopback on T1 interface 1.
Router(config)# controller t3 1/0/0
Router(config-controller)# t1 1 loopback local
Configure the T3 controller for remote FDL ANSI loopback on T1 interface 1.
•
Router(config)# controller t3 1/0/0
Router(config-controller)# t1 1 loopback remote line fdl ansi
OL-8834-04
Network Use (loopback active) Code: 0 001001 01111111
Network Use (loopback deactivate) Code: 0 010010 01111111
Repeating Inband Loopback Activate Code (SF framing): 00001 loop up code
Repeating Inband Loopback Deactivate Code (SF framing): 001 loop down code
Repeating Inband Loopback Activate Code (SF and ESF framing): 2 in 5 loop up code
Repeating Inband Loopback Deactivate Code (SF and ESF framing): 3 in 5 loop down code
Due to hardware constraints, when you execute the t1 loopback remote payload command, the
type of loopback that is implemented is line loopback.
Payload Loopback Active Code: 0 001010 011111111
Payload Loopback Deactivate Code: 0 011001 011111111
Guide.
Cisco 10000 Series Internet Router
Cisco 10000 Series Router Line Card Configuaration Guide
Channelized T1 Commands
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