AudioCodes Mediant 3000, User Manual

Page: 357 / 872

Version 6.6 357 Mediant 3000
User's Manual 24. Routing
Notes: When using a proxy server, you do not need to configure this table, unless
you require one of the following:
•
Fallback (alternative) routing if communication is lost with the proxy
server.
•
IP security, whereby the device routes only received calls whose source
IP addresses are defined in this table. IP security is enabled using the
SecureCallsFromIP parameter.
•
Filter Calls to IP feature: the device checks this table before a call is
routed to the proxy server. However, if the number is not allowed, i.e.,
the number does not exist in the table or a Call Restriction (see below)
routing rule is applied, the call is released.
•
Obtain different SIP URI host names (per called number).
•
Assign IP Profiles to calls.
•
For this table to take precedence over a proxy for routing calls, you need
to set the parameter PreferRouteTable to 1. The device checks the
'Destination IP Address' field in this table for a match with the outgoing
call; a proxy is used only if a match is not found.
In addition to basic outbound IP routing, this table supports the following features:

Least Cost Routing (LCR): If the LCR feature is enabled, the device searches the
routing table for matching routing rules and then selects the one with the lowest call
cost. The call cost of the routing rule is done by assigning it a Cost Group. For
configuring Cost Groups, see 'Least Cost Routing' on page
215 . If two routing rules
have identical costs, then the rule appearing higher up in the table (i.e., first-matched
rule) is used. If a selected route is unavailable, the device uses the next least-cost
routing rule. However, even if a matched rule is not assigned a Cost Group, the device
can select it as the preferred route over other matched routing rules with Cost Groups,
according to the settings of the LCR parameter, LCRDefaultCost (see 'Enabling LCR
and Configuring Default LCR' on page
217 ).

Call Forking: If the Tel-to-IP Call Forking feature is enabled, the device can send a
Tel call to multiple IP destinations. An incoming Tel call with multiple matched routing
rules (e.g., all with the same source prefix numbers) can be sent (forked) to multiple IP
destinations if the rules are defined with a Forking Group in the table. The call is
established with the first IP destination that answers the call.

Call Restriction: Rejects calls whose matching routing rule is configured with the
destination IP address of 0.0.0.0.

Always Use Routing Table: Even if a proxy server is used, the SIP Request-URI
host name in the outgoing INVITE message is obtained from this table. Using this
feature, you can assign a different SIP URI host name for different called and/or
calling numbers. This feature is enabled using the AlwaysUseRouteTable parameter.

IP Profiles: IP Profiles can be assigned to destination addresses (also when a proxy
is used).

Alternative Routing (when a proxy isn't used): An alternative IP destination can be
configured for a specific call. To associate an alternative IP address to a called
telephone number prefix, assign it with an additional entry with a different IP address,
or use an FQDN that resolves into two IP addresses. For more information on
alternative routing, see 'Alternative Routing for Tel-to-IP Calls' on page
368 .