100
Primary to Basic Rate ISDN Multiplexer
SALES: 0118 965 5100
Terminal will not make or answer a call.
If the P light stays off see the section on "Terminal will not activate at layer 1". If the P light
flashes check that there are not too many terminals on the line. For basic rate, the maximum
is 8 (1 for point-to-point) and for primary rate, the maximum is 1.
For a basic rate port, check that the BRI Setup is correct in Software Setup. This should be
point-to-point, if it is a point-to-point terminal expecting TEI=0. Otherwise, it should be point
to multipoint, which allows automatic TEI assignment.
If the P light fails to light, the terminal may be faulty.
Now check that there are channels enabled on that port and that there are sufficient channels
enabled on PRI 1, i.e. check Channel Setup is correct in Software Setup.
If ETSI protocol is set and routing mode is set to channel check that a route to PRI 1 has been
set up.
Check that the terminal is compatible with the network. For example, if using an ETSI
network the terminals should be ETSI compliant. Other terminals may not function due to
protocol errors.
For BRI TA's being used with National ISDN protocol, check that the correct SPID has been
entered in the TA. This should consist of the number for the TA (in Number Setup) + 0101.
NB: if BRI Require SPID in Software Setup is set to “No” the The Primary to Basic Rate
ISDN Multiplexer will allow calls to made without a correct SPID but the TA may block the
call itself.
Use the protocol analyser to display the layer 3 messages. The called terminal may send
DISCONNECT, RELEASE or RELEASE COMPLETE with a cause value indicating the
problem.
A potential problem may be that called terminal and calling terminal do not support the same
bearer capability, in which case the called terminal will send RELEASE COMPLETE with a
cause "Incompatible Destination". Another possibility is that the called terminal is expecting
a Called Party Number or Calling Party Number information element in the SETUP message.
These are optional services from the network.
Incoming calls are rejected or not routed correctly
If the B light on the called port switches on but the P light stays off see the section on
"Terminal will not activate at layer 1".
For a basic rate port check that the BRI Setup is correct in Software Setup. This should be
point-to-point, if it is a point-to-point terminal expecting TEI=0. Otherwise, it should be point
to multipoint which uses the global TEI (127).
