[Sip] RE: [RAI] RAI review of draft-ietf-sip-hitchhikers-guide-03

[Avshalom Houri <AVSHALOM at il.ibm.com>]

Keith,

Thanks for the clarification.

Maybe this clarification should be part
of the document itself?

BR
--Avshalom

"DRAGE, Keith \(Keith\)" <drage at alcatel-lucent.com>

30/10/2007 10:01

To	Avshalom Houri/Haifa/IBM at IBMIL, <rai at ietf.org>, <sip at ietf.org>, <jdrosen at cisco.com>
cc
Subject	RE: [RAI] RAI review of draft-ietf-sip-hitchhikers-guide-03

(As WG chair)
 
Just a note that I should have
included with the WGLC.
 
The intention with this document
is to republish on a recurring basis, and therefore to keep it up to date
(say once a year or so).
 
The 1st versions is intended to
include gruu, outbound and ice, but apart from that, anything that is not
published in that timeframe will probably be removed unless there is exceptional
justification for keeping it, with the idea that it will appear in the
next version.
 
regards
 
Keith

---

From: Avshalom Houri [mailto:AVSHALOM at il.ibm.com]
Sent: Monday, October 29, 2007 10:40 AM
To: rai at ietf.org; sip at ietf.org; jdrosen at cisco.com
Subject: [RAI] RAI review of draft-ietf-sip-hitchhikers-guide-03


I have been assigned to review of draft-ietf-sip-hitchhikers-guide-03
from the perspective of presence and the SIMPLE group but ended up in
commenting on the whole document at the end. 

For background on RAI-ART, please see the FAQ at 
http://www.softarmor.com/rai/art/rai-art-FAQ.html

Please resolve these comments along with any other Last Call comments
you may receive. 

In my opinion this draft is basically ready for publication, but has
nits that should be fixed before publication. 

Citations from the draft are marked by <<< text from draft >>>

General comments 
---------------- 

By its nature there are a lot of reference to drafts in the document.
It will take a lot of time for these documents to become and RFC.
So how we are going to publish this as an RFC? Since when the
referenced drafts will become an RFC, this draft would have to be
updated with new drafts, will it be held in the 
RFC ED queue for ever? 

How do we gauge the usage of an RFC or a draft? There are many places
here that it is said that this or that RFC/draft got widely implemented
or not. 
How it is measured? The wide implementation test is used to decide
whether an RFC or draft are core or not and therefore there should be
some text explaining how the wide implementation was determined.

Better change RFC XXXX (before the reference number in []) to the name
of the draft (with no version number), it will make the ride smoother.

An introduction that details the various grouping should be added. It
should include additional text on the group and what was the criteria
for putting an RFC/draft in the group. 

2.  Scope of this Document 
-------------------------- 

<<< 
   o  Any specification that defines an extension to SIP itself,
where 
      an extension is a mechanism that changes or updates
in some way a 
      behavior specified in RFC 3261
>>> 

"to SIP itself" sounds vague. It will be better to say:"to
RFC 3261" 
instead. 
Maybe there should be an earlier definition of RFC 3261 as the SIP nucleus
(or the president of the galaxy) and that RFCs/drafts mentioned in this
document are based on their relation to it. 

<<< 
   Excluded from this list are requirements, architectures, registry
   definitions, non-normative frameworks, and processes.  Best
Current 
   Practices are included when they normatively define mechanisms
for 
   accomplishing a task. 
>>> 
    
"normatively define" not sure what is meant by normative with
respect to BCP. Seems like a contradiction in terms.

3.  Core SIP Specifications 
--------------------------- 

If we think on presence as eventually replacing registration, since it
carries much more information about the availability of the user, 
should we consider also presence as a towel? 

<<< 
   RFC 3261, The Session Initiation Protocol (S):  RFC 3261 [1]
is the 
      core SIP protocol itself.  RFC 3261 is an update
to RFC 2543 [9]. 
      It is the president of the galaxy [42] as far as the
suite of SIP 
      specifications is concerned. 
>>> 

RFC 3261 is a very big document. Should it be treated as one or it can
be divided into parts in this document e.g. proxy, client etc.? I am not
sure what would be better. 

