[sipcore] Questions on location conveyance and dereferencing

"Elwell, John" <john.elwell@siemens-enterprise.com> Thu, 12 August 2010 08:20 UTC

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From: "Elwell, John" <john.elwell@siemens-enterprise.com>
To: "sipcore@ietf.org" <sipcore@ietf.org>
Date: Thu, 12 Aug 2010 10:21:19 +0200
Thread-Topic: Questions on location conveyance and dereferencing
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Subject: [sipcore] Questions on location conveyance and dereferencing
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1. Draft-ietf-sipcore-location-conveyance-03 defines PRES, SIP and SIPS URI schemes for LbyR. For SIP and SIPS, there seems to be an absence of specification of what event package to use when submitting a SIP or SIPS SUBSCRIBE request for dereference purposes. If it is not defined in this specification, where is it defined?

2. Concerning PRES-URIs, we have the following text in 4.6:
"If a location URI is included in a SIP request, it MUST be a SIP-, 
   SIPS- or PRES-URI.  When PRES: is used, as defined in [RFC3856], if 
   the resulting resolution resolves to a SIP: or SIPS: URI, this 
   section applies."

The words "this section applies" are rather strange, because there is little else in this section. Maybe in a previous iteration there was more information here (on how to use a SIP/SIPS URI for dereference purposes). As things stand, the absence of information on how to resolve a SIP- or SIPS-URI applies also to PRES-URIs.

3. Also there is nothing to say what to do if the PRES URI fails to resolve to a SIP or SIPS URI.

4. The "MUST be a SIP-, SIPS- or PRES-URI" text in cited above seems to preclude the addition of future URI schemes, which seems to be in conflict with 8.6 (registry establishment for location URIs).