[AVT] Action items from IETF 52 meeting

[Stephen Casner <[e-mail]>]

This is a list of the action items from the two AVT sessions at
IETF52.  We took "hums" on these items in the meeting, but as has been
stated before, working group decisions are officially made on the
mailing list and not in the meetings.  (Also, I must say that the hums
were not very strong on Monday night, in part due to a smaller than
usual number of participatnts in a rather large room).  Therefore, we
solicit confirmations or objections on these actions -- we want to
hear both "yeas" and "nays".

The working group agreed that the following drafts should go to
working group last call for comments (pending agreement on the list).
Since there are several drafts at once, and since the holidays come up
soon, we propose that the last call period will end January 11.  All
of these are to go to Proposed Standard (except as noted):

    Comfort Noise payload format (draft-ietf-avt-rtp-cn-04.txt)
	The main question: will there be any backwards compatibility
	problems with early implementations of CN that included only
	the amplitude and not spectral information?

    Enhanced CRTP (draft-ietf-avt-crtp-enhance-03.txt)
    Tunneled CRTP (draft-ietf-avt-tcrtp-05.txt)
	These drafts comprise AVT's product for RTP multiplexing.

    Unequal Erasure Protection (draft-ietf-avt-uxp-01.txt)
    Uneven Level Protection (draft-ietf-avt-ulp-02.txt )
	These two drafts provide somewhat similar services for
	providing different levels of error protection for different
	parts of a packet stream, but for different environments or
	requirements.  In order to convince the IESG that we should
	standardize two such methods, each draft needs to have an
	applicability statement to indicate when it should be used.
	The uxp draft already has this; the ulp draft needs to add it.
	From these statements we will compose the cover letter to the
	IESG for these two drafts.

    MPEG-4 generic (draft-ietf-avt-mpeg4-multisl-03.txt)
    MPEG-4 simple (draft-ietf-avt-mpeg4-simple-00.txt)
	These drafts go together because the second is a "profile" of
	the first.  Colin Perkins has identified some additional
	changes needed to improve clarity in the generic draft, but
	these will be taken as wg last call comments along with the
	comments that other wg members may have.

    Distributed Speech Recognition (draft-ietf-avt-dsr-00.txt)

    Extended RTP Profile for RTCP-based Feedback
	An open issue was resolved for the profile specification
	(draft-ietf-avt-rtcp-feedback-01.txt) at this meeting.  When
	the draft is updated, it will be ready for wg last call.  A
	companion draft reporting on simulation studies of the timing
	algorithm (draft-burmeister-avt-rtcp-feedback-sim-00.txt) goes
	to wg last call for publication as Informational.

    Secure RTP profile (draft-ietf-avt-srtp-02.txt)
	This draft includes the description of an open issue.  A
	resolution was agreed among the authors before the meeting and
	confirmed at the meeting.  When the draft is updated, it will
	be ready for wg last call.

The working group agreed that the following drafts should be accepted
as working group tasks (pending agreement on the list):

    RTP Payload Format for EVRC, SMV and Frame-Based Vocoders
    (draft-li-avt-vocoder-00.txt)
	This draft is the generalization of the EVRC payload format
	draft on which we already did a wg last call.  However, the
	authors decided to merge with proposals for the SMV payload
	format.  At this meeting, we agreed to accept this as a wg
	item and also to issue wg last call on it after some rewording
	to make clear that this payload format may be used for future
	frame-based vocoders but that doing so is NOT preferred over
	development of an encoding-specific payload format.

    RTP Payload Format for AC-3 Streams
    (draft-flaks-avt-rtp-ac3-00.txt)

    MWPP: A resilient MIDI RTP packetization
    (draft-lazzaro-avt-mwpp-midi-nmp-00.txt)

    RTP payload format for JPEG 2000 video streams
    (draft-edwards-avt-rtp-jpeg2000-00.txt)

    RTCP Extension for SSM Sessions with Unicast feedback
    (draft-chesterfield-avt-rtcpssm-02.txt)
	The wg co-chairs were under the mistaken impression that this
	proposal had already been accepted as a wg task at a previous
	meeting, but apparently not.  So we did not hum on this one at
	this meeting, but we are asking for confirmation or objection
	on the list.

At this meeting we had a presentation of a "meta payload format" (in
the same sense as the FEC payload format) for RTP retransmission
(draft-leon-rtp-retransmission-01.txt) to be used with the extended
RTP profile for RTCP-based feedback.  This is a new proposal that uses
separate RTP sessions for the primary and retransmission traffic.  At
previous meetings, draft-ietf-avt-rtp-selret-03.txt was presented to
describe an alternative payload format that keeps all of the packets
in one RTP session but must therefore carry more information in the
payload header and must modify some of the semantics of RTP fields.
There was recently some discussion on the mailing list among the
authors of these two drafts regarding the tradeoffs.  We co-chairs are
asking for wider discussion of these tradeoffs with the goal to have
the working group agree on which of these should be published as a
Proposed Standard.

We also had a presentation at this meeting of a new payload format
proposal (draft-barany-avt-efr-00.txt) for GSM-EFR speech.  There
already is a payload format for GSM-EFR specified by ETSI and
referenced in the RTP A/V profile.  This new proposal adds one or more
bits to carry quality information that would be inserted by gateways
between a non-RTP radio link and a packet net.  Because we want to
avoid having two payload formats for the same encoding unless there is
a strong justification, the author was requested to supply supporting
evidence for claim of improved MOS scores relative to just dropping
damaged frames.

In addition to these current action items, we have an update on a
previous action item, the RTP payload format and file storage format
for AMR and AMR-WB audio (draft-ietf-avt-rtp-amr-10.txt) that has
been waiting for IESG feedback.  The (rather delayed) IESG response
was that the draft was not written clearly enough.  Qiaobing Xie
stepped up quickly with an offer to rewrite the draft and has done the
first phase of that work.  Because we want to progress this draft as
quickly as possible since the delay has already been quite long, we
agreed to the following schedule:

  - The edited draft (or a URL) will be sent directly to the avt
    mailing list to avoid the Internet Draft administrator delay.  The
    target for this is next Monday or Tuesday.

  - We ask the wg to review the revised draft and provide comments by
    early next Friday.

  - On Friday, the draft will be revised to address any comments, then
    submitted to the I-D administrator.  The AVT co-chairs will send a
    request to the IESG asking to resume the review.

Thanks for your attention and your diligence in reading through the
drafts listed above in your spare time during the holidays!  (Hint,
hint.)
						-- Steve and Colin


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