4.  Public Switched Telephone Network (PSTN) Interworking
---------------------------------------------------------

Regarding RFC 3578 
Ugly in one corner of the galaxy may be beautiful on the other of it :-)

7.  Minor Extensions 
-------------------- 

<<< 
   RFC XXXX, Referring to Multiple Resources in SIP (S):  RFC
XXXX [44] 
      allows a UA sending a REFER to ask the recipient of
the REFER to 
      generate multiple SIP requests, not just one.  This
is useful for 
      conferencing, where a client would like to ask a conference
server 
      to eject multiple users. 
>>> 

Should not this be referred to in the conferencing section also?

<<< 
   RFC 4483, A Mechanism for Content Indirection in Session Initiation
   Protocol (SIP) Messages (S):  RFC 4483 [89] defines a mechanism
for 
      content indirection.  Instead of carrying an
object within a SIP 
      body, a URL reference is carried instead, and the
recipient 
      dereferences the URL to obtain the object.  The
specification has 
      potential applicability for sending large instant
messages, but 
      has yet to find much actual use.
>>> 

The specification has also potential for sending large presence
documents via a URL. 

<<< 
   RFC 4583, Session Description Protocol (SDP) Format for Binary
Floor 
   Control Protocol (BFCP) Streams (S):  RFC 4583 [91] defines
a 
      mechanism in SDP to signal floor control streams that
use BFCP. 
      It is used for Push-To-Talk and conference floor control.
>>> 

Should not this be referred to in the conferencing section also?

<<< 
   RFC XXXX, Connectivity Preconditions for Session Description Protocol
   Media Streams (S):  RFC XXXX [93] defines a usage of the precondition
      framework [59].  The connectivity precondition
makes sure that the 
      session doesn't get established until actual packet
connectivity 
      is checked. 
>>> 

Should not this be referred to in the QoS section also?

8.  Conferencing 
---------------- 

The Conferencing section should be before or after "Instant Messaging,
Presence and Multimedia" as it is also an application. See the comment
on whether presence is an application or not later.

10.  Event Framework and Packages 
---------------------------------- 

Suggest to divide this section to event framework section and to
packages section. The event framework should include 3265, 3903, 4662
and subnot-etags which define the event framework itself.
The other section will the packages sections that will list the
packages. 

Alternatively, many of the packages are mentioned in their proper
section so it may be that all the event packages can be fit into
their relevant section and there is not a need for packages section.

11.  Quality of Service 
----------------------- 

<<< 
   RFC 3313, Private SIP Extensions for Media Authorization (I):  RFC
      3313 [61] defines a P-header that provides a mechanism
for passing 
      an authorization token between SIP and a network QoS
reservation 
      protocol like RSVP.  Its purpose is to make sure
network QoS is 
      only granted if a client has made a SIP call through
the same 
      providers network.  This specification is sometimes
referred to as 
      the SIP walled garden specification by the truly paranoid
androids 
      in the SIP community.  This is because it requires
coupling of 
      signaling and the underlying IP network.
>>>       

Understand that being a "truly paranoid" is a virtue? :-)

15.  Security Mechanisms 
------------------------ 

Should not RFC 3323 (Privacy), RFC 3325 (Asserted-ID) and RFC 4474
(Identity) be mentioned here also?     

16.  Instant Messaging, Presence and Multimedia
----------------------------------------------- 

Maybe create an applications section and put also conferencing as a type
of an application. 

Including presence here with IM and multimedia seems that presence is
regarded as an additional type of media. I am not sure that I agree with
this. Presence is an enabler for many other applications and it deserves
a section of its own. 

It is very tempting to include the simple-simple content here
(as an appendix?). If simple-simple is not to be included here, there
should be at least a reference to simple-simple as for presence
there are so many documents that are essential for doing presence and
are not mentioned here (e.g. watcher format, RPID, presence rules,
partial notify and publish and many many more). Roughly counting, there
are about 20-25 RFCs/drafts that are very relevant to presence that are
mentioned in simple-simple in addition to the ones that are mentioned here.

The MSRP drafts seem to be forgotten? 

Thanks 
--Avshalom_______________________________________________
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