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Cisco VISM Installation and Configuration Guide
Release 3.0, Part Number OL-2521-01 Rev. D0, June 2004
Chapter3 VISM Functional Descriptio n
Call Control Function
xGCP Extensions for AAL2 Switched PVC and AAL2 SVC Operating Modes
VISM supports the following extensions to the xGCP protocols for AAL2 switched and A AL2 SVC
applications:
A new AAL2 Type 3 message type (coded ‘010001’) for telephone signal events (TSEs). The
following are TSEs:
ECAN off
Request audible ring tone
Ack continuity test
Request stop audible tone
Request continuity test
An extended naming structure to include ATM endpoints. An ATM endpoint enables the following
to be included in the definition of an endpoint:
ATM address
virtual path identifier (VPI)
VCI
VCCI
CID
An extended list of connection events in MGCP, known as an ATM Package. These events are:
Setup complete (for AAL2 CID path)
Setup failed (for AAL2 CID path)
Enable CAS via type 3 packets
Introduction of a Profile Type in call setup commands to describe encoding techniq ues.
Endpoint Service States
Endpoints exist in one of two service states—in-service (IS) and out-of-service (OOS). The state of an
endpoint is determined by user configuration commands and line alarm conditions. When an endpoint is
added, it automatically assumes the state of the line.
When endpoints are taken OOS, the transition can be graceful or forced. If graceful, no new connections
are permitted while ongoing connections are allowed to terminate normally. If forced, no new
connections are permitted and all ongoing connections ar e t ermi na te d im medi ate ly.
You can also bring an endpoint to the IS and OOS states with the following commands, which operate
either on a line-by-line basis or on the entire VISM card:
cnflnis—Configure a line as IS
cnflnoos—Configure a line as OOS
cnfgwis—Configure a VISM card as IS
cnfgwoos—Configure a VISM card as OOS
These commands allow you to specify either a graceful or forced transition.