Subject: [Stox] I-D Action: draft-ietf-stox-groupchat-06.txt

From: [email-masked]
Date: Thu, 09 Oct 2014 22:15:23 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.
 This draft is a work item of the SIP-TO-XMPP Working Group of the IETF.

        Title           : Interworking between the Session Initiation Protocol (SIP) and the Extensible Messaging and Presence Protocol (XMPP): Groupchat
        Authors         : Peter Saint-Andre
                          Saul Ibarra
                          Salvatore Loreto
	Filename        : draft-ietf-stox-groupchat-06.txt
	Pages           : 36
	Date            : 2014-10-09

Abstract:
   This document defines a bidirectional protocol mapping for the
   exchange of instant messages in the context of a multiparty chat
   session among users of the Session Initiation Protocol (SIP) and
   users of the Extensible Messaging and Presence Protocol (XMPP).
   Specifically, this document defines a mapping between the SIP-based
   Message Session Relay Protocol (MSRP) and the XMPP Multi-User Chat
   (MUC) extension.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-stox-groupchat/

There's also a htmlized version available at:
http://tools.ietf.org/html/draft-ietf-stox-groupchat-06

A diff from the previous version is available at:
http://www.ietf.org/rfcdiff?url2=draft-ietf-stox-groupchat-06

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

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From: Peter Saint-Andre - &yet <[email-masked]>
Date: Fri, 10 Oct 2014 06:55:39 -0600

This was my attempt to address Ben Campbell's feedback on architecture, 
which necessitated changes to all the protocol flows and examples, too.

Reviews would be appreciated. :-)

Thanks!

Peter

On 10/9/14, 11:15 PM, [email-masked] wrote:
> _______________________________________________
> stox mailing list
> [email-masked]
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>

-- 
Peter Saint-Andre
https://andyet.com/

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From: Saúl Ibarra Corretgé <[email-masked]>
Date: Wed, 15 Oct 2014 22:57:58 +0200

On 10 Oct 2014, at 14:55, Peter Saint-Andre - &yet <[email-masked]> wrote:

> This was my attempt to address Ben Campbell's feedback on architecture, which necessitated changes to all the protocol flows and examples, too.
> 

Thanks for getting back to this!

Some observations:

In example 3,c an we ditch ";automata;message;event=“conference””? The only thing that matters is “is focus” and the rest might just add confusion, specially the “event=‘conference’” part.

We have been using “SIP-to-XMPP” and “XMPP-to-SIP” all along, but now some sections make the distinction and a new "XMPP-to-MSRP” thing appears. Do we want to make this distinction all across or just in the architecture section? For the purpose of gatewaying, SIP and MSRP go together, even if technically they can be different entities. To be clear, the only thing that sounds a bit weird to me is “XMPP-to-MSRP”.

Section 5.8: typo: “focsu”.

Example 27: add “nickname private-messages” to a=chatroom

Example 28: I’d say “SIP-to-XMPP gateway acks session”

Other that these minor issues it LGTM!

Cheers,

--
Saúl Ibarra Corretgé
AG Projects

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From: Peter Saint-Andre - &yet <[email-masked]>
Date: Thu, 16 Oct 2014 19:44:44 -0600

On 10/15/14, 2:57 PM, Saúl Ibarra Corretgé wrote:

> We have been using “SIP-to-XMPP” and “XMPP-to-SIP” all along, but now
> some sections make the distinction and a new "XMPP-to-MSRP” thing
> appears. Do we want to make this distinction all across or just in
> the architecture section? For the purpose of gatewaying, SIP and MSRP
> go together, even if technically they can be different entities. To
> be clear, the only thing that sounds a bit weird to me is
> “XMPP-to-MSRP”.

Hi Saúl, thanks for the feedback!

Section 4 currently has the following paragraph:

    These are logical entities, and several of them might be co-located
    in the same physical entity; e.g., the SIP conference focus and MSRP
    switch and associated gateways, or the XMPP server and MUC service
    and associated gateways, might be part of the same deployed code.

I propose that we change it to:

    These are logical entities, and several of them might be co-located
    in the same physical entity.  For example, the SIP conference focus
    and MSRP switch and associated gateways, or the XMPP server and MUC
    service and associated gateways, might be part of the same deployed
    code.  In addition, it is likely that an XMPP service would not have
    separate gateways for XMPP-to-SIP translation and XMPP-to-MSRP
    translation, but would instead have a single gateway.

I agree with you that the concept of a dedicated gateway from XMPP to 
MSRP seems strange. In particular, I somewhat doubt that, in practice, 
an XMPP server would separately resolve the hostname of the MSRP switch 
(as described in Section 6.2 of RFC 4975) and send MSRP traffic over a 
separate connection; instead, in practice I think it would piggyback the 
MSRP traffic over its connection to the conference focus, which it would 
already be using for SIP traffic. However, for the sake of a clear 
description I think it is best to keep the logical entities and 
protocols separate from the physical implementation and deployment, as 
we have done in the latest version of the -groupchat document. The 
modified paragraph above covers the matter in enough depth that a smart 
implementer could figure it out.

Peter

-- 
Peter Saint-Andre
https://andyet.com/

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From: Saúl Ibarra Corretgé <[email-masked]>
Date: Mon, 20 Oct 2014 23:51:14 +0200

On 17 Oct 2014, at 03:44, Peter Saint-Andre - &yet <[email-masked]> wrote:

> I agree with you that the concept of a dedicated gateway from XMPP to MSRP seems strange. In particular, I somewhat doubt that, in practice, an XMPP server would separately resolve the hostname of the MSRP switch (as described in Section 6.2 of RFC 4975) and send MSRP traffic over a separate connection; instead, in practice I think it would piggyback the MSRP traffic over its connection to the conference focus, which it would already be using for SIP traffic. However, for the sake of a clear description I think it is best to keep the logical entities and protocols separate from the physical implementation and deployment, as we have done in the latest version of the -groupchat document. The modified paragraph above covers the matter in enough depth that a smart implementer could figure it out.
> 

Agreed! LGTM.

--
Saúl Ibarra Corretgé
AG Projects

---

From: Peter Saint-Andre - &yet <[email-masked]>
Date: Tue, 21 Oct 2014 10:45:10 -0600

>> I agree with you that the concept of a dedicated gateway from XMPP to MSRP seems strange. In particular, I somewhat doubt that, in practice, an XMPP server would separately resolve the hostname of…

Great. I'll submit a revised I-D sometime soon. :-)

Peter

-- 
Peter Saint-Andre
https://andyet.com/