Avaya Definity SI, Maintenance Manual, Page: 1728 / 2968

Maintenance Object Repair Procedures
555-233-123 10-942 Issue 4 May 2002
The TN767 DS1 interfaces is used for 24 channel 1.544 Mbps systems. The
TN464C or later can be used for either 24 or 32 channel systems. The 32-channel
(31 DS0 ch 1 framing channel on a 2.048 Mbps link) are only supported
on TN464 series circuit packs. A description of these circuit packs appears in
DS1-BD or UDS1-BD maintenance documentation.
In a 24 channel system, the DS1 ISDN Trunk or PRI endpoint port (B-channels)
may use any of the first 23 ports. The ISDN-PRI Signaling Link Port must be the
24th port. In certain configurations (NFAS), the 24th port may be used as a
B-channel. Refer to the ISDN-PRI Signaling Group (ISDN-SGR) Maintenance
documentation for further details.
In a 32 channel system, the DS1 ISDN Trunk or PRI endpoint port (B-channels)
may use any of the ports 1-15 or 17-31, but the ISDN-PRI Signaling Link Port
must be the 16th port. In certain configurations (NFAS), the 16th port may be used
as a B-channel. Refer to the ISDN-PRI Signaling Group (ISDN-SGR)
Maintenance documentation for further details.
ISDN-PLK handles maintenance and recovery for the D-channel port on the DS1
carrying the signaling link. A problem with the ISDN-PRI Signaling Link Port
(D-channel) has an effect on all of the associated DS1 ISDN Trunks or PRI
endpoint ports (B-channels) since no call control information can be conveyed to
the far-end switch or Terminal Adapter without it. Stable calls may remain
operational, but no new calls can be made.
The ISDN-PRI Signaling Link Port (ISDN-PLK) itself depends on two other
entities: the UDS1 interface circuit pack (TN464) it resides on, and the Packet bus
which provides the link to the processor. If there are problems with the ISDN-PLK,
also investigate the TN464 UDS1 interface circuit pack (UDS1-BD) and the
packet bus (PKT-BUS).