ADTRAN TSU 120, Руководство пользователя

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Chapter 1. Introduction
20
TSU 120 User Manual 61200.129L1-1
TSU 120
Network Interface
(NI)
(Controller)
T 1
DSX-1 Interface
DSX-1 PBX
PORT LINE
LOOPBACKS
Figure 1-12
Diagram of Loopbacks
Pattern Generation
The TSU 120 offers two available test Patterns: QRSS
and 511.
QRSS Pattern
The QRSS pattern is commonly used to simulate real
data in T1 interfaces. This pattern can be assigned to
appear in all DS0s or only in TST DS0s. When QRSS is
set in all DS0s and one of the network loopbacks
previously described is activated at the far end, a total
end-to-end integrity check can be run without the
need for any external test equipment. When QRSS is
assigned to TST DS0s, an integrity check of the link
can be run along with normal data flow. The TST
DS0s are user assigned as part of the DS0 Map.
511 Pattern
The 511 pattern is generated and checked by the
Nx56/64 serial interface. It only appears in the DS0s
assigned to the Nx56/64 port which is generating the
pattern. When used in conjunction with the port
loopback at the far end as previously described, an
end-to-end integrity check can be made on the DTE
ports.