Re: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value

"Ali C. Begen (abegen)" <abegen@cisco.com> Tue, 05 August 2014 14:41 UTC

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From: "Ali C. Begen (abegen)" <abegen@cisco.com>
To: Brett Tate <brett@broadsoft.com>
Thread-Topic: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value
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Date: Tue, 5 Aug 2014 14:41:48 +0000
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Subject: Re: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value
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On Aug 5, 2014, at 5:12 PM, Brett Tate <brett@broadsoft.com> wrote:

> Hi,
> 
> Draft-ietf-mmusic-rfc4566bis-10 section 5.13 discusses two formats of
> attribute fields.  However, it doesn't appear to clearly indicate the
> validity/invalidity of colon without a value.

It says there are two forms. since "a=<attribute>:" is not listed as a form, I guess it simply means it is not valid usage.

> 
> Is an attribute such as "a=rtcp-xr:" valid?  

Not based on my knowledge.

> For instance, RFC 3611
> indicates that it is valid; however errata 3795 indicates that it
> potentially shouldn't be valid.

I am not sure why that errate is not verified. To me, 3611 has an abnf syntax error that should be fixed.

> 
> Should draft-ietf-mmusic-rfc4566bis-10 section 5.13 be updated to clarify
> the topic?

We can add a sentence to ban such a usage but now I wonder whether they have been attributes defined in that form in the past. Is anyone aware of any?

-acbegen

> 
> Thanks,
> Brett
> 
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