Re: [MMUSIC] The simulcast colon

Bo Burman <> Sat, 24 October 2015 17:20 UTC

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From: Bo Burman <>
To: "Mo Zanaty (mzanaty)" <>, Peter Thatcher <>
Thread-Topic: [MMUSIC] The simulcast colon
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Date: Sat, 24 Oct 2015 17:20:34 +0000
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Subject: Re: [MMUSIC] The simulcast colon
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I note that 4566bis ABNF for "attribute" says:

   ; sub-rules of 'a='
   attribute =           (att-field ":" att-value) / att-field
   att-field =           token
   att-value =           byte-string

The colon does not seem to be a "should" to me, but rather a requirement for any SDP attribute that is not a boolean.
Is there really any slack in how this can be implemented by SDP parsers?

To comply with 4566bis ABNF and still keep a single separator, you should rather remove the space.


From: mmusic [] On Behalf Of Mo Zanaty (mzanaty)
Sent: den 22 oktober 2015 15:48
To: Peter Thatcher
Subject: Re: [MMUSIC] The simulcast colon

The colon was added after others pointed out that attributes with further parameters should have a colon after the attribute. I don't know how many parsers actually care about that rule, but it seems safer to stick with the convention even if it bothers a few human eyes.


On Oct 22, 2015, at 12:54 AM, Peter Thatcher <<>> wrote:
+1 to removing the colon

On Wed, Oct 21, 2015 at 1:05 PM, Martin Thomson <<>> wrote:
Is annoying me.  Do we really need two separators (i.e., the colon and
the space)?

BTW,  the examples in the draft have c= and m= lines in the wrong
order, though I'm sure that I'm not the first to note this.

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