AudioCodes Mediant 500L User Manual page 1079

User's Manual
Parameter
Enable GRUU
configure voip > sbc settings
> enable-gruu
[EnableGRUU]
Version 7.2
the 'tgrp/trunk-context' parameters. The 'dtg' parameter appears in the
INVITE Request-URI (and in the To header).
For example, the received SIP message below routes the call to Trunk
Group ID 56:
INVITE sip:123456@192.168.1.2;dtg=56;user=phone SIP/2.0
Note: If the Trunk Group is not found based on the 'dtg' parameter, the
IP-to-Tel Routing table is used instead for routing the call to the
appropriate Trunk Group.
Determines whether the Globally Routable User Agent URIs (GRUU)
mechanism is used, according to RFC 5627. This is used for obtaining
a GRUU from a registrar and for communicating a GRUU to a peer
within a dialog.

[0] Disable (default)

[1] Enable
A GRUU is a SIP URI that routes to an instance-specific UA and can
be reachable from anywhere. There are a number of contexts in which
it is desirable to have an identifier that addresses a single UA (using
GRUU) rather than the group of UA's indicated by an Address of
Record (AOR). For example, in call transfer where user A is talking to
user B, and user A wants to transfer the call to user C. User A sends a
REFER to user C:
REFER sip:C@domain.com SIP/2.0
From: sip:A@domain.com;tag=99asd
To: sip:C@domain.com
Refer-To: (URI that identifies B's UA)
The Refer-To header needs to contain a URI that user C can use to
place a call to user B. This call needs to route to the specific UA
instance that user B is using to talk to user A. User B should provide
user A with a URI that has to be usable by anyone. It needs to be a
GRUU.

Obtaining a GRUU: The mechanism for obtaining a GRUU is
through registrations. A UA can obtain a GRUU by generating a
REGISTER request containing a Supported header field with the
value "gruu". The UA includes a "+sip.instance" Contact header
parameter of each contact for which the GRUU is desired. This
Contact parameter contains a globally unique ID that identifies the
UA instance. The global unique ID is created from one of the
following:

If the REGISTER is per the device's client (endpoint), it is the
MAC address concatenated with the phone number of the
client.

If the REGISTER is per device, it is the MAC address only.

When using TP, "User Info" can be used for registering per
endpoint. Thus, each endpoint can get a unique id – its phone
number. The globally unique ID in TP is the MAC address
concatenated with the phone number of the endpoint.
If the remote server doesn't support GRUU, it ignores the parameters
of the GRUU. Otherwise, if the remote side also supports GRUU, the
REGISTER responses contain the "gruu" parameter in each Contact
header. The parameter contains a SIP or SIPS URI that represents a
GRUU corresponding to the UA instance that registered the contact.
The server provides the same GRUU for the same AOR and instance-
1079
69. Configuration Parameters Reference
Description
Mediant 500L Gateway & E-SBC