ADTRAN 1200410L2, User Manual

Page: 58 / 80

Chapter 7. Test Menu
58 ESU LT User Manual 61200410L2-1A
Network Tests
Network tests are used to control the activation of loopbacks and the
initiation of data test patterns.
The network tests are run on the network interface. Three different
test configurations can be selected to determine the type of loopback
and the pattern to run. Test results are displayed in the LCD window.
See Figure 7-2.
Figure 7-2. Local Loopback Screen
Loopback Tests
A number of different loopbacks can be invoked locally from the
front panel, by T-Watch commands, or remotely by using special in-
band codes (AT&T D4 network loop-up and loopdown codes).
Additionally, the loopbacks can be remotely controlled by means of
out-of-band commands by the E1 ESF FDL or from T-Watch PRO
via a modem connection.
Network Interface Loopbacks
Network interface loopbacks affect the entire E1 data stream (see
Figure 7-3 on page 59). The two types of network loopbacks are
described below.
Line Loopback
Loops all of the received data back toward the network. The
transmitted data is the identical line code that was received, including
any bipolar violations or framing errors.
Payload Loopback
Similar to line loopback, except that the framing is extracted from the
received data and then regenerated for the transmitted data.