[Moq] Re: Knowing the start of a Subgroup

Ian Swett <ianswett@google.com> Mon, 04 May 2026 02:38 UTC

Return-Path: <ianswett@google.com>
X-Original-To: moq@mail2.ietf.org
Delivered-To: moq@mail2.ietf.org
Received: from localhost (localhost [127.0.0.1]) by mail2.ietf.org (Postfix) with ESMTP id AEAFEE8809BC for <moq@mail2.ietf.org>; Sun, 3 May 2026 19:38:44 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ietf.org; s=ietf1; t=1777862324; bh=D1Ui1euGjfv5gpwctxh4Q0zRI2vVXgVSQKNRiHbSD9U=; h=References:In-Reply-To:From:Date:Subject:To:Cc; b=xopUuPMEKa8MVAU5MXa6NDTVQ6cZEcOVo3p/bt92EkprY/tBPSMg8YWxfMKpRTEG3 tyrjKQoiD6Hefk1HuGGh9UrSx7Wx8uJd9cCGLDAUPe15+pJgseUpD6qd/c7tKmvT9v aUHJvTusPFKjWVfxahajk6Uq77livb57MRuQRXGY=
X-Virus-Scanned: amavisd-new at ietf.org
X-Spam-Flag: NO
X-Spam-Score: -17.6
X-Spam-Level:
X-Spam-Status: No, score=-17.6 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, ENV_AND_HDR_SPF_MATCH=-0.5, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5, USER_IN_DEF_SPF_WL=-7.5] autolearn=ham autolearn_force=no
Authentication-Results: mail2.ietf.org (amavisd-new); dkim=pass (2048-bit key) header.d=google.com
Received: from mail2.ietf.org ([166.84.6.31]) by localhost (mail2.ietf.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id M9sW3osY31BY for <moq@mail2.ietf.org>; Sun, 3 May 2026 19:38:44 -0700 (PDT)
Received: from mail-dl1-x1235.google.com (mail-dl1-x1235.google.com [IPv6:2607:f8b0:4864:20::1235]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail2.ietf.org (Postfix) with ESMTPS id 6788AE8809B0 for <moq@ietf.org>; Sun, 3 May 2026 19:38:44 -0700 (PDT)
Received: by mail-dl1-x1235.google.com with SMTP id a92af1059eb24-12dbd0f7ecaso8277786c88.0 for <moq@ietf.org>; Sun, 03 May 2026 19:38:44 -0700 (PDT)
ARC-Seal: i=1; a=rsa-sha256; t=1777862323; cv=none; d=google.com; s=arc-20240605; b=OHFH/nLLGLSYU7D+W37lrPTy31Y5SdXJJY76mlvVn4nUBPpxHRvHxoY/j2I1FxGyBb ifmHgeUTbhh+dN+FExodGSh+kKlh+2qce85PxZovvu/jN4kJ8EPsslEElFYNU3GGX9K2 lo4z1hnfEm7UlrI11B6YwH8g/uj9pC3kLpM7ObA7iG4a46UVbWG0HlaW4Qh9sfVOcnYC ATv/V62CBndqMqNW9yDAJVwrATW6EiS715KZa11+Z5dh+Mb+tvsqKrj1RkmJAkTctWOQ BswNU1AMrvBP1QTBRBZIQtd4Po3JfWFKcKsZLjU3Z/e+EQDjAUVH0Kmt3IuWyRI5IaPN CsrQ==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20240605; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:dkim-signature; bh=3xwCguNsC4tNS2kPkSB1qaKA4IYvIGSJUIaAKYdIxuI=; fh=aRScOuuhdEDK6Xedi6I4ZjxKY00lsKWeuJ0Ml6o0TK0=; b=DT/9Ns5gJiVRRME81UgwKrYAgS6DtLmIkaa30zx3wtfpwa0NMPZpoPOhgXi9AWLED7 pIWyRG7P9BSesjb434ZFXpuHvcmQwUo9okETHde+4KO4LQJYXzBe/G+rd/0t3CHhDOTf zjkdx6QxnAI77rm+C/yLrL4NOCgQ9f+zbBSMxIg6T58QhP2hkfKRuZWo/r8T48+Hlwb8 CKVTuke0j4GTJdMRd4c++gsXu1ctICquxeWycqjY8AnV3Qv3NFTW6QfOOZXeldDM9s+u lTUDdotrnhnQ+qMgLO20BVKoSyj//m+ybfMlmRN8ZqoRlHQEgOntKm/+zDxBCm6hj1NI Pfew==; darn=ietf.org
