[AVTCORE] Comments on draft-he-avtcore-rtcp-green-metadata

Jonathan Lennox <jonathan.lennox@8x8.com> Thu, 21 July 2022 21:39 UTC

Return-Path: <jonathan.lennox@8x8.com>
X-Original-To: avt@ietfa.amsl.com
Delivered-To: avt@ietfa.amsl.com
Received: from localhost (localhost []) by ietfa.amsl.com (Postfix) with ESMTP id E2930C15A735 for <avt@ietfa.amsl.com>; Thu, 21 Jul 2022 14:39:30 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.108
X-Spam-Status: No, score=-2.108 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=8x8.com
Received: from mail.ietf.org ([]) by localhost (ietfa.amsl.com []) (amavisd-new, port 10024) with ESMTP id MfPb_0RyTapX for <avt@ietfa.amsl.com>; Thu, 21 Jul 2022 14:39:26 -0700 (PDT)
Received: from mail-qv1-xf29.google.com (mail-qv1-xf29.google.com [IPv6:2607:f8b0:4864:20::f29]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 922BAC15A73A for <avtcore@ietf.org>; Thu, 21 Jul 2022 14:39:23 -0700 (PDT)
Received: by mail-qv1-xf29.google.com with SMTP id m10so2249183qvu.4 for <avtcore@ietf.org>; Thu, 21 Jul 2022 14:39:23 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=8x8.com; s=googlemail; h=from:mime-version:subject:message-id:date:cc:to; bh=UZDhBP/gI85JEtDseu2FE7ydBWgov7OYqwygVxrkk0E=; b=YTOZRzSgXgBwAK2ZAgucQP+PYrobEQA1zYsPAegXuysfO7s4hDVl1sHG6I+if9LU4d Ow8ye26qF9M3FI5XkzG+pj03uEazEJC/5eCRv/g6IIstepvL9KlzJmFbDvy5fAYlYskA qp+cNt2q8hhVsVgj6sAjkL+EBsuPV6RILLsds=
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:mime-version:subject:message-id:date:cc:to; bh=UZDhBP/gI85JEtDseu2FE7ydBWgov7OYqwygVxrkk0E=; b=h+8bN4eYwdiaN2zImeBpnD+H+4041n9HbmIPhTFFl88A7G2IvWJnbGGA4Zo2dLyYfp +QM+Fo3siPurbkr6ShMxyzPY4C8oRfZHAQfEMmUwNml6yNv/T6jEejWGREaajWRZ8U4h bPO4dMiirlpzCr59WVaPS4R4AQcX3WwFOepjvt/z/FKNTKvMlpQGrKELPNvQJaN2Q2iJ 5R7Re2kr9TYqUYKYh/GMGRsph3oh3f2WSxJFjl3zblKpJPPiITbBRdsmqYBMB3x4CL1k MuiyvAylKQEUAihfy8BUjszvwmVQ9A6LPDf4X2AP20gL7mHKapHiHeuvI9Pa8IY4Kgys jCfg==
X-Gm-Message-State: AJIora+SyRjzHfxJSf3TSfF58wQ9zIXeDHZ2jJgTgyGeWA7mKT4LxsBQ uxPm792/E8PTWhVD49Qp0uDYxXzI3vl3xw==
X-Google-Smtp-Source: AGRyM1t/GADSsyZ+7P13rPsDRe4Wc8EiQ7HLUpNzlqPgRd0qO3FdyTZRt1sRZ2AViR0EcOtBorKkHg==
X-Received: by 2002:a0c:9c83:0:b0:473:442d:ad4 with SMTP id i3-20020a0c9c83000000b00473442d0ad4mr559018qvf.9.1658439561789; Thu, 21 Jul 2022 14:39:21 -0700 (PDT)
Received: from smtpclient.apple ([2601:86:101:11e0:7dfc:8a72:6b16:9b86]) by smtp.gmail.com with ESMTPSA id v33-20020a05622a18a100b0031f0b43629dsm2184556qtc.23.2022. (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 21 Jul 2022 14:39:21 -0700 (PDT)
From: Jonathan Lennox <jonathan.lennox@8x8.com>
Content-Type: multipart/alternative; boundary="Apple-Mail=_D6192B1C-8C31-4E6D-AEED-B99FBF0BA217"
Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3696.100.31\))
Message-Id: <4D0CCEDB-FFB8-4E16-9B3D-5E4020419B9F@8x8.com>
Date: Thu, 21 Jul 2022 17:39:20 -0400
Cc: draft-he-avtcore-rtcp-green-metadata@ietf.org
To: avtcore@ietf.org
X-Mailer: Apple Mail (2.3696.100.31)
Archived-At: <https://mailarchive.ietf.org/arch/msg/avt/_saT_RtsUUIDnbIlA3SvlvSVWeM>
Subject: [AVTCORE] Comments on draft-he-avtcore-rtcp-green-metadata
X-BeenThere: avt@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: Audio/Video Transport Core Maintenance <avt.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/avt>, <mailto:avt-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/avt/>
List-Post: <mailto:avt@ietf.org>
List-Help: <mailto:avt-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/avt>, <mailto:avt-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 21 Jul 2022 21:39:31 -0000

Hi - I read over draft-he-avtcore-rtcp-green-metadata in advance of the IETF meeting.

Some comments as an individual:

My first question is whether there is a freely-available (non-paywalled) version of the [GreenMetadata] spec?

In the absence of this, it is somewhat difficult to completely understand the semantics of the TSRR message as this document is currently written, so it might be useful to specify the semantics in full in this document, and cite [GreenMetadata] only informatively.

That said, I infer that the message's intended semantic is “this is the maximum resolution/frame rate I am interested in displaying at this time”.  Is this correct?  If so this seems like a useful semantic, and I can see how it could be used to save both energy and other resources.

A few more minor comments as an individual:

The FMT values you chose for your message are already assigned - please see https://www.iana.org/assignments/rtp-parameters/rtp-parameters.xhtml#rtp-parameters-9 <https://www.iana.org/assignments/rtp-parameters/rtp-parameters.xhtml#rtp-parameters-9> for the list of the currently-assigned values.  The next two free values are 11 and 12.  (There’s no need to repeat the assignments from RFC 4585 or 5104 in your document.)

The ability to specify a resolution or frame rate of 0, meaning “no video bitstream is requested”, seems to overlap in semantics with the PAUSE/RESUME semantics defined in RFC 7728, and also with various higher-level ways of turning video on and off; rather than have to specify how these mechanisms interact, it might be better for this specification to forbid values of 0.

Finally, the URL in the reference for [GreenMetadata] points to the ISO standard "ISO 5834-1:2019: Implants for surgery — Ultra-high-molecular-weight polyethylene — Part 1: Powder form”, which I suppose is indicative of the broad range of topics that ISO standardizes.  I suspect you instead meant to point at https://www.iso.org/standard/83674.html <https://www.iso.org/standard/83674.html>.

As a chair, my question is the usual one: if we standardized this, is there a community that would be interested in implementing and using it?