Interworking Sip Refer Messages - AudioCodes Mediant 4000 SBC User Manual

CHAPTER 22 SBC Overview
Parameter
Value
'Diversion
Header Mode'
= Add
'History-Info
Header Mode'
= As Is
'Diversion
Header Mode'
= As Is
'History-Info
Header Mode'
= Add
'Diversion
Header Mode'
= Add
'History-Info
Header Mode'
= Remove
'Diversion
Header Mode'
= Remove
'History-Info
Header Mode'
= Add
'Diversion
Header Mode'
= Remove
'History-Info
Header Mode'
= Remove

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
■ Advanced routing rules for the new, initiated INVITE
■ Forwarding early media after REFER while attempting to avoid transcoding (by sending
session update)
■ Interoperate with environments were different SIP UAs lack basic SIP functionality such as re-
INVITE, UPDATE, PRACK, Delayed Offer, re-INVITE without SDP
■ Session updates after connect to avoid transcoding
SIP Header Present
in incoming SIP
Message
Not Present
present
Present Not
present
Not Present
present
Present Not
present
Present Present
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Mediant 4000 SBC | User's Manual
Device Action
Diversion added from
History-Info
History-Info added from
Diversion
Diversion added from
History-Info
History-Info removed
History-Info added from
Diversion
Diversion removed
Both removed
IP Header Present
in outgoing SIP
Message
Present Present
Present Present
Present Not
present
Not Present
present
Not Not
present present