Subject: [SIP] More on privacy

From: "Drage, Keith (Keith)" <[email-masked]>
Date: Tue, 6 Feb 2001 13:14:56 -0000

To add a further issue to the current discussions on privacy.

The current specification of trusted versus untrusted really only deals with
the presentation of information to untrusted entities.

In the ISDN/PSTN world there is also the concept of information being
provided by an untrusted source, for example an separate enterprise network,
or a user attached to that separate enterprise network. 

In some cases the untrusted source may be the only entity able to provide
truly accurate information. Therefore for Calling Line Identification
Presentation there is a special indicator of user provided unscreened.

This means that in ISDN we have an either or situation for CLIP, the user is
either told:

-	this is the number for dialback purposes, but you cannot trust the
reliability of this information because I cannot check it.

or

-	this is the number for dialback purposes, but I have only provided
you with the information I can check, therefore it may not get you back to
the real source of the call, but only to the enterprise network that sourced
it.

In SIP we could have the possibility of providing both, but we would need to
discuss how we would identify these identifiers. For example two different
identifier tags in the Remote-Party_ID header, or a common identifier tag,
but a separate indication of level of screening.

Keith
Keith Drage
Lucent Technologies
Tel: +44 1793 776249
Email: [email-masked]

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---

From: Flemming Andreasen <[email-masked]>
Date: Tue, 06 Feb 2001 16:53:30 -0500

There is currently an "rpi-screen" parameter defined in the privacy draft which
basically tags the Remote-Party-ID as verified/screened or not. I'm not sure I
understand why it doesn't address what you want to achieve here.

-- Flemming

--
Flemming Andreasen
Cisco Systems