ARC-Authentication-Results: i=1; mx.google.com; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777862323; x=1778467123; darn=ietf.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=3xwCguNsC4tNS2kPkSB1qaKA4IYvIGSJUIaAKYdIxuI=; b=ks0OHD2hgU1caruAwWwZbPhhHIotdUYh9EqcZyhnRlU3FYoAaa2OU31CFao6bZXOy0 cno7aWDx6+Ahu1piKyoSWHSxdeQLCyULKupq/LjqY9+pQxoGwT71a46Ku+6j1ENhiHnp onM9KayiQkpQ112cP3oNMOnPyzxKRXs/MrKJLKQeg5xnTPvpoiBVFJiSQss94y4q76lC 4uV2cGoRmwUxYmHXLK3vYqaJb/OVQtdAxaXwsPLKgCA1UhhenSqEWRSKDwFqtuU5tbMB GlIPUv+3SYB3jgz3I7bXD/B8EP0IftYOJhRQmh2yTH2188Dguci7ULhEx41Z46vF1xjN XwDg==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777862323; x=1778467123; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3xwCguNsC4tNS2kPkSB1qaKA4IYvIGSJUIaAKYdIxuI=; b=T+O8vlXHBveoRBBuwAVe2D6Emy8MKsXP53l7yWLUGgDArvUTdo910mJAIaN63WUITH 1AdODQv5V+F1VwdqM/ej5kCrTRblIjiJzXH4OfStiMXgUU7k540NjivqZlgT+3yRsnfa HLETlZHYL2SAN8wY1LfdmqINR3cGYdDNxZVU5KSFAJCNFRbxAZ40n42rx5IQ0vzI1/gU Gkh2zfsGZSkCWWWIp7yLeVBmtAC5A/xkzJkQmLNta0vbm+oGBIOy9MYrlEap6kDQFHT4 lh9n56XoUQ+AfhEHM+sQgMLKtReeEYmJMr237xuJQdNtcy5s1n40iHJTHHzGgmTzc1EG 7XzA==
X-Forwarded-Encrypted: i=1; AFNElJ+nGLKcb3LSdyOxkcV6+3pvg8qDwswXPUNkFUR0ScbXp1+OvN6xkA1UZUrdYNieE0W9EZE=@ietf.org
X-Gm-Message-State: AOJu0YzfbqhPyVB2YtjExcgRvsRfDlyy+84FZXCqGSzXloH3sqNKFI07 AD+M6jg56a37Z0cLBVJarMmGF916wcDyenZuE83txYBRioud1Nc/YgrdHSMLDI7TyVmUzQSRkb4 muApLmDgOX6lT0Gb0mskEyGP71jLKNwD1kU228lgFcZqwvkzMbpVDQ/U/
X-Gm-Gg: AeBDiesludmn8Sos0ernUsOTiYO18tA0xlV7EXyFaS8Al12rLbHonYEaGtGak/dteGw Jl/gNFPnkNrzmdFQTUPlr2aTWWQEvr72D5Q+pKGIsUcVPdqonVBFXcXz4wtUF6zs2a+LJaqHJEu Gxt2eaWHTmpFpS5f7Maynop31HHBnyn+RaCryrG16Gb9LpCBRbOlMsjcKkYpNkIOjLQaVRKJ7wj nrZAYfvwS606vfpC+IKA4KgNDAYh5uVm3Y0wl5C9STD51W9Wb/Oj8uVRCpvO7ddxxoKjAdM8rUL yvQxbYMCsft9bgGlr39PB4swCxfHkQ0aCvtDmn2LpeeFc4WrCSoOL/Vx7cSjA9KSRN2S/K8Z/dI VuBAYAqKLHB7X
X-Received: by 2002:a05:7022:61a:b0:12b:ec67:3529 with SMTP id a92af1059eb24-12dfd7fc727mr3515348c88.14.1777862322624; Sun, 03 May 2026 19:38:42 -0700 (PDT)
MIME-Version: 1.0
