AudioCodes E-SBC User Manual

CHAPTER30 SBC Overview
Mediant 1000 Gateway & E-SBC | User's Manual
Local Handling of SIP 3xx
The device can handle SIP 3xx responses on behalf of the dialog-initiating UA and retry the request
(e.g., INVITE) using one or more alternative URIs included in the 3xx response. The new request
includes SIP headers from the initial request such as Diversion, History-Info, P-Asserted-Id, and
Priority. The source and destination URIs can be manipulated using the regular manipulation
mechanism.
The device sends the new request to the alternative destination according to the IP-to-IP Routing
table rules. (where the 'Call Trigger' field is set to 3xx). It is also possible to specify the IP Group
that sent the 3xx request as matching criteria for the re-routing rule in this table ('ReRoute IP Group
ID' field).
Interworking SIP Diversion and History-Info Headers
This device can be configured to interwork between the SIP Diversion and History-Info headers.
This is important, for example, to networks that support the Diversion header but not the History-
Info header, or vice versa. Therefore, mapping between these headers is crucial for preserving the
information in the SIP dialog regarding how and why (e.g., call redirection) the call arrived at a
certain SIP UA. If the Diversion header is used, you can specify the URI type (e.g., "tel:") to use in
the header, using the SBCDiversionUriType parameter.
This feature is configured in the IP Profiles table using the following parameters:
■ 'Diversion Header Mode' (IPProfile_SBCDiversionMode) - defines the device's handling of the
Diversion header
■ 'History-Info Header Mode' (IPProfile_SBCHistoryInfoMode - defines the device’s handling of
the History-Info header
The handling of the SIP Diversion and History-Info headers is described in the table below:
Table 30-1: Handling of SIP Diversion and History-Info Headers
Parameter
Value
SIP Header Present
in incoming SIP
Message
Device Action
IP Header Present
in outgoing SIP
Message
Diversion History-
Info
Diversion History-
Info
'Diversion
Header Mode'
= Add
'History-Info
Header Mode'
= Add
Not
present
Present Diversion added from
History-Info
Present Present
'Diversion
Header Mode'
= Add
'History-Info
Header Mode'
= Add
Present Not
present
History-Info added from
Diversion
Present Present
'Diversion
Header Mode'
= Add
Present Present Diversion replaced and
added from History-Info
History-Info replaced and
added from Diversion
Present Present
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AudioCodes E-SBC Specifications

General

Brand	AudioCodes
Model	E-SBC
Category	Gateway
Language	English