Subject: [MMUSIC] Bundle, TURN and Legacy Interop

From: "Hutton, Andrew" <[email-masked]>
Date: Wed, 13 Mar 2013 20:00:15 +0000

Hi,

It seems that one of the motivations of the current bundle-03 proposal is that the first offer is compatible with a legacy device and that a second offer is required for bundle (See http://www.ietf.org/proceedings/86/slides/slides-86-mmusic-9.pdf).

One issue that I see is that if TURN is being used there could be a significant overhead in creating the first offer is multiple TURN allocations are needed for each m-line which will all then have to be released if bundle is used.

I am not sure if there is a way to avoid this other but the draft should I think mention this issue.

Regards
Andy

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From: Christer Holmberg <[email-masked]>
Date: Wed, 13 Mar 2013 20:11:40 +0000

Hi,

Nothing prevents you from only sending host candidates in the first offer, of you want to do.

Regards,

Christer

Sent from Windows using TouchDown (www.nitrodesk.com)

-----Original Message-----
From: Hutton, Andrew [[email-masked]]
To: [email-masked] [[email-masked]]
Subject: [MMUSIC] Bundle, TURN and Legacy Interop
Hi,

Regards
Andy
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https://www.ietf.org/mailman/listinfo/mmusic

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From: "Hutton, Andrew" <[email-masked]>
Date: Wed, 13 Mar 2013 21:00:40 +0000

There is if you have been configured to use TURN and are known to need to use it.

Andy

On 13 Mar 2013, at 16:11, "Christer Holmberg" <[email-masked]<mailto:[email-masked]>> wrote:

Hi,

Regards,

Christer

Sent from Windows using TouchDown (www.nitrodesk.com<http://www.nitrodesk.com>)

-----Original Message-----
From: Hutton, Andrew [[email-masked]<mailto:[email-masked]>]
To: [email-masked]<mailto:[email-masked]> [[email-masked]<mailto:[email-masked]>]
Subject: [MMUSIC] Bundle, TURN and Legacy Interop
Hi,

Regards
Andy
_______________________________________________
mmusic mailing list
[email-masked]<mailto:[email-masked]>
https://www.ietf.org/mailman/listinfo/mmusic

---

From: [email-masked] (Dale R. Worley)
Date: Thu, 14 Mar 2013 15:29:55 -0400 (EDT)

> From: "Hutton, Andrew" <[email-masked]>
> 
> It seems that one of the motivations of the current bundle-03
> proposal is that the first offer is compatible with a legacy device
> and that a second offer is required for bundle (See
> http://www.ietf.org/proceedings/86/slides/slides-86-mmusic-9.pdf).

It seems to me that this is suboptimal from the point of view of
connection establishment.  It's not difficult to arrange an offer that
is compatible with both a legacy endpoint (except for perhaps TURN ICE
candidates for the fallback "constituent" ports) and with a supporting
endpoint.  The essential thing is to have a separate bundle m= line so
you can in effect offer both the bundle and the constituents
simultaneously.

If the offerer discovers that it is talking to a legacy endpoint, it
can update the offer with TURN ICE candidates for the constituent
ports.  (If the offerer doesn't want to have to reoffer for legacy
endpoints, it can preallocate enough TURN candidates.)

The result is that you can establish communication with supporting
endpoints in one offer/answer cycle, and the offerer chooses between
needing a reoffer for legacy endpoints when TURN is required
vs. preallocating enough TURN relays.

I don't see a reason to optimize the offer/answer technique to slow
down connection to supporting endpoints and speed it up for legacy
endpoints.

Dale