Re: [rtcweb] [MMUSIC] Is bundle just a port override? (UNCLASSIFIED)

"Roy, Radhika R CIV USARMY (US)" <> Thu, 21 March 2013 12:15 UTC

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From: "Roy, Radhika R CIV USARMY (US)" <>
To: Harald Alvestrand <>, "Mo Zanaty (mzanaty)" <>
Thread-Topic: [rtcweb] [MMUSIC] Is bundle just a port override? (UNCLASSIFIED)
Date: Thu, 21 Mar 2013 12:15:10 +0000
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Subject: Re: [rtcweb] [MMUSIC] Is bundle just a port override? (UNCLASSIFIED)
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Classification: UNCLASSIFIED
Caveats: NONE

So, it is ugly vs. uglier vs. ugliest ...

-----Original Message-----
From: [] On Behalf Of
Harald Alvestrand
Sent: Thursday, March 21, 2013 8:10 AM
To: Mo Zanaty (mzanaty)
Subject: Re: [rtcweb] [MMUSIC] Is bundle just a port override?

On 03/21/2013 06:59 AM, Mo Zanaty (mzanaty) wrote:
> Hi Harald,
> You're right, both are essentially groupings, and all of our wheels have
ugly angles. To me, the ugly angles in bundle are unnecessary indirection by
grouping with artificial bindings (mid), and that it pretends to be more
than it is. To me, it is just a port override, but with unnecessary
indirection. Why not just say the port you want to use directly?
> m=audio 10000 RTP/AVP 0
> m=video 10002 RTP/AVP 31
> a=port 10000
> vs.
> a=group:BUNDLE foo bar
> m=audio 10000 RTP/AVP 0
> a=mid:foo
> m=video 10002 RTP/AVP 31
> a=mid:bar
> Why is the direct approach more complex? Why is ICE any different in
either approach?
You don't know the port you'll be using ahead of time with ICE; you have 
to put ICE into all the M-lines in order to be able to negotiate ICE 
when you don't get the bundling.

So in addition to specifying the port on the m= line, you have to uglify 
your solution by stating rules that say "if you accept this alternate 
port, you also have to accept these special rules for ICE", and all the 
other stuff that Christer uncovered and is documented in his draft.

And nothing that looks as the SDP without knowing the special semantics 
of bundle can know that the fact that a=port in those 2 M-lines implies 
special treatment of ICE.

It's a grouping framework. I don't want to create new grouping 
frameworks; the one we have is bad enough.

I think your angles will produce a bumpier ride than mine :-)

> Cheers,
> Mo

Classification: UNCLASSIFIED
Caveats: NONE