MCS Ringback and Treatment Service
35
•
The application of audible ringback is terminated upon the reception of
any final response from the transfer-to target.
•
The SDP negotiation that enables the transfer-target to hear ringback
is achieved through the use of re-INVITEs from the MCS Session
Manager. It is possible that these are not seen by the transfer-target if
their discriminator has ’CODECCHANGE’ set to False. In this case they
are handled by an internal MCS mechanism.
Application of treatment service call flows
The following SIP interactions relate to treatment service call flows:
•
As the REFER is handled within the MCS, the final response for the
transfer-to INVITE is handled internally and a NOTIFY(sipfrag) is
generated and sent to the Personal Agent (PA).
•
The application of treatment is triggered when the NOTIFY(sipfrag) is
generated after the completion of the transfer attempt.
•
Network-based ringback may have been previously applied (although
unlikely); this is terminated on the reception of any final response from
the transfer-to target.
Note: This treatment service differs from the normal capabilities of
treatment service as are typically available. That is, even though it is
possible to provision a route to attempt after a treatment is complete
(for example, to an operator position), this route is not attempted for
treatments applied as a result of this service being activated.
Population of the SIP messaging for ringback service
The Universal Resource Indicator (URI) used to trigger the capability of the
ringback service on the MAS is important to the function of the service.
The following example describes the INVITE generated to trigger ringback
service on the MAS.
INVITE
sip:annc@sanity1.com;play=ringback;early=no;repeat=infinit
e;mediatype=t
reatment;locale=en_US SIP/2.0
t:
"annc"
<sip:annc@sanity1.com;play=ringback;early=no;repeat=infini
te;mediatype=
treatment;locale=en_US>
f:
"1207710011" <sip:1207710011@sanity1.com>;tag=2065309526
i:
fe7369081f4602d716e77b1a9a49f626ecf90c@47.104.23.220
CSeq:
11539 INVITE
v:
SIP/2.0/UDP
47.104.23.220:5060;branch=z9hG4bK4fd563a0cdd151b06e25395eb7
cd251f
Max-Forwards:
20
Nortel Media Application Server
Media Application Server Planning and Engineering
NN42020-201
01.04
Standard
4.0
27 July 2007
Copyright © 2007, Nortel Networks
.