Subject: [Sip] SIP WG - 4 - Last Call Review Comments - draft-ietf-sip-call-auth -02.txt

From: "Mary Barnes" <[email-masked]>
Date: Wed, 19 Sep 2001 22:54:57 -0500

Hi Bill,

I'm doing a Last Call Review on draft-ieft-sip-call-auth-02.txt and have the
following comments:  

Pure NITS:
----------

1. General (1st example: Section 5.2.4, 1st paragraph) : Propose that the
phrase "termination Policy Decision Point"  be replaced with "terminating
Policy Decision Point". 

2. General:  Propose that the details of the message flows in section 6 have
numbers to correlate the message with the appropriate description.  (I had a
simpler proposal to do a general sweep to ensure that the paragraphs began
with something like:  "Upon receipt of the INVITE, the UAS ....".  However,
I also noticed that there isn't a text description for every message, see
point 5 below for details on at least one of these. I do recognize that some
of the processing is annotated in the flow itself, so overall I think the
technical content is there somewhere, so I have classified this as a NIT). 

Technical points/inconsistencies:
---------------------------------

1. Section 6.1.1 : The implicit assumption here is that the 180/3 will
always contain an SDP (as the Originating Proxy knows about the media
characteristics from 183). This assumption should be explicitly stated.
Propose that the following sentence be added to the end of the 1st
paragraph: "This model has an implicit assumption that the 180/3 always
contains an SDP,   thus the Originating Proxy knows the media
characteristics upon receipt of the 183 message." 

2. Section 6.1.1, para 8: the sentence should be rephrased to: "Upon receipt
of the 183 message, the UAC stores the Media-Authorization-Token."

3. Section 6.1.1. paragraph 9: a NIT, but consistent with rewording in point
3. Propose rewording the last part of this paragraph beginning with the
phrase: "... along with Authorization..." as " along with the previously
stored Media-Authorization-Token."

4. Section 6.1.2, paragraph 2: "Since the Destination SIP-proxy ....
initiates a Policy-Setup message to the termination Policy Decision Point
(PDPt)." - suggest that the phrase "on receipt of an INVITE" be added to the
end of the above sentence for clarity, to make this - "Since the Destination
SIP-proxy .... initiates a Policy-Setup message to the termination Policy
Decision Point (PDPt), on receipt of an INVITE."

5. Section 6.1.2, paragraph 3: For clarity, propose the following as the
last sentence:  "The Token is placed in the INVITE message and forwarded to
the UAS." 

6. Section 6.1.2, next to the last paragraph (10): RSVP-RESVo should be
RSVP-RESVt.

7. Section 6.1.2, last paragraph: Reword as:  "Upon receipt of the
RSVP-RESVCONFo, the UAS sends the 200 OK and awaits the ACK response from
the far end UAC."

8. Section 6.2.1 - Next to the last paragraph. The phrase RSA-REQ should be
replaced with DSA-REQ (more of a NIT, really).

9 Section 6.2.1 - Either remove the last sentence or add the 200 OK and Ack
to the flow and add a sentence indicating that "Upon receipt of the RSVP
RESVCONFo message, the UAC sends a 200 OK to the OP." 

10. Section 6.2.2 - Last paragraph. The RSA-REQ should be DSA-REQ.  

11. Section 6.2.2 - Last paragraph. Either delete the last sentence and
replace UAC with UAS or better yet, just remove the " which is acknowledged
by UAC via DSA-ACK message" clause from the next to the last sentence. 

12. Section 6.2.2. - Figure 4 - either remove the 200 OK,  or add an ACK and
the following 2 sentences to the end of 6.2.2.: 
"After sending the DSA-ACK, the UAS sends a 200 OK to the DP.  The 200 OK is
acknowledged by an ACK from the DP to the UAS."  

Regards,
Mary H. Barnes
IMS Solutions Standards Strategy
[email-masked]
972-684-5432
Wireless 817-703-4806