3Com VCX v7111 User Manual page 126

Reasons for Alternative Routing
The Reasons for Alternative Routing screen includes two tables (Tel IP and IP Tel). Each
table enables you to define up to 4 different release reasons. If a call is released as a result
of one of these reasons, the gateway tries to find an alternative route to that call. The release
reason for IP Tel calls is provided in Q.931 notation. The release reason for Tel IP calls is
provided in SIP 4xx, 5xx and 6xx response codes. For Tel IP calls an alternative IP
address, for IP Tel calls an alternative hunt group.
See Tel to IP Routing Table
Hunt Group Routing for information on defining an alternative hunt group.
You can use this table for example:
For Tel IP calls, when there is no response to an INVITE message (after INVITE
retransmissions), and the gateway then issues an internal 408 No Response implicit
release reason.
For IP Tel calls, when the destination is busy, and release reason #17 is issued or for
other call releases that issue the default release reason (#3). See DefaultReleaseCause
in Table 23.
The reasons for alternative routing option for Tel IP calls, only applies when Proxy
Is not used.
To configure the reasons for alternative routing:
Open the Reasons for Alternative Routing screen (Protocol Management menu >
1
Routing Tables submenu > Reasons for Alternative Routing option); the Reasons for
Alternative Routing screen is displayed.
Reasons for Alternative Routing Screen
Figure 41
In the IP to Tel Reasons table, from the drop-down list select up to 4 different call failure
2
reasons that invoke an alternative IP to Tel routing.
126
for information on defining an alternative IP address. See
3Com
®
VCX V7111 VoIP Gateway User Guide
IP to