Paradyne COMSPHERE 3610, Operator'S Manual

Page: 102 / 310

COMSPHERE 3600 Series Data Service Units
4-22 July 1999 3610-A2-GB91-90
Digital Test
Digital Test (DT) is used to check the functionality of a
pair of DSUs and the data circuit between them.
The Digital Test uses the local DSU’s test pattern
generator. In a multipoint network (where only a control
DSU can originate a Digital Test), tributary DSUs not
involved in the test are placed in Test mode for the
duration of the test.
The local DSU transmits the 511-bit test pattern over
the network to the remote DSU for an operator-specified
length of time. The remote DSU receives the test pattern
and loops it back to its transmitter before the DTE
interface, and returns it to the local DSU, where the test
pattern is passed to the DSU’s comparator to be checked
for errors (Figure 4-9). At the conclusion of the test, the
local DSU releases the remote DSU from Digital
Loopback.
The Digital Test is session-disruptive except when a
dial backup session is active and is used to determine
whether a control DSU, a single tributary, and the network
between them are functioning properly. This test requires
the network connection to both DSUs. However, DTE
connections to the DSUs are not required.
NOTE
A control DSU can originate a
Digital Test in a point-to-point or
multipoint network, whereas a
tributary DSU can originate a
Digital Test in a point-to-point
network only, provided the
configuration option Respond to
Remote Digital Loopback
(RespondRDL) is enabled in the
control.
To access the Digital Test from the top-level menu,
make the following selections:
•
Local (F1)
•
Test
•
DSU (select active core)
•
DT
Figure 4-9. Digital Test