Subject: [Sip] Diversion interrogation

From: "Thomas Ackermann" <[email-masked]>
Date: Mon, 23 May 2005 16:21:36 +0200

Hi together,

I would like to display active call diversions on the phone's display.
To achieve that I must do what H323 calls 'interrogation'.
Is there an idea how to implement that with SIP?
Is there a dedicated RFC addressing that issue?
Is anybody already doing this?

Best regards,
Thomas

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email-masked] for questions on current sip
Use [email-masked] for new developments on the application of sip

---

From: "Dale Worley" <[email-masked]>
Date: Mon, 23 May 2005 13:41:27 -0400

> From: Thomas Ackermann

There are at least two ways that a call could be diverted to another
target -- during call setup, the phone could return a 302 response, or
later, the phone could send a REFER to the remote end.

In the latter case, monitoring the diversion is simple, as the remote end
will send refer event information telling the dialog identification of the
call from the remote end to the new recipient.  The phone could then do a
dialog event SUBSCRIBE to the new recipient and follow the progress of the
new dialog.

In the first case, it looks messier to monitor the dialog.  But the phone
knows the addresses it provided in the 302, and can do dialog event
SUBSCRIBEs to them.  It already knows the Call-Id to watch for, since it is
the same as in the INVITE that it responded 302 to.

Dale

---

From: [email-masked]
Date: Tue, 24 May 2005 17:03:29 +1000

Dale, Thomas,
      I agree with all that Dale said below but had a somewhat different
take on the question, Thomas - if you can advise if the response below
cover what you were after, If not can you clarify the query more.

      I took the phrase below "active call diversions" and the H.323
reference to be more about the profile for call forwarding supplemental
services (H.450.3) than of an end points *actual* diversions for a call
that is in progress. I will try to illustrate what I see as the difference.

      In H.450.3 allows an endpoint to activate call forwarding
supplemental services CFB, CFNR, CFU, it also allows interrogation of an
endpoint to determine current settings - i.e. state of a diversion service,
and if applicable what number is it to be deflected to.

      I don't think the above ability for interrogating these profile kind
of settings in SIP, because they are implemented in logic outside the
protocol. You can make these kind of settings on intelligent SIP phones say
via a local menu system, or provision a central hosting registrar/proxy
(B2BUA...)via web or other means but I don't know of a way to 'interrogate'
for these service profile settings via SIP ?. Off the top of my head could
it be done using caller-prefs or similar ?.

      Sorry if I am way off the mark, also please advise if this thread
should be moved to Implementors or other.

Regards, Wayne.

Dale

**********************************************************************
Any personal or sensitive information contained in this email and
attachments must be handled in accordance with the Victorian Information
Privacy Act 2000, the Health Records Act 2001 or the Privacy Act 1988
(Commonwealth), as applicable.

This email, including all attachments, is confidential.  If you are not the
intended recipient, you must not disclose, distribute, copy or use the
information contained in this email or attachments.  Any confidentiality or
privilege is not waived or lost because this email has been sent to you in
error.  If you have received it in error, please let us know by reply
email, delete it from your system and destroy any copies.
**********************************************************************