Avaya 03-300430 User Manual

This MO was formerly known as “ISDN-LNK (ISDN-PRI Signaling Link Port)”. For related 
information, see 

Note:

See the figures in the 

section of this chapter for an illustration of the principles described below.

The ISDN-PRI interface uses out-of-band signaling (as opposed to robbed-bit, in-band 
signaling) to transmit control messages between two endpoints. User information channels 
carry digitized voice and digital data and are known as bearer channels (B channels). B 
channels are assigned to DS1 ISDN trunks or PRI endpoints. Call-control signaling for the B 
channels is combined and carried over the separate ISDN-PRI Signaling Link Port D channel.
The ISDN-PRI Signaling Link Port (ISDN-LNK) is a port on a TN464C or higher suffix UDS1 
Interface circuit pack that has a direct interface to the packet bus that carries D-channel 
messages to the processor. The associated B channels can use ports on the same circuit pack 
or ports on other TN464C or higher suffix or TN767 DS1 Interface circuit packs. (The TN722 
cannot be used for this application). The B channels are connected to the TDM Bus.

Note:

 / 

: Although the ISDN-PLK MO is provided for a G700 media gateway, 

this MO only partially supports the G700’s MM710 DS1 media module.

Two types of DS1 interfaces exist:

●

24 DS0 channels on a 1.544-Mbps link

●

31 DS0 channels + 1 framing channel on a 2.048-Mbps link

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 on the 
TN464F/GP circuit pack. In certain configurations (NFAS), the 16th port may be used as a 
B-channel. Refer to 

on page 1429 for further details.

The TN767 DS1 interface is used for 24 channel 1.544 Mbps systems. The TN464F/GP can be 
used for either 24 or 32 channel systems. The 32-channel (31 DS0 channels + 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.

1. For this MO, location is 24 for 24-channel interfaces and 16 for 32-channel interfaces.

ISDN-LNK

MIN

test port location l

ISDN-PRI Signaling Link port

ISDN-LNK

WRN

test port location sh

ISDN-PRI Signaling Link port