Re: [rtcweb] Replacing a=extmap mapping in re-offer, is it legal?

Iñaki Baz Castillo <ibc@aliax.net> Mon, 07 August 2017 19:12 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Mon, 07 Aug 2017 21:12:12 +0200
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To: Taylor Brandstetter <deadbeef@google.com>
Cc: Christer Holmberg <christer.holmberg@ericsson.com>, "rtcweb@ietf.org" <rtcweb@ietf.org>
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Subject: Re: [rtcweb] Replacing a=extmap mapping in re-offer, is it legal?
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Good catch.

On Mon, Aug 7, 2017 at 8:21 PM, Taylor Brandstetter <deadbeef@google.com> wrote:
> Christer and I are in agreement. He's just saying "there should be a MUST
> NOT in the spec."
>
> And there is:
>
>> Identifiers values in the valid range MUST NOT be altered (remapped).
>
>
>
> On Mon, Aug 7, 2017 at 11:06 AM, Christer Holmberg
> <christer.holmberg@ericsson.com> wrote:
>>
>> Hi,
>>
>> >> Taylor's explanation makes sense. But, in this case:
>> >>
>> >> 1) Re-using the same value with a new mapping should be an explicit
>> >> MUST NOT
>> >>
>> >> 2) The re-offer should be rejected
>> >
>> > Hi Christer, I'm lost. If Taylor's explanation is ok, why 1) and 2)?
>>
>> Maybe I was unclear :)
>>
>> Taylor described why re-using a value for a new mapping doesn't work. I
>> think that should be explicitly described, and the text should say MUST NOT
>> re-use value for new mapping (hence 1).
>>
>> Second, IF an offerer still tries to re-use a value for a new mapping, the
>> text should say that the receiver MUST discard the offer (hence 2).
>>
>> Regards,
>>
>> Christer
>
>



-- 
Iñaki Baz Castillo
<ibc@aliax.net>