From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oo1-xc31.google.com (mail-oo1-xc31.google.com [IPv6:2607:f8b0:4864:20::c31]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 1472E3B29E for ; Fri, 31 Jan 2025 19:49:41 -0500 (EST) Received: by mail-oo1-xc31.google.com with SMTP id 006d021491bc7-5f89aa7a101so1057730eaf.2 for ; Fri, 31 Jan 2025 16:49:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1738370980; x=1738975780; darn=lists.bufferbloat.net; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=hNO9CsXScCbdQl+JRE34EYdxV+d0nHE4WwQC/zbXVBo=; b=a7hEnam4U/lmNXuQGcyUWIoqgPs9w798J4usYBgOFa9NTuhG+jukgn01MwFCKyOKye cs4D/CSBPTCFfJL5z17UYVCmrVb5rR5VtNP4TfyAxUtXadcbPvA87AKP7ZhGwSVBLcfj 8FnitNbnKMqVDcBlYx9vHJRiwMTOnxi9M2jmRWoS5pcriL6T36gf/8yGQX4K7lbsTuXx /XjSQ/AziknJlgHvSB5SkpzYAXhWwdpFJhc3yFF6RduI4o2KFdRPnuSewsY1jgL6nb40 QO8fNOcVNK4W4MJXZyZvQTkX5uR/UJOIgoUQhc2sTfiu0afYeE5mbnkMIwwxl5yyPU9a xdAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738370980; x=1738975780; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=hNO9CsXScCbdQl+JRE34EYdxV+d0nHE4WwQC/zbXVBo=; b=OnRpVXL+nKtYgWg2HVheGQfbvw6U7/9mTfs9CxVarB9E7Qs5eCw5s4F2yYjBgTqvHU TrsWB0Ck+h9f/XCgTi2bTIXJo+H9udh6Wwui3hAGO3byk6j9mMJpx2Ua0II4TnemO+j7 EwLixgXWvTYqDArkYmIM+S+s2YsHwweMjLg5/zroJLehN/ozr4l2+XhqaC7lObHtgwL3 f2mANxX1WflkFevU6GJqRYl+tbiR7eRKyxNxMExUHJ+pvm278Jb42h8s+btwNSKLCx8D 0Mv+Ev6YQbd0ePnoyaEU5GAHkEaQxAgtkctNPtx9QdXkaSLJd6WbBuSMWd8CI41I2Ca4 /VIw== X-Gm-Message-State: AOJu0Yz2sblGzjQm4DfIn7xRW7xxsjcU1TMYJiXR0ZT5LmSMjNsw1n+4 hpHSLF0nzgfOZq/iQLuQML35PQAVPUunTISjVzF1mjIlJKxkWGlDtR/eAatMGgFP0kM2zseKiCI bakVYhxvR4Mu3LF3fqF/gvhU7vyveaM6U X-Gm-Gg: ASbGncsu2oAJ0IT7PtwHo3S1s0MzsiNchOyJn4JU1Y8rloNP/yLnBffb9VvW3CN7AGe t8IN0Urf7b+aa/ZrByPqKT1s9/ZqGSS0u6RdNhrKV0C3ojgdioeRcmxZFSKT8HogW344AEmtSmF 3plT0bzxBWIqjSEZ/H2YJqKD1aFkskbg== X-Google-Smtp-Source: AGHT+IF11DQNtjWIAqmr9XOaEnDbqbhIPqf6AR152uJlSJCngh6bXu98GGyDNXBCdoV159ZrU3wgUngZSfkUxokrwz4= X-Received: by 2002:a05:6870:ff8c:b0:29e:70c7:a3eb with SMTP id 586e51a60fabf-2b32f099067mr7647966fac.7.1738370980252; Fri, 31 Jan 2025 16:49:40 -0800 (PST) MIME-Version: 1.0 References: <48F77C27-0E57-4F96-9BD8-238CC93342F8@gmail.com> In-Reply-To: From: Dave Taht Date: Fri, 31 Jan 2025 16:49:27 -0800 X-Gm-Features: AWEUYZn1iLBbd-uP9kJVW9A2MeTdRWhw4cBIq-CTKzdOYZHjGB0K3hZjIfHw7gM Message-ID: To: David Collier-Brown Cc: bloat@lists.bufferbloat.net Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [Bloat] Comcast & L4S X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Feb 2025 00:49:41 -0000 https://www.lightreading.com/cable-technology/comcast-wields-low-latency-as= -broadband-differentiator On Fri, Jan 31, 2025 at 4:40=E2=80=AFPM David Collier-Brown via Bloat wrote: > > What Comcast/L4S is doing was once called, by a Polish colleague, > "Peeing in the soup, so it smells more like me." > > --dave > > On 1/31/25 18:57, Dave Taht via Bloat wrote: > > Here are the positives: > > > > For the first time, a major ISP has deployed the PIE AQM on all > > traffic. Before now Comcast was only doing that on the upstream. > > That=C2=B4s 99.99% of all current comcast traffic getting an AQM on it.