Performing Loopback Tests; Response To Local Loopback Assertion; Performing A Loopback Test On The Isdn Port (43X, 53X, 44X And 54X); Prerequisites - 3Com NETBuilder SI Using Manual

Performing
Loopback Tests
Response to Local
Loopback Assertion
Performing a
Loopback Test on the
ISDN Port (43x, 53x,
44x and 54x)
This section describes the bridge/router response to a local loopback
assertion and how to perform a loopback diagnostic test on the WAN
and serial ports. It also describes the steps required to perform additional
types of loopback tests for a T1/FT1 module.
If the bridge/router is connected to a DTE that asserts a local loopback
signal, the bridge/router displays:
Path x Detected DTE Loopback ON, switching to echo mode
The bridge/router in echo mode transmits the received data back to
the DTE.
When the signal is removed, the bridge/router displays:
Path x Detected DTE Loopback OFF, switching to normal mode
This section describes how to perform a loopback test on the built-in
ISDN port on model 43x, 53x , 44x, and 54x bridge/routers.
Figure 9 shows the data flow that occurs when this loopback test is
performed. Both B channels occupy the same physical connector and no
TA is required in this configuration.
Figure 9 ISDN Loopback Testing
Both channels (B1 and B2)
occupy the same physical connector

Prerequisites

Before beginning this procedure, complete the following tasks:
Attach a console or Telnet to your SuperStack II bridge/router.
Configure the ISDN port according to "Configuring ISDN on the WAN
Port (43x, 44x, 53x, and 54x)" on page 70.

Performing Loopback Tests

Port 3
B1 (Path 3.1)
Port 4
B2 (Path 3.2)
133
ISDN