Alternative Routing For Tel-To-Ip Calls; Alternative Routing Based On Ip Connectivity - AudioCodes Mediant 1000B User Manual

You can view the connectivity status of IP destinations in the following Web interface
pages:

Tel-to-IP Routing table: The connectivity status of the IP destination per routing rule
is displayed in the 'Status' column. For more information, see 'Configuring Tel-to-IP
Routing Rules' on page 483.

IP Connectivity: This page displays a more informative connectivity status of the IP
destinations used in Tel-to-IP routing rules in the Tel-to-IP Routing table. For viewing
this page, see 'Viewing IP Connectivity' on page 797.
24.6

Alternative Routing for Tel-to-IP Calls

The device supports various alternative Tel-to-IP call routing methods, as described in this
section.

24.6.1 Alternative Routing Based on IP Connectivity

You can configure the device to route Tel-to-IP calls to an alternative IP destination when
the connectivity state of an IP destination is unavailable. The alternative routing rules are
configured in the Tel-to-IP Routing table. These rules must be configured anywhere below
the "main" routing rule and with identical matching characteristics (e.g., destination prefix
number) to the "main" routing rule. The device uses the first alternative route that is
available. For more information on configuring alternative Tel-to-IP routing rules in the Tel-
to-IP Routing table, see 'Configuring Tel-to-IP Routing Rules' on page 483.
Note:
server is not used.
The device searches for an alternative routing rule (IP destination) when any of the
following connectivity states are detected with the IP destination of the "main" routing rule:

No response received from SIP OPTIONS messages. This depends on the chosen
method for checking IP connectivity.

Poor QoS according to the configured thresholds for packet loss and delay.
Unresolved DNS, if the configured IP destination is a domain name (or FQDN). If the
domain name is resolved into two IP addresses, the timeout for INVITE re-transmissions
can be configured using the HotSwapRtx parameter. For example, if the parameter is
configured to 3 and the device receives no response upon its initial INVITE message to the
first IP address, it attempts up to three times to route the call to the first IP address and if
unsuccessful, it attempts to re-route the call to the second resolved IP address.
The connectivity status of the IP destination is displayed in the 'Status' column of the Tel-
to-IP Routing table per routing rule. If it displays a status other than "ok", the device
considers the IP destination as unavailable and attempts to re-route the call to an
alternative destination. For more information on the IP connectivity methods and on
viewing IP connectivity status, see 'IP Destinations Connectivity Feature' on page 501.
The table below shows an example of alternative routing where the device uses an
available alternative routing rule in the Tel-to-IP Routing table to re-route the initial Tel-to-IP
call.
User's Manual
Alternative routing based on IP connectivity is applicable only when a proxy
Mediant 1000B Gateway and E- SBC
502 Document #: LTRT-27044