Subject: Re: [Sipping] Thoughts on the conf-info package

From: [email-masked]
Date: Fri, 24 May 2002 08:35:17 -0400

M. Hammer wrote:

>Does there need to be a mechanism by which party A can notify the party B
>in a 2-party call that no other parties are authorized to join?  Or should
>that be implicit?

Just for clariication, how would this new 'no conferece' feature interwork
with other features such as 'consultative transfer' or even 'call pick
up.'.

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From: Michael Hammer <[email-masked]>
Date: Fri, 24 May 2002 10:32:19 -0400

Tom,

The short answer would be re-INVITEs.

The long answer is that this hypothetical was intended to expose the 
assumption of a certain amount of privacy that one expects when making a 
phone call.

As others have pointed out, if the other party is intent on conferencing 
another into the call without your knowledge, it's almost impossible to 
prevent that.  Once, party B has your communication, there's nothing to 
stop them from relaying it elsewhere.

I was only asking for parity in the consideration to party A and party C in 
terms of protecting privacy.  The default assumption would then be that 
both parties are notified when conferencing occurs.  The subscription could 
be implicit.  This doesn't mean that someone won't withhold Notifies, but 
at least full disclosure is possible and recommended.  Note, this wouldn't 
preclude saying that a party has joined that wishes to remain 
anonymous.  This does not preclude the optimization of the number of 
subscriptions and notifies that Rohan had suggested.

If someone could explain the motivation for keeping party A in the dark 
about how many people he is talking to, I would like to hear it.

Mike

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From: Rohan Mahy <[email-masked]>
Date: Fri, 24 May 2002 08:30:00 -0700 (PDT)

> with other features such as 'consultative transfer' or even 'call pick

should work fine with attended transfer and call pickup, but a UA that
honors the request should either refuse the invitation with the privacy
request or not offer the consulative transfer or conference option to the
user (it could offer attended transfer instead for example).

hope this helps.
thanks,
-rohan