Carrier Access Access Navigator - Manual (Page 372)

15-30 August 2003 Access Navigator - Release 1.8
Diagnostics & Troubleshooting
DS1 Line Loopback
DS1 Line Loopback
Provides a line loopback to verify that the DS1 signal is reaching the Access Navigator’s Quad T1
Framer card. The line loopup command creates a connection inside the Line Interface Unit (LIU),
causing it to loop the DS1 receive (input) back to the transmit (output). See Figure 15-4.
Syntax: set ds1 line <loopdown|loopup>
Figure 15-4 DS1 Line Loopback
DS1 Payload Loopback
Provides a payload loopback to verify DS1 signal processing in the Quad T1 Framer card. The payload
loopup command creates a signal connection inside the framer, causing it to loop the received payload
data back into the framer, where the 24 DS0s are reframed as the DS1 transmit output. See Figure 15-5.
Syntax: set ds1 payload <loopdown|loopup>
Figure 15-5. DS1 Payload Loopback
DS1
Line
Interface
Unit
Framer
Quad T1 Framer Card
IN
OUT
Time Slot
Interchange
DS1
Line
Interface
Unit
Framer
Quad T1 Framer Card
IN
OUT
Time Slot
Interchange