From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-x72a.google.com (mail-qk1-x72a.google.com [IPv6:2607:f8b0:4864:20::72a]) (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 000003CB38 for ; Fri, 19 Jan 2024 02:52:07 -0500 (EST) Received: by mail-qk1-x72a.google.com with SMTP id af79cd13be357-783182d4a0aso38405385a.2 for ; Thu, 18 Jan 2024 23:52:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1705650727; x=1706255527; darn=lists.bufferbloat.net; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=6zdXB+hIduaTTIJ1PaQP56i4n2mhJPZnhHFIYx68y4w=; b=AhVP1zilVO08e4djp1chTIwTkbICiDvUqb0dHkAaY8UAO+pADzwnVqdMprHP5QhKsw qmYdJiAsi/ZsrQ43xEQpnNvmVHIxsx+y5pikIImcOC4r8SrndYKASkx3BqABtY9qZpku bK46SdXYO3BOBXdfWFpz6yu3YkwU2LJAZSSRuhRro3/oM+qdN/SjmZwYIuU+NtSykYdv XD1w1agG527k4NMMCqyU2R2hyano1Q/NLuwGkK/cDjApQUFtzLwi3ADyVXIJVmAD7u2V I+XaV2unKT3In2qPi+tXAlTyp7PphThD9Q1Nq49sTUbgFa6OBCpkdxhsA8/S2cNSrOsx iHkA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705650727; x=1706255527; h=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=6zdXB+hIduaTTIJ1PaQP56i4n2mhJPZnhHFIYx68y4w=; b=KryrwrsPgaThXT9kIQ5FgFa+QEY/XgLDDZdT7WxoqVDM0t2In7LygY8LNe+oU0i5aP rOIGQdKSx5bgWS17DeHN1S77WLWarZgO1/Bv5BggHTVBaljs7NwzEb/Ipn8gRLWmQUs/ RIxnCb6e0iR7bfYAQipR+U5BCRm9OUPhEwPQ1JYocLPk293mtMmlwpcryoVDy+oi6j73 g4BpyHnuiSTRTjdw31QRBH5Vpd/Ymw/qCjqg1jR30oyBxfOtWNl0qzAf7POUCPqXPPyH qfEmqfxjefpAlqfFVm/2pRHgWnbPc/vcR2JgWW2YhzO2PQKDtWOleITcIx8bNhxwAi8j QztQ== X-Gm-Message-State: AOJu0YzHRdWvHCSo/WoH23v+593zgx70QL4F0hrk0B5oP+1e/sSQ+d78 I3Hhq94WJOsGJh9ToWJLnCQL13ETM0Ia1Vn7K7A4pBS/YN50rBQxekXXp5KTFeuDfJMthTspIsW Qy0Yx2H3VIdLx0w+a6f081dPcUC7JvLe/ X-Google-Smtp-Source: AGHT+IE71ao7R62UsAcDZ4YpKmVUNlZtWiSW18xO8syuSBSK6aojW9rLg/kWqGZl5EEL6f0unfPNFmm9abt9nJOCGK8= X-Received: by 2002:ae9:e212:0:b0:783:2e22:5743 with SMTP id c18-20020ae9e212000000b007832e225743mr871366qkc.92.1705650727276; Thu, 18 Jan 2024 23:52:07 -0800 (PST) MIME-Version: 1.0 References: <7D4F20E7-F4A8-44C2-BDF5-A666CF7C94FB@pch.net> In-Reply-To: <7D4F20E7-F4A8-44C2-BDF5-A666CF7C94FB@pch.net> From: Frantisek Borsik Date: Fri, 19 Jan 2024 08:51:31 +0100 Message-ID: To: =?UTF-8?Q?Network_Neutrality_is_back=21_Let=C2=B4s_make_the_technical_asp?= =?UTF-8?Q?ects_heard_this_time=21?= Content-Type: multipart/alternative; boundary="000000000000b5d520060f47c1cf" Subject: Re: [NNagain] are you Bill Woodcock? X-BeenThere: nnagain@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: =?utf-8?q?Network_Neutrality_is_back!_Let=C2=B4s_make_the_technical_aspects_heard_this_time!?= List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Jan 2024 07:52:08 -0000 --000000000000b5d520060f47c1cf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Looking forward to join the upcoming IXP chat, Bill! All the best, Frank Frantisek (Frank) Borsik https://www.linkedin.com/in/frantisekborsik Signal, Telegram, WhatsApp: +421919416714 iMessage, mobile: +420775230885 Skype: casioa5302ca frantisek.borsik@gmail.com On Fri, Jan 19, 2024 at 8:26=E2=80=AFAM Bill Woodcock via Nnagain < nnagain@lists.bufferbloat.net> wrote: > > > > On Jan 19, 2024, at 08:14, Sebastian Moeller wrote: > >> On 18. Jan 2024, at 23:38, Bill Woodcock via Nnagain < > nnagain@lists.bufferbloat.net> wrote: > >> So, if one Internet user wants to talk to another Internet user, > generally they hand off their packet to an Internet service provider, who > takes it to an exchange, and hands it off to another Internet service > provider, who delivers it to the second user. When the second user wants > to reply, the process is reversed, but the two Internet service providers > may choose a different exchange for the hand-off: since each is > economically incentivized to carry the traffic the shortest possible > distance (to minimize cost, speed x distance =3D cost), the first ISP wil= l > always choose the IXP that=E2=80=99s nearest the first user, for the hand= -off, > leaving the second ISP a longer distance to carry the packet. Then, when > their situations are reversed, the second ISP will choose the IXP nearest > the second user, leaving the first ISP to carry the packet a longer > distance. > > > > I would propose a slight modification, "each is economically > incentivized to carry the traffic the shortest possible distance" is not > free of assumptions... namely that the shortest path is the cheapest path= , > which is not universally true. > > Correct. That=E2=80=99s a simplification of a complex field where distan= ce and > cost are frequently intermingled, and routing decisions are typically bas= ed > on latency, overridden by cost as a matter of policy. However, in a > simplified or idealized case, if speed is held constant, distance and cos= t > scale together, so they are usually held to be interchangeable in > decision-making in the general case. Speed x distance =3D cost. > > > My personal take is "routing follows cost" that is it is money in the > end that steers routing decisions > > Yes, exactly. > > The primary case in which routes follow a cost that differs from distance > is in the preference for distant downstream transit over nearby peers, an= d > distant peers over nearby upstream transit. Though it=E2=80=99s uncommon= in > networks of small geographic scale, most global-scale networks do this, a= nd > it=E2=80=99s the cause of many routing problems and loops. > > > ...at least once we include paid peering... > > That=E2=80=99s a marketing euphemism for transit. > > > My ISP aggregates its customers in a handful of locations in Germany, > Hamburg in my case while I actually live a bit closer to Frankfurt than > Hamburg, so all traffic first goes to Hamburg even traffic to Frankfurt > (resulting in a 500-600 Km detour), I assume they do this for economic > reasons and not just out of spite ;) > > Essentially all mobile network operators do this. It=E2=80=99s generally= a matter > of incompetence and lack of competition, rather than spite or economic > reasons. > > > Now, maybe the important point is, this does not involve IXPs so might > be an orange to the IXP apple? > > Yes, only indirectly. Most of what you=E2=80=99re discussing involves no= n-optimal > outbound IXP selection, one quarter of the round-trip path. Very real > issues, but not anything an IXP or receiving-side ISP can do much about > without second-guessing routing decisions to an impractical degree. > > -Bill > > _______________________________________________ > Nnagain mailing list > Nnagain@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/nnagain > --000000000000b5d520060f47c1cf Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Looking forward to join the upcoming IXP chat, Bill!
<= br clear=3D"all">
All the best,

