Subject: [MMUSIC] I-D Action: draft-ietf-mmusic-ice-sip-sdp-18.txt

From: [email-masked]
Date: Fri, 30 Mar 2018 14:08:06 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the Multiparty Multimedia Session Control WG of the IETF.

        Title           : Session Description Protocol (SDP) Offer/Answer procedures for Interactive Connectivity Establishment (ICE)
        Authors         : Marc Petit-Huguenin
                          Suhas Nandakumar
                          Ari Keranen
	Filename        : draft-ietf-mmusic-ice-sip-sdp-18.txt
	Pages           : 42
	Date            : 2018-03-30

Abstract:
   This document describes Session Description Protocol (SDP) Offer/
   Answer procedures for carrying out Interactive Connectivity
   Establishment (ICE) between the agents.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-mmusic-ice-sip-sdp/

There are also htmlized versions available at:
https://tools.ietf.org/html/draft-ietf-mmusic-ice-sip-sdp-18
https://datatracker.ietf.org/doc/html/draft-ietf-mmusic-ice-sip-sdp-18

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-mmusic-ice-sip-sdp-18

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/

---

From: Suhas Nandakumar <[email-masked]>
Date: Fri, 30 Mar 2018 14:09:10 -0700

Hello All

  We submitted version 18 that fixes the section numbering issues pointed
out by Christer

Thanks
Suhas

On Fri, Mar 30, 2018 at 2:08 PM, <[email-masked]> wrote:

>         Title           : Session Description Protocol (SDP) Offer/Answer
> procedures for Interactive Connectivity Establishment (ICE)
> _______________________________________________
> mmusic mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/mmusic
>

---

From: Flemming Andreasen <[email-masked]>
Date: Sat, 31 Mar 2018 14:27:48 -0400

Hi Suhas

Thanks for quickly updating and submitting the document, which I have 
reviewed. A couple of questions:

- Section 3.2.2: Why is it forbidden to include the "rtcp" attribute 
when the RTCP port number is one higher than the RTP port number ?

- Section 3.2.5, list item 3 says:
<quote>

    3.  If the default candidates were relayed candidates learned through
        a TURN server, the agent MUST create permissions in the TURN
        server for the IP addresses learned from its peer in the SDP it
        just received.  If this is not done, initial packets in the data
        stream from the peer may be lost.

</quote>
The text in and by itself seems reasonable, however I am not following 
how this relates to ICE mismatch and hence why it is part of this list 
(which in turn makes it difficult to understand). Let's say it's an 
offer SDP: The default candidates are relayed through a TURN server that 
the offerer uses, however you are now saying the answerer (agent) needs 
to create a permission in the TURN server?

- Section 3.3.4: What is considered the "lifetime of the ICE session" ? 
Does it end when we do an ICE restart ? Some clarification would be 
helpful.

- Section 10, IANA Considerations, SDP Attributes: Contact information 
has been changed to IESG and there is a new "URIs" section related to 
this in the References. I haven't heard about this new practice before - 
can you elaborate ?

- Section 10.1.8: Why not use a mux category of NORMAL instead of 
TRANSPORT for the session-level ice-pacing attribute (not that it 
matters much in practice since it's a session-level attribute) ?

I also have some editorial comments which I will send to you off-line.

Thanks

-- Flemming

On 3/30/18 5:09 PM, Suhas Nandakumar wrote:
> Hello All
>
>   We submitted version 18 that fixes the section numbering issues 
> pointed out by Christer
>
> Thanks
> Suhas
>
> On Fri, Mar 30, 2018 at 2:08 PM, <[email-masked] 
> <mailto:[email-masked]>> wrote:
>
>
>             Title           : Session Description Protocol (SDP)
>     Offer/Answer procedures for Interactive Connectivity Establishment
>     (ICE)
>     <https://datatracker.ietf.org/doc/draft-ietf-mmusic-ice-sip-sdp/>
>
>     <https://tools.ietf.org/html/draft-ietf-mmusic-ice-sip-sdp-18>
>     <https://datatracker.ietf.org/doc/html/draft-ietf-mmusic-ice-sip-sdp-18>
>
>     <https://www.ietf.org/rfcdiff?url2=draft-ietf-mmusic-ice-sip-sdp-18>
>
>
>     until the htmlized version and diff are available at
>     tools.ietf.org <http://tools.ietf.org>.
>
>     <ftp://ftp.ietf.org/internet-drafts/>
>
>     [email-masked] <mailto:[email-masked]>
>     <https://www.ietf.org/mailman/listinfo/mmusic>
>
>
>
>

---

From: Roman Shpount <[email-masked]>
Date: Sat, 31 Mar 2018 14:43:59 -0400

On Sat, Mar 31, 2018 at 2:27 PM, Flemming Andreasen <[email-masked]>
wrote:

> - Section 3.2.2: Why is it forbidden to include the "rtcp" attribute when
> the RTCP port number is one higher than the RTP port number ?
>

The rtcp attribute in this case is redundant since if rtcp attribute is
absent, RTCP will be sent to same IP as RTP and port number one higher then
the RTP.

Regards,
_____________
Roman Shpount

---

From: Flemming Andreasen <[email-masked]>
Date: Sat, 31 Mar 2018 15:38:12 -0400

Understood, however is there a need to actively forbid its use in that 
case ?

Thanks

-- Flemming

On 3/31/18 2:43 PM, Roman Shpount wrote:
> On Sat, Mar 31, 2018 at 2:27 PM, Flemming Andreasen 
> <[email-masked] <mailto:[email-masked]>> wrote:
>
>     - Section 3.2.2: Why is it forbidden to include the "rtcp"
>     attribute when the RTCP port number is one higher than the RTP
>     port number ?
>
>
> The rtcp attribute in this case is redundant since if rtcp attribute 
> is absent, RTCP will be sent to same IP as RTP and port number one 
> higher then the RTP.
>
> Regards,
> _____________
> Roman Shpount
>

---

From: Suhas Nandakumar <[email-masked]>
Date: Sat, 31 Mar 2018 22:12:07 +0000

Hi Flemming

Earlier version of the draft didn’t had that restriction. It was added at
later point due to wg discussion almost 2 years back. Roman and Thomas
Stach would know more details on the exact reasons

I am mobile right now and can try finding from archives for the reasoning

Thanks
Suhas