Re: [rtcweb] Working Group Last Call for draft-uberti-rtcweb-rfc8829bis-01.txt

[Justin Uberti <[e-mail]>]

On Sun, Oct 31, 2021 at 11:02 PM Roman Shpount <[e-mail]> wrote:

> On Mon, Nov 1, 2021 at 1:41 AM Justin Uberti <
> [e-mail]> wrote:
>
>>
>>
>>>
>>> >1. Make subsequent offers valid initial offers. This means adding some
>>> language explaining how the endpoint processing initial offer can detect
>>> that m= lines cannot be unbundled. Even if we add this language it will
>>> have backwards compatibility issues with anything that has not implemented
>>> it.
>>>
>>>
>>>
>>> I don’t agree with that suggestion. Because, in that case we could have
>>> done it from the beginning, as a general rule, without using port zero. But
>>> there were reason we chose not to allow shared addresses (with non-zero
>>> port values) in initial offers.
>>>
>>
>> We did come up with a=bundle-only mechanism to ensure backwards
>> compatibility, and none of us want to revisit that decision. However, I do
>> think that it would be consistent with Postel's Principle for the answerer
>> to properly handle the case where a 3PCC offer ends up with a shared
>> address, rather than failing simply because the offer does not appear to be
>> an initial offer.
>>
>>>
>>>
> In case of trickle ICE, would shared address be detected by the absence of
> ICE ufrag and pwd in the bundled m= line definition?
>

yes, exactly.