Avaya 03-300430 User Manual

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Communication Manager Maintenance-Object Repair Procedures
1774 Maintenance Procedures for Avaya Communication Manager 3.0, Media Gateways and Servers
 
Multiple PRI endpoints on one line-side facility are separate and distinct within the facility. 
Non-overlapping contiguous sets of B channels are associated with each PRI endpoint, and the 
endpoint equipment is expected to initiate calls within these boundaries. The endpoint 
application equipment must:
Use standard ISDN-PRI signaling
Adhere to the administered PRI endpoint boundaries when initiating calls
Handle incoming calls appropriately, based on the originating PRI endpoint
Signaling and B-Channel States
PRI ports use a separate channel called the D channel for call-control and signaling messages. 
This is called out-of-band signaling. The D channel associated with the set of B channels is an 
ISDN-PRI signaling link’s port (ISDN-LNK). The signaling protocol used on the ISDN-PRI 
signaling-link port’s D channel is defined by one of the four selectable ISDN-PRI Specifications: 
Avaya, CCITT, ECMA, and ANSI.
The ISDN-PRI Specification defines the possible service states for a B channel. The service 
state is negotiated with the far-end terminal adapter, changes over time, and can have far- and 
near-end components. The service state is initialized to Out-Of-Service/Far-End, and an 
attempt is made to negotiate it to In-Service. Use status pri-endpoint extension to 
display the service state of a particular PRI endpoint port’s B channel.
If a call is present, the Specification defines the permissible call states as well. There are tests in 
the short and long test sequences for the PRI endpoint port designed to audit these states and 
ensure agreement between both ends of the PRI wideband connection.
Alarming Based on Service States
A PRI endpoint port’s B channel logs a warning alarm when it is placed in a Maintenance/
Far-End or Out-Of-Service/Far-End state. While in such a state, the port is unusable for calls to 
the terminal adapter. However, the user can still use the other remaining ports in the PRI 
endpoint to make calls to and from the terminal adapter. When a warning alarm is raised, use 
status pri-endpoint extension to determine the exact state of the port. Other alarms 
can be diagnosed by using the short and long test sequences. Note that a PRI endpoint port’s B 
channel can be placed in a far-end service state by direct action by the far-end terminal adapter 
or by inaction of the far-end terminal adapter. For example, if it does not respond to a Remote 
Layer 3 Query (see Test #260 for ISDN-LNK) the associated PRI endpoint port’s B channels will 
be placed in the Maintenance/Far-End service state.
A PRI endpoint port is a port on a UDS1 interface circuit pack and thus depends on the health of 
the circuit pack for proper operation (see the following figure). A problem on the associated 
ISDN-LNK’s (ISDN-PRI signaling-link port’s) D channel can also affect the PRI endpoint. In turn, 
the ISDN-LNK depends on the SYS-LINK (system link) to the packet interface. Keep this 
hierarchy of dependencies in mind when diagnosing problems.