ADTRAN 1202076L2 - Manual (Page 83)

Chapter 7. Test Menu
61202076L1-1 TSU 600 User Manual 7-3
Network Interface Loopbacks
Network interface loopbacks affect the entire T1 data stream. There are
two types of network loopbacks: line loopback and payload loopback.
Line loopback loops all of the received data back toward the network.
The transmitted data is the identical line code that was received, includ-
ing any bipolar violations or framing errors.
Payload loopback is similar to line loopback, except that the framing is
extracted from the received data and then regenerated for the transmit-
ted data.
Figure 7-2. Network Loopback Tests
Local Loopbck
There are three available choices for setting the local loopback:
Scroll to select a setting and record it by pressing Enter. The unit returns
to the previous menu level.
Name Description
Line On Activates the line loopback
Payload On Activates the payload loopback
No Loopback Deactivates the loopback
TSU 600
DS1
NI CSU
Payload Loopback
Line Loopback
Secondary
Interface