AudioCodes Mediant 3000, User Manual

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User's Manual 250 Document #: LTRT-89729
Mediant 3000
17.4 Configuring SIP Message Manipulation
The Message Manipulations page allows you to define up to 100 SIP message
manipulation rules. Each manipulation rule can be assigned any Manipulation Set ID (0 to
19), enabling you to create groups (sets) of manipulation rules whereby rules of a group
are configured with the same Manipulation Set ID number. To use these Manipulation Sets,
you need to assign them to IP Groups in the IP Group table (see 'Configuring IP Groups'
on page
230 ) where they can be applied to inbound and/or outbound SIP messages.
SIP message manipulation enables the normalization of SIP messaging fields between
communicating network segments. For example, it allows service providers to design their
own policies on the SIP messaging fields that must be present before a SIP call enters
their network. Similarly, enterprises and small businesses may have policies for the
information that can enter or leave their networks for policy or security reasons from a
service provider. The manipulations can also be implemented to resolve incompatibilities
between SIP devices inside the enterprise network.
SIP message manipulation supports the following:

Addition of new headers.

Removal of headers ("Black list").

Modification of header components - value, header value (e.g., URI value of the P-
Asserted-Identity header can be copied to the From header), call's parameter values.

Deletion of SIP body (e.g., if a message body isn’t supported at the destination
network this body is removed).

Translating one SIP response code to another.

Topology hiding (generally present in SIP headers such as Via, Record Route, Route
and Service-Route).

Configurable identity hiding (information related to identity of subscribers for example,
P-Asserted-Identity, Referred-By, Identity and Identity-Info).

Apply conditions per rule - the condition can be on parts of the message or call’s
parameters.

Multiple manipulation rules on the same SIP message.
The manipulation is performed on SIP messages according to the Classification table
(source/destination of username/host prefixes, and source IP address). The manipulation
can be performed on message type (Method, Request/Response, and Response type) and
multiple manipulation rules can be configured for the same SIP message.
For the Gateway / IP-to-IP application, manipulation rules can be assigned as follows:

Manipulating inbound SIP INVITE messages: The Manipulation Set ID is selected
using the "global" parameter, GWInboundManipulationSet. If this parameter is not
configured, then no manipulation is done.

Manipulating outbound SIP INVITE messages: The Manipulation Set ID is selected
using the following logic:
a. According to the settings of the 'Outbound Message Manipulation Set' parameter
configured for the destination IP Group (in the IP Group table). In other words,
manipulation can be done per destination IP Group. If this parameter is not
configured, see below.
b. According to the settings of the "global" parameter,
GWOutboundManipulationSet. If this parameter is not configured, no
manipulation is done.