Figure 39 T1 Tab on the Units screen
Clock
The
Clock
needs to be set to where one end is providing timing (normally the PSTN) while the
other end is deriving clock from it (usually the CPE). The
Internal
clock setting is used when the
TSP acts as the PSTN and provides the clocking to the equipment under test.
External
Clock is
used when the TSP acts as the CPE and clocks from the equipment under test (i.e., if the TSP is
set for Internal clock, the equipment under test should be set for External clock, and vice versa).
Note:
If using only one port on a Dual T1/E1 that is configured for External Clock, port 2 must be used
and will derive its clock from the equipment under test. If using both ports, the device connected
to Port 1 must use the same clocking reference as the device connected to port 2.
Framing
For
Framing
, both ends need to match otherwise synchronization will not be achieved. D4 is
considered a legacy format while ESF (extended superframe) has more features available such
as CRC-4 for detection of errors without interrupting the signal.
Line Coding
For Line Coding,
AMI
suffices if no DDS data exists on any of the T1 channels.
B8ZS
is used
when DDS data channels are present to compensate for when an all Zeros state exist (when
equipment is off) which can lead to lost of synchronization on the T1 due to too many successive
zeros.
Telecom Simulation Platform
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