Alternative Routing Parameters

The alternative routing parameters are described in the table below.

Alternative Routing Parameters

Parameter

Description

'3xx Use Alt Route Reasons'

configure voip > sip-definition settings > 3xx-use-alt-route

[UseAltRouteReasonsFor3xx]

Defines the handling of received SIP 3xx responses regarding call redirection to listed contacts in the Contact header.

[0] No = (Default) Upon receipt of a 3xx response, the device tries each contact, one by one, listed in the Contact headers, until a successful destination is found. However, if a contact responds with a 486 or 600, the device doesn't try to redirect the call to next contact, and drops the call.
[1] No if 6xx = Upon receipt of a 3xx response, the device tries each contact, one by one, listed in the Contact headers. However, if a 6xx Global Failure response is received during this process (e.g., 600 Busy Everywhere) the device doesn't try to redirect the call to the next contact, and drops the call.
[2] Yes = Upon receipt of a 3xx response, the device redirects the call to the first contact listed in the Contact header. If the contact responds with a SIP response that is defined in the Reasons for Tel-to-IP Alternative Routing table, the device tries to redirect the call to the next contact, and so on. If a contact responds with a response that is not configured in the table, the device doesn't try to redirect the call to the next contact, and drops the call.

'Redundant Routing Mode'

configure voip > gateway routing settings > redundant-routing-m

[RedundantRoutingMode]

Determines the type of redundant routing mechanism when a call can’t be completed using the main route.

[0] Disable = No redundant routing is used. If the call can’t be completed using the main route (using the active Proxy or the first matching rule in the Routing table), the call is disconnected.
[1] Routing Table = (Default) Routing table is used to locate a redundant route.
[2] Proxy = Proxy list is used to locate a redundant route.

Note: To implement the Redundant Routing Mode mechanism, you first need to configure the parameter [AltRouteCauseTEL2IP] (Reasons for Alternative Routing table), as described in Alternative Tel-to-IP Routing Based on SIP Responses.

'Disconnect Call With PI If Alt'

[DisconnectCallwithPIifAlt]

Defines when the device sends the IP-to-Tel call to an alternative route (if configured) when it receives an ISDN Q.931 Disconnect message from the Tel side.

[0] Disable = (Default) The device forwards early media to the IP side if Disconnect includes PI, and disconnects the call when a Release message is received. Only after the call is disconnected does the device send the call to an alternative route.
[1] Enable = The device immediately sends the call to the alternative route.

For more information, see Alternative Routing upon ISDN Disconnect.

Note: The parameter is applicable only to digital interfaces.

configure voip > gateway manipulation settings > alt-map-tel-to-ip

[EnableAltMapTel2IP]

Enables different Tel-to-IP destination number manipulation rules per routing rule when several (up to three) Tel-to-IP routing rules are defined and if alternative routing using release causes is used. For example, if an INVITE message for a Tel-to-IP call is returned with a SIP 404 Not Found response, the call can be re-sent to a different destination number, configured by the [NumberMapTel2IP] parameter.

[0] = Disable (default)
[1] = Enable