Excalibur ISX 5312, Руководство по эксплуатации

Страница: 192 / 228

Excalibur ISX 5312/5314 T-1 Multiplexer Installation and Operation
6-2
Excalibur
ISX 5312/5314
ISDN TA
or Modem
Router
HUB
Port 1
Ethernet Ethernet
Port 2
*
Figure 6-1. Management via the Second Router WAN Port
• For leased-line circuits, the ISX 5312/5314 offers end-to-end diagnostics utilizing
the PN127 Digital Loop Test and the QRSS test pattern generator. If a failure
occurs with the remote router, the circuit can be debugged using this feature.
T-1 Line Pattern Test
You can verify the operation of a T-1 line by running a Pattern Test. During this test, the
ISX 5312/5314 generates a QRSS test pattern through the DS1 datastream at the internal
TDM bus. (See Figure 6-2.) The ISX 5312/5314 monitors for an incoming test pattern
and reports any errors up to 999 maximum. Errors can be inserted and the error counter
can be reset from the ISX 5312/5314's front panel.
Notes: This test interrupts T7 in both the transmit and receive directions.
When first initialized and following a T-1 line interruption, this test may take up to
30 seconds to synchronize up on the pattern.
To run this test, a loopback must be active somewhere in the Telco network, or the
remote unit must be in either a loopback condition or running a T-1 Line Pattern Test.
Caution: Do not run this test on an ISX 5312/5314 that is configured to initiate a dial
backup connection if it detects an LRC alarm. (See “Trigger” in Chapter 5.) If you do,
the ISX 5312/5314 will initiate a dial backup connection, because the test pattern
overwrites the LRC heartbeat message, causing an LRC alarm.