Frank

Frantisek (Frank) Borsik

=C2=A0=

https://www.linkedin.com/in/frantisekborsik

Signal, Teleg= ram, WhatsApp: +421919416714=C2=A0

iMessage, mobile: +420775230885=

Skype: casioa5302c= a

frantisek.borsik@gmail.com

=


<= div class=3D"gmail_quote">
On Fri, Jan= 19, 2024 at 8:26=E2=80=AFAM Bill Woodcock via Nnagain <nnagain@lists.bufferbloat.net> wrot= e:


> On Jan 19, 2024, at 08:14, Sebastian Moeller <moeller0@gmx.de> wrote:
>> On 18. Jan 2024, at 23:38, Bill Woodcock via Nnagain <nnagain@lists.b= ufferbloat.net> wrote:
>> So, if one Internet user wants to talk to another Internet user, g= enerally they hand off their packet to an Internet service provider, who ta= kes it to an exchange, and hands it off to another Internet service provide= r, who delivers it to the second user.=C2=A0 When the second user wants to = reply, the process is reversed, but the two Internet service providers may = choose a different exchange for the hand-off: since each is economically in= centivized to carry the traffic the shortest possible distance (to minimize= cost, speed x distance =3D cost), the first ISP will always choose the IXP= that=E2=80=99s nearest the first user, for the hand-off, leaving the secon= d ISP a longer distance to carry the packet.=C2=A0 Then, when their situati= ons are reversed, the second ISP will choose the IXP nearest the second use= r, leaving the first ISP to carry the packet a longer distance.
>
> I would propose a slight modification, "each is economically ince= ntivized to carry the traffic the shortest possible distance" is not f= ree of assumptions... namely that the shortest path is the cheapest path, w= hich is not universally true.

Correct.=C2=A0 That=E2=80=99s a simplification of a complex field where dis= tance and cost are frequently intermingled, and routing decisions are typic= ally based on latency, overridden by cost as a matter of policy.=C2=A0 Howe= ver, in a simplified or idealized case, if speed is held constant, distance= and cost scale together, so they are usually held to be interchangeable in= decision-making in the general case.=C2=A0 Speed x distance =3D cost.

> My personal take is "routing follows cost" that is it is mon= ey in the end that steers routing decisions

Yes, exactly.

The primary case in which routes follow a cost that differs from distance i= s in the preference for distant downstream transit over nearby peers, and d= istant peers over nearby upstream transit.=C2=A0 Though it=E2=80=99s uncomm= on in networks of small geographic scale, most global-scale networks do thi= s, and it=E2=80=99s the cause of many routing problems and loops.

> ...at least once we include paid peering...

That=E2=80=99s a marketing euphemism for transit.

> My ISP aggregates its customers in a handful of locations in Germany, = Hamburg in my case while I actually live a bit closer to Frankfurt than Ham= burg, so all traffic first goes to Hamburg even traffic to Frankfurt (resul= ting in a 500-600 Km detour), I assume they do this for economic reasons an= d not just out of spite ;)

Essentially all mobile network operators do this.=C2=A0 It=E2=80=99s genera= lly a matter of incompetence and lack of competition, rather than spite or = economic reasons.

> Now, maybe the important point is, this does not involve IXPs so might= be an orange to the IXP apple?

Yes, only indirectly.=C2=A0 Most of what you=E2=80=99re discussing involves= non-optimal outbound IXP selection, one quarter of the round-trip path.=C2= =A0 Very real issues, but not anything an IXP or receiving-side ISP can do = much about without second-guessing routing decisions to an impractical degr= ee.

=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 -Bill

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