AudioCodes Mediant 4000 SBC User Manual page 351

User's Manual
Parameter
Type
type
[IPGroup_Type]
Version 7.2
the view.
For more information on the Topology view, see ''Building and Viewing
SIP Entities in Topology View'' on page 372.
Defines the type of IP Group:

[0] Server = Applicable when the destination address of the IP
Group (e.g., ITSP, Proxy, IP-PBX, or Application server) is known.
The address is configured by the Proxy Set that is associated with
the IP Group.

[1] User = Represents a group of users such as IP phones and
softphones where their location is dynamically obtained by the
device when REGISTER requests and responses traverse (or are
terminated) by the device. These users are considered remote (far-
end).
Typically, this IP Group is configured with a Serving IP Group that
represents an IP-PBX, Application or Proxy server that serves this
User-type IP Group. Each SIP request sent by a user of this IP
Group is proxied to the Serving IP Group. For registrations, the
device updates its registration database with the AOR and contacts
of the users.
Digest authentication using SIP 401/407 responses (if needed) is
performed by the Serving IP Group. The device forwards these
responses directly to the SIP users.
To route a call to a registered user, a rule must be configured in the
SBC IP-to-IP Routing table. The device searches the dynamic
database (by using the Request-URI) for an entry that matches a
registered AOR or Contact. Once an entry is found, the IP
destination is obtained from this entry and a SIP request is sent to
the destination.
The device also supports NAT traversal for the SIP clients located
behind NAT. In this case, the device must be defined with a global
IP address.

[2] Gateway = In scenarios where the device receives requests to
and from a gateway representing multiple users. This IP Group
type is necessary for any of the following scenarios:

The IP Group cannot be defined as a Server-type since its
address is initially unknown and therefore, a Proxy Set cannot
be configured for it.

The IP Group cannot be defined as a User-type since the SIP
Contact header of the incoming REGISTER does not represent
a specific user. The Request-URI user part can change and
therefore, the device is unable to identify an already registered
user and therefore, adds an additional record to the database.
The IP address of the Gateway-type IP Group is obtained
dynamically from the host part of the Contact header in the
REGISTER request received from the IP Group. Therefore, routing
to this IP Group is possible only once a REGISTER request is
received (i.e., IP Group is registered with the device). If a
REGISTER refresh request arrives, the device updates the new
location (i.e., IP address) of the IP Group. If the REGISTER fails,
no update is performed. If an UN-REGISTER request arrives, the
IP address associated with the IP Group is deleted and therefore,
351
Description
17. Control Network
Mediant 4000 SBC