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Re: [MMUSIC] RFC 5245: ice-ufrags of length 256 vs stun maximum username length of 512 bytes

Martin Thomson <martin.thomson@gmail.com> Wed, 14 August 2013 16:10 UTC

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Date: Wed, 14 Aug 2013 17:10:48 +0100
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From: Martin Thomson <martin.thomson@gmail.com>
To: Philipp Hancke <fippo@goodadvice.pages.de>
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Subject: Re: [MMUSIC] RFC 5245: ice-ufrags of length 256 vs stun maximum username length of 512 bytes
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On 14 August 2013 07:54, Philipp Hancke <fippo@goodadvice.pages.de> wrote:
>
> Off by one?

Maybe.  It certainly looks like an off-by-one error in the specs,
though you could technically argue that both sets of length
restrictions apply, since they are independent.  After all, not all
users of the STUN username attribute are also doing ICE.

> For ice-pwd this isn't a problem, right?

This doesn't transit the network in STUN packets.  In SDP, the maximum
size is 256 characters, but that's not a limit that other signaling
protocols need to respect.

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