User manual

Product Description
Tests and Loopbacks
2-32 July 2004 Wide Bank 28 DS3 - Release 2.4
Low-Speed Performance Monitoring
The low-speed transceivers continuously monitor the incoming physical DS1 or E1 line quality for
Excess Zeros, Loss of Signal, and Bipolar Violations.
LS Alarm Signals
 Loss Of Signal.
 Hardware Failure.
 Far-End DS1 (or E1) Loss of Signal.
 Line Code Violations
DS3 Loopback Modes
NOTE: For details on how to run DS3 loopback tests, see Testing the DS3 Near-End
with Loopback Tests on page 7-35.
DS3 Line Loopback
DS3 Line Loopback returns the received DS3 signal from the transceiver back to the transceiver
output, without being processed by the M13 framer.
Figure 2-14 DS3 Line Loopback
Loopback
Relays
Trans-
ceiver
Selector
M13
Framer
Trans-
ceiver
Relays
LS Card HS Card
Toward DS3
DS1/E1 DS3
Send AIS
Toward DS1/E1