Re: [MMUSIC] WGLC on draft-ietf-mmusic-msrp-usage-data-channel-16

[Christer Holmberg <[e-mail]>]

Hi Paul,


>>>>>1. Should the draft say that it updates RFC 4975?
>>>>>The msrps scheme is also IANA-registered in RFC 4975 section 15.5.2.
>>>>>Please check if that registration need update because of the reuse
>> of the msrps scheme.
>>>>
>>>>Thanks for bringing this back. WG was asked for feedback about
>>> updating IANA registry or
>>>>keeping as it is, with the argument that data channel uses DTLS so it
>>>> would conform
>>>>original “msrps” requirement, that refers to TLS. There was no clear
>>>> outcome.
>>>>
>>>>If there are no comments opposing this, I would follow your comment
>>>> and add it to IANA updates section
>>
>>>Good.
>>
>>>Would it also be suitable to say that the draft updates RFC 4975,
>>> because of this?
>>
>>
>> I agree that a reference to the document should be added to the IANA
>> registry for the "msrps" scheme.
>>
>>
>> And, if people think 4975 should be updated, I guess we could say
>> something like:
>>
>>
>> "This document RFC 4975, by allowing the usage of the "msrps" scheme
>> when the underlying connection is protected with DTLS."
>
> The key is ensuring that the required usage is clear and unambiguous.
> Specifically, ISTM that a "msrps" URI together with a "dc" parameter
> implies that connecting to this requires use of a data channel over a
> DTLS association established using the address in the URI.
>
>> Following up on that, a question about the example in 4.8:
>>
>> The path attribute includes:
>>
>>    msrps://bob.example.com:54111/si438dsaodes;dc
>
> but the corresponding c= is:
>
>    c=IN IP4 198.51.100.79
>
> Am I to infer that =IN IP4 198.51.100.79 is the resolution of
> bob.example.com:54111? If so, why doesn't the c= reference
> bob.example.com:54111?

I think we should remove the port number for the path attribute.

As you know, we have tried to make it clear that the msrp URI is not used for routing, and that the path can be set to anything.

Do you want the address and port of the path URI to match the c= line?

Regards,

Christer