From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) (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 127823CB37 for ; Fri, 28 Oct 2022 20:34:53 -0400 (EDT) Received: by mail-wm1-x329.google.com with SMTP id t4so4081072wmj.5 for ; Fri, 28 Oct 2022 17:34:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:cc:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=ePh6bCJVBZhF22+BcOkcLVDH4/49YgrmBycQXqShQnI=; b=pDmxFoJnq8sMZNRx7XmyF1+6AC25IQ5o0HLc3CZ08GUvbIGJJf9OakrU/oa33aCv18 9yP/4V76qj0OrdJWKED+zKuLn22z6G4L2/Yol+CkONmXZIKTOLMBaOMAqt5lz9ejAoQb yoVki9niLygz4QPObaQ+uO6f/2QxB5kEb+Bk7x4gb5rEJG2ghgMWPW62EKzQXxsqSQ8c DGfZhxX7QmXeNrpyK+4qA83Gs1RjQRFMrRHY31cVEU03t6H4PIhTNB0of/wnR537QcJq fXEZCHCDNAo4KcWWaR9BVPA525l04Uf14I2vnXQVHE+9hagguWftUccZ9YJSiluLXpcT 3vVA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:cc: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=ePh6bCJVBZhF22+BcOkcLVDH4/49YgrmBycQXqShQnI=; b=WlgMu03gM7rmbJSDzr1khlDjckw97K8YPh3J+WlH1YcnUjCOI5/Q1eY8sxjC3hXYBZ K6noJenCprJHxU3MaBfqM+fBlPfnS4+ornf8O1h+Fo4Y1dCh/lHeFIH+4f0wO+VSXHsK J+wjLDjD7ANZ1Jnx9XPIBPL0DmGgg/qBA6BB919P6QQRtxMDOzpjQyBgKx0HhhNgJBx4 2cthaK9ZLDh4X7IYwd7fhbP+Kqz2snvAHypJvW3ujHvvnEpqUKAaBgaLq7G2JOhViKlX Y0Vzx0we+5TJURag37G068ymFLKkkmlpGTMNsGtopaJnzYiZbXMTQj0z+NuTPG35P3xM Cw7w== X-Gm-Message-State: ACrzQf2i0CtUXR0CKLD9BZy3FSEhhA7GW4JGe2I2+AQ+UDmvEyCF+4B8 p5olT9MCh0SPwWIz1/taLVKKrAA18Fq8bEAcoO4o6uoFEZ0= X-Google-Smtp-Source: AMsMyM4p2dI0JxpV/10sas66OMDToNx/u4k3HmfsinBFVIMY4Ny9dRPaZE4zS8iVDu4hn+PyykarLgSbzx2xR93W4aw= X-Received: by 2002:a7b:c3c4:0:b0:3c4:785a:36d7 with SMTP id t4-20020a7bc3c4000000b003c4785a36d7mr11316818wmj.138.1667003691004; Fri, 28 Oct 2022 17:34:51 -0700 (PDT) MIME-Version: 1.0 References: <87sfj7vczj.wl-jch@irif.fr> In-Reply-To: From: Dave Taht Date: Fri, 28 Oct 2022 17:34:39 -0700 Message-ID: Cc: libreqos@lists.bufferbloat.net Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [LibreQoS] routing protocols and daemons X-BeenThere: libreqos@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Many ISPs need the kinds of quality shaping cake can do List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 29 Oct 2022 00:34:53 -0000 Taking juliusz off the cc for a sec. He's the author of a lot of cool stuff: https://www.rfc-editor.org/rfc/rfc8965 being one of them, but I first got to know him via the polipo web proxy... Anyone ever use tha= t? I also thought his work on continuation passing C (CPC https://www.irif.fr/~jch/research/ ) was way, way ahead of its time. One of his students wrote the then-fastest torrent server... and you can see reflections of this work in modern frameworks in tokio and elsewhere. I switched to his galene.org videoconferencing server early on in the pandemic and have never looked back. On Fri, Oct 28, 2022 at 5:01 PM Dave Taht wrote: > > On Fri, Oct 28, 2022 at 2:45 PM Juliusz Chroboczek wrote: > > > > > found babel, corresponded with (and frankly thoroughly annoyed) the > > > author, > > > > Being said author, I can confirm that you did thoroughly annoy me. But > > then, you also made me think. > > I'm glad, ultimately, we also drank, and I'll always remember (somewhat > blurrily) the day/night of our toasts to the builders of Notre-Dame. > > earlier on in this thread, herbert listed his complaints about OSPF, > if you have a spare moment, have you ever had any deep thoughts about > it? > > --snip snip-- > Dijkstra's algorithm remains a very natural approach to mapping a > graph (I've waxed lyrical about it in various book/article/blog posts > over the years in the game-dev world), so I find it a very comfy way > to model the underlying network. Very easy to reason "this will go > that way". > > So what's bad about it? > > * ECMP is equal; if you have routes with different costs it will only > use the lowest cost - it won't try and "mesh" some of the traffic in > other directions. Likewise, if you have two equal routes - and one of > them is running at a low capacity - you wind up only utilizing twice > the capacity of the slowest link. You're often better off dropping the > link over the degraded circuit (hence "carrier drop" features on > various radios). > * OSPF has no idea what the capacities of various links are. It'll use > the shortest cost route, and leave the details up to the lower layers > of the stack. > > There have been various attempts to integrate capacity into network > design, and I've yet to see one that holds up well on a multi-vendor > network. If you ask a Ubiquiti Rocket AC Gen2 its capacity, it'll > often give you some nice big number - but it'll stall out far before > that number. The Force 400C link we just put up doesn't even try to > estimate its capacity. So multi-vendor mesh routing tends to be > problematic, because the advertised capability of "we'll utilize > everywhere you have capacity" tends to get snarled up in figuring out > what the capacity is. I understand Teragraph is supposed to do better > there. MPLS traffic engineering was originally announced as solving > this one, too! I don't see a lot of hope for capacity-aware routing > protocols taking off, but I imagine we'll get a few new ones announced > and then quietly forgotten as before. > > And lastly: once your network gets really big, OSPF tables can get too > large - and you're stuck either dividing your OSPF zones and/or using > some BGP in interior mode. You can mitigate this with some careful > design. > -- unsnip -- > > I don't suppose you have ever had any ideas to how to improve things? > > > > > > > Babel is so simple that toke wrote a near complete implementation fro= m > > > the spec, in python, during a string of extremely boring IETF > > > meetings, over the course of a week. He later took on the bird port. > > > > This is not correct. Babel was first reimplemented in Python during tw= o > > nights during an IETF meeting by Markus Stenberg. As to Toke, he did t= he > > BIRD reimplementation in C during a Battlemesh meeting, and it took him > > a whole four days. I later did a minimal implementation in C, which > > compiled to 20kB of x86 code. > > You're working on galene, now, primarily? How's android treating you? > > > > > > I forget what happened to toke's python version). > > > > Markus Stenberg's. It's still available, but fairly obsolete due to > > advances in babeld and BIRD. > > > > https://github.com/fingon/pybabel > > yea! > > > > Althea is using babel and fq_codel in their blockchain routing thing > > > (I reserve comment), and I don't know where else, besides as part of > > > wireguard tunnels, babel is being used today. > > > > Now that Babel is no longer a legitimate research project, the main use= r > > and main source of funding for Babel are Nexedi, who use it in their > > distributed cloud > > > > https://www.nexedi.com/ > > If you can stomach it, I have a copy of althea's most current preso, > which I can send under separate cover. They scored 15 out of a 100 on > a funding round with it, but there babel and fq_codel were, with an > rtt metric on page 16... > > At least they leave breadcrumbs back to where the actual good ideas > came from. Many others in web3 haven't. > > > > > But I agree with you, Dave, Babel did not take over the world. The mai= n > > reason, I suspect, is that OSPF is very good, and that most people are > > happy enough with it. > > Everything can be improved. > > > Notwithstanding that, we're still maintaining both the standalone babel= d > > and Toke's BIRD module, and we've been busy extending the protocol with > > source-specific routing, with v4-via-v6 routing, with MAC protection. > > I am so in love with v4 via v6. It's just having to wait 6+ years for > places like mikrotik to ship it that I can't stand. > > > > > -- Juliusz > > > -- > This song goes out to all the folk that thought Stadia would work: > https://www.linkedin.com/posts/dtaht_the-mushroom-song-activity-698136666= 5607352320-FXtz > Dave T=C3=A4ht CEO, TekLibre, LLC --=20 This song goes out to all the folk that thought Stadia would work: https://www.linkedin.com/posts/dtaht_the-mushroom-song-activity-69813666656= 07352320-FXtz Dave T=C3=A4ht CEO, TekLibre, LLC