Re: [MMUSIC] Finding a max length of "a=mid" attribute

Paul Kyzivat <pkyzivat@alum.mit.edu> Wed, 03 March 2021 14:31 UTC

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To: mmusic@ietf.org
References: <e3aef40f-8f4e-5205-3ac1-b3e715c5e5ad@alvestrand.no>
From: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Date: Wed, 3 Mar 2021 09:31:51 -0500
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Archived-At: <https://mailarchive.ietf.org/arch/msg/mmusic/rKkfIxIvHzECuXSqy0p7-EEh4XE>
Subject: Re: [MMUSIC] Finding a max length of "a=mid" attribute
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On 3/3/21 3:51 AM, Harald Alvestrand wrote:
> I'm searching for the source of a max length limit on the "a=mid" 
> attribute.
> 
> I couldn't find it in RFC 5888 (grouping framework) or RFC 8843 (BUNDLE).
> 
> Does anyone remember where it's supposed to be?
> 
> (I have code that will insist that it should be 16 bytes or less, but 
> I'm trying to verify that this is the correct limit.)

Its defined as a token (from RFC4566/8866). And that is:

   token = 1*(token-char)

There is no upper limit on the length. You can't impose a limit for 
implementation convenience. But practically speaking it is limited by 
the length of the message body that contains it, so you could code using 
an offset+length into the message buffer.

	Thanks,
	Paul