AudioCodes E-SBC User Manual

CHAPTER19 Coders and Profiles
Mediant 1000 Gateway & E-SBC | User's Manual
Parameter Description
a. Before forwarding the REFER request, the device
changes the host part to the device's IP address
and adds a special prefix ("T~&R_") to the Contact
user part.
b. The incoming INVITE is identified as a REFER-res-
ultant INVITE according to this special prefix.
c. The device replaces the host part in the Request-
URI with the host from the REFER contact. The
special prefix remains in the user part for regular
classification, manipulation, and routing. The spe-
cial prefix can also be used for specific routing
rules for REFER-resultant INVITEs.
d. The special prefix is removed before the resultant
INVITE is sent to the destination ((transfer target).
■ [2] IP Group Name = Changes the host part in the
REFER message to the name configured for the IP
Group (in the IP Groups table).
■ [3] Handle Locally = Handles the incoming REFER
request itself without forwarding the REFER. The
device generates a new INVITE to the alternative
destination (transfer target) according to the rules in the
IP-to-IP Routing table (the 'Call Trigger' parameter
must be set to REFER).
■ [4] Local Host = In the REFER message received
from the transferor, the device replaces the Refer-To
header value (URL) with the IP address of the device or
with the ‘Local Host Name’ parameter value configured
for the IP Group (transferee) to where the device
forwards the REFER message. This ensures that the
transferee sends the re-routed INVITE back to the
device which then sends the call to the transfer target.
■ [5] Keep URI (user@host) = The device forwards the
REFER message without changing the URI
(user@host) in the SIP Refer-To header. If you
configure the 'Remote Replaces Mode' parameter (see
below) to any value other than Keep as is, the
devicemay modify the 'replaces' parameter of the
Refer-To header to reflect the call identifiers of the leg.
This applies to all types of call transfers (e.g., blind and
attendant transfer).
Note:
■ You can override the parameter's settings using
Message Manipulation rules configured with the
AudioCodes proprietary SIP header, X-AC-Action. For
more information, see Using the Proprietary SIP X-AC-
Action Header on page815.
■ The corresponding global parameter is
[SBCReferBehavior].
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AudioCodes E-SBC Specifications

General

Brand	AudioCodes
Model	E-SBC
Category	Gateway
Language	English