= WIN. > > > > The L4S side being enabled will also result in some applications > > actually trying to use it for cloud gaming. There is a partnership > > with valve, > > meta, and apple, that implies that we will perhaps see some VR and AR > > applications trying to use it. I look forward to a killer app. > > > > Negatives include explicit marking and potential DOS vectors as often > > discussed. I do feel that in order to keep up with the jonesies, > > we will have to add optional l4s marking to CAKE, which should > > outperform pie (mark-head), I just wish I knew what the right > > level was - at 100Mbit it seemed at 2ms was best. We also need to > > remove classic RFC3168 style marking and drop instead when the L4S bit > > is present - across the entire linux and BSD ecosystem. > > > > There was an abortive attempt last year to get dualpi, accecn, and > > prague into mainstream linux, but it stumbled over GSO handing, and > > has not been resubmitted. ACCECN seems to be making some progress. > > This makes it really hard to fool with this stuff. > > > > > > > > > > > > > > > > > > On Fri, Jan 31, 2025 at 5:27=E2=80=AFAM Sebastian Moeller via Bloat > > wrote: > >> Hi Rich, > >> > >> > >>> On 31. Jan 2025, at 14:20, Rich Brown via Bloat wrote: > >>> > >>> Google Alerts sent me this: https://www.webpronews.com/comcasts-laten= cy-leap-a-game-changer-in-network-performance/ > >>> > >>> Key quote: "Compatibility and Ecosystem: For L4S to have a significan= t impact, it requires an ecosystem where both the network infrastructure an= d the end-user devices support the standard..." > >>> > >>> Can anyone spell "boil the ocean"? :-) > >>> > >>> Or am I missing someting? > >> Well, the whole safety mechanisms in L4$ are laughably inadequate... t= his "design" essentially exposes a priority scheduler* without meaningful a= dmission control to the open internet. This is so optimistically naive that= it almost is funny again. I wish all the effort and hard work to make L4$ = happen, would have been put in a reasonable design... but at least I learne= d one of the IETF's failure modes, and that is at least something valuable = ;) > >> > >> > >> *) Just because something is not a strict preempting priority schedule= r does not make it a good idea to expose it blindly... a conditional priori= ty scheduler with e.g. L4$' weight share of 10:1 already can do a lot of h= arm. > >> > >> > >>> > >>> _______________________________________________ > >>> Bloat mailing list > >>> Bloat@lists.bufferbloat.net > >>> https://lists.bufferbloat.net/listinfo/bloat > >> _______________________________________________ > >> Bloat mailing list > >> Bloat@lists.bufferbloat.net > >> https://lists.bufferbloat.net/listinfo/bloat > > > > > -- > David Collier-Brown, | Always do right. This will gratify > System Programmer and Author | some people and astonish the rest > davecb@spamcop.net | -- Mark Twain > > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat --=20 Dave T=C3=A4ht CSO, LibreQos