Interworking Sip Diversion And History-Info Headers; Interworking Sip Refer Messages - AudioCodes Mediant 4000 SBC User Manual

20.9.2 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 (IPProfile parameter) using the following
parameters:

SBCDiversionMode - defines the device's handling of the Diversion header

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 20-1: Handling of SIP Diversion and History-Info Headers
Parameter Value
HistoryInfoMode = Add
DiversionMode = Remove
HistoryInfoMode =
Remove
DiversionMode = Add
HistoryInfoMode =
Disable
DiversionMode = Add
HistoryInfoMode =
Disable
DiversionMode = Add
HistoryInfoMode = Add
DiversionMode = Add
HistoryInfoMode =
Remove
DiversionMode = Remove

20.9.3 Interworking SIP REFER Messages

The device supports interworking of SIP REFER messages. SIP UAs may support different
versions of the REFER standard while others may not even support REFER.
This feature supports the following:

Attended, unattended, and semi-attended call transfers

Sending INVITE, REFER-notifications, BYE, PRACK and Session Timer on behalf of
peer PBXs
User's Manual
SIP Header Present in Received SIP Message
Diversion History-Info
Diversion Not present
converted to
History-Info.
Diversion removed.
Not present. History-Info
converted to
Diversion.
History-Info
removed.
Diversion Not present.
converted to
History-Info.
Not present. History-Info
converted to
Diversion.
Diversion History-Info
converted to converted to
History-Info. Diversion.
Diversion removed. History-Info
removed.
440
Mediant 4000 SBC
Diversion and History-Info
Diversion removed.
History-Info added to Diversion.
History-Info removed.
Diversion added to History-Info.
History-Info added to Diversion.
Headers are synced and sent.
Both removed.
Document #: LTRT-41729