Subject: Re: [MMUSIC] Data channel dcsa attribute usage and IANA - the pull request

From: Christer Holmberg <[email-masked]>
Date: Thu, 29 Aug 2019 12:47:35 +0000

Hi,

I have created a pull request that:

  1.  Describes including the SDP media direction attributes in dcsa attributes
  2.  Adds the IANA registry updates for the SDP attributes that can be included in dcsa attributes
  3.  Minor nit fixes, found by Gunnar and myself

https://github.com/cdh4u/draft-datachannel-t140/pull/6

Regards,

Christer

From: "Roni Even (A)" <[email-masked]>
Date: Thursday, 29 August 2019 at 12.50
To: Christer Holmberg <[email-masked]>, "[email-masked]" <[email-masked]>, "[email-masked]" <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Subject: RE: [MMUSIC] Data channel dcsa attribute usage and IANA

Hi,
I think that dcsa(subprotocol) would have been enough, at least based on channel-sdpneg document, maybe Paul can help

Roni

From: Christer Holmberg [mailto:[email-masked]]
Sent: Thursday, August 29, 2019 12:25 PM
To: Roni Even (A); [email-masked]; [email-masked]
Cc: [email-masked]
Subject: Re: [MMUSIC] Data channel dcsa attribute usage and IANA

Hi,

One question for clarification:

Section 8.2.4.1 of RFC4566bis says:

      “Usage Level: Usage level(s) of the attribute.  This MUST be one or
      more of the following: session, media, source, dcsa and
      dcsa(subprotocol).”

…and in the Table in Section 8.2.4 it says:

“dcsa,dcsa(msrp)”

Q1: Why does it need to say both ‘dcsa’ and ‘dcsa(subprotocol)’? Isn’t it enough with ‘dcsa(subprotocol)’?

Regards,

Christer

From: mmusic <[email-masked]<mailto:[email-masked]>> on behalf of Christer Holmberg <[email-masked]<mailto:[email-masked]>>
Date: Thursday, 29 August 2019 at 11.27
To: "Roni Even (A)" <[email-masked]<mailto:[email-masked]>>, "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Cc: "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Subject: Re: [MMUSIC] Data channel dcsa attribute usage and IANA

Hi,

Thanks for the information! The last paragraph clarifies it.

So, draft-t140-usage-data-channel will update the IANA registry for the SDP attributes used inside the SDP dcsa attribute.

Regards,

Christer

From: "Roni Even (A)" <[email-masked]<mailto:[email-masked]>>
Date: Thursday, 29 August 2019 at 11.08
To: Christer Holmberg <[email-masked]<mailto:[email-masked]>>, "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Cc: "[email-masked]<mailto:[email-masked]>" <[email-masked]<mailto:[email-masked]>>
Subject: RE: Data channel dcsa attribute usage and IANA

Hi Christer,
To add to Paul’s response
Look at the last 2 paragraphs of section 5.2.1   https://tools.ietf.org/html/draft-ietf-mmusic-data-channel-sdpneg-28#section-5.2.1

Roni

From: mmusic [mailto:[email-masked]] On Behalf Of Christer Holmberg
Sent: Wednesday, August 28, 2019 1:33 PM
To: [email-masked]<mailto:[email-masked]>
Cc: [email-masked]<mailto:[email-masked]>
Subject: [MMUSIC] Data channel dcsa attribute usage and IANA

Hi,

Section 7.2 of draft-ietf-mmusic-msrp-usage-data-channel updates the IANA registry for the SDP ‘setup’ attribute, by indicating that it can be used inside an SDP ‘dcsa’ attribute.

Do we really need to update the IANA registry for all SDP attributes that can be included in an ‘dcsa’ attribute???

There is no text in draft-mmusic-data-channel-neg about having to modify the IANA registry for such attributes.

Regards,

Christer