References: <CAKcm_gPTt1pcHEfyHQYeqGHL6NHYTb7RkZKHoaR-7ofZg=yoTg@mail.gmail.com> <2C11C671-0812-4152-9804-03C80372B164@iii.ca> <FRWPR07MB106246C776844E65C4F57FE3795352@FRWPR07MB10624.eurprd07.prod.outlook.com> <CAKcm_gORGM_mGyNkC0UQYWEwoFMWneBZDMnwgGfWt22TiJBo0A@mail.gmail.com> <AA79BAD7-825A-45F8-BDFF-26AF339A8FFB@iii.ca>
In-Reply-To: <AA79BAD7-825A-45F8-BDFF-26AF339A8FFB@iii.ca>
From: Ian Swett <ianswett@google.com>
Date: Sun, 03 May 2026 22:38:30 -0400
X-Gm-Features: AVHnY4IZaHsJvgavCqtVDdzCx2gZVujJh1pi2PQvrMv8PE9iZoRJg0ptIMPMyHs
Message-ID: <CAKcm_gO6fULDakmdYe7m_irxOtaydSRDymh8Se0EYsEMAOj6xw@mail.gmail.com>
To: Cullen Fluffy Jennings <fluffy@iii.ca>
Content-Type: multipart/alternative; boundary="0000000000003439d70650f4d418"
Message-ID-Hash: JOQSXCST3KDVDAAJ5N5J4ILN7EPNNMWX
X-Message-ID-Hash: JOQSXCST3KDVDAAJ5N5J4ILN7EPNNMWX
X-MailFrom: ianswett@google.com
X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header
CC: Magnus Westerlund <magnus.westerlund=40ericsson.com@dmarc.ietf.org>, MOQ Mailing List <moq@ietf.org>
X-Mailman-Version: 3.3.9rc6
Precedence: list
Subject: [Moq] Re: Knowing the start of a Subgroup
List-Id: Media over QUIC <moq.ietf.org>
Archived-At: <https://mailarchive.ietf.org/arch/msg/moq/dL1-WD_iTNa4WR-dHfZrHPKhNXA>
List-Archive: <https://mailarchive.ietf.org/arch/browse/moq>
List-Help: <mailto:moq-request@ietf.org?subject=help>
List-Owner: <mailto:moq-owner@ietf.org>
List-Post: <mailto:moq@ietf.org>
List-Subscribe: <mailto:moq-join@ietf.org>
List-Unsubscribe: <mailto:moq-leave@ietf.org>

Thanks for all the responses, particularly Mo's detailed response.

I think we should move forward with the bitfield approach in #1618.

I don't love that both Subgroup ID and Priority are ways of prioritizing
Objects within a Group.  At some point we agreed that priority should only
be a single byte. However, with Subgroup ID as well as priority, we now
have a huge space.  In practice, it probably doesn't matter, and I'm just
overthinking this.  But it seems like there should be a way to
simplify this part of the Object model without restricting any real-world
usecases.

Thanks, Ian

On Fri, May 1, 2026 at 6:14 PM Cullen Fluffy Jennings <fluffy@iii.ca> wrote:

>
>
> > On Apr 30, 2026, at 9:08 AM, Ian Swett <ianswett@google.com> wrote:
> >
> >
> > If we go with the bitflag approach (#1618), are people ok with requiring
> it be set on the first Object in the Subgroup?  Requiring it gives the
> feature a lot more value IMO.
>
>
> Yes, that makes sense to me.