Paul- You said: "... would decide to configure MPLS paths between Chicago and distant international locations ..." AS3128 runs MPLS and it's probable someone might correct me here, but for a IGP backbone area I think it's common for there to be a full mesh of LSPs via either LDP, RSVP, SR etc. AS3128 is a small regional and we operate in that way across 60+ nodes. I don't know if it's common for someone with a global footprint like 1299 to have a contiguous global MPLS backbone, but the point of my reply was to say it's not impossible to think 1299 has a global MPLS mesh between major POPs. -Michael
-----Original Message----- From: NANOG <nanog-bounces+michael.hare=wisc.edu@nanog.org> On Behalf Of PAUL R BARFORD Sent: Tuesday, January 18, 2022 8:16 AM To: Saku Ytti <saku@ytti.fi> Cc: Esteban Carisimo <esteban.carisimo@northwestern.edu>; nanog@nanog.org; Fabian E. Bustamante <fabianb@cs.northwestern.edu> Subject: Re: Long hops on international paths
Hello Saku,
Thank you for the summary. We're clear about the fact that what we're seeing are MLPS paths - that was not in question. What we are not clear about and the reason for the post is why the provider - zayo.telia in this case - would decide to configure MPLS paths between Chicago and distant international locations. We assumed we would see hops in traceroute between Chicago and coastal locations and then hops that transited submarine infrastructure followed by hops to large population centers.
Regards, PB ________________________________
From: Saku Ytti <saku@ytti.fi> Sent: Tuesday, January 18, 2022 12:50 AM To: PAUL R BARFORD <pb@cs.wisc.edu> Cc: Lukas Tribus <lukas@ltri.eu>; Esteban Carisimo <esteban.carisimo@northwestern.edu>; nanog@nanog.org <nanog@nanog.org>; Fabian E. Bustamante <fabianb@cs.northwestern.edu> Subject: Re: Long hops on international paths
1) all (meaning all hitting the zayo.telia) your traceroutes originate from University in Chicago 2) the zayo.telia device is physically close to the university 3) we should expect physically close-by backbone device to be present in disproportionate amount of traceroutes 4) almost certainly zayo.telia is imposing the MPLS label of TTL 255, _NOT_ copying IP TTL, therefore until MPLS label is popped, TTL is not expiring. I.e. you are seeing ingressPE and egress PE ot Telia, you are not seeing any P routers.
This is not esoteric knowledge, but a fairly basic Internet concept. I am worried you are missing too much context to produce actionable output from your work. It might be interesting to see your curriculum, why this confusion arose, why it seems logical that the reason must be that almost all waves are terminated there, because it would not seem logical for people practising in the field who have even cursory understanding, this implies problems in the curriculum.
On Tue, 18 Jan 2022 at 07:21, PAUL R BARFORD <pb@cs.wisc.edu> wrote:
Please find the examples for the case of Telia below.
FROM jfk-us (jfk-us.team-probing.c008820.20201002.warts.gz)
traceroute from 216.66.30.102 (Ark probe hosted in New York City, NY, US.
No AS info found) to 223.114.235.32 (MAXMIXD: Turpan, CN)
1 216.66.30.101 0.365 ms
2 62.115.49.173 3.182 ms
3 *
4 62.115.137.59 17.453 ms [x] (chi-b23-link.ip.twelve99.net., CAIDA-
GEOLOC -> Chicago, IL, US)
5 62.115.117.48 59.921 ms [x] (sea-b2-link.ip.twelve99.net., RIPE-IPMAP ->
Seattle, WA, US)
6 62.115.171.221 69.993 ms
7 223.120.6.53 69.378 ms
8 223.120.12.34 226.225 ms
9 221.183.55.110 237.475 ms
10 221.183.25.201 238.697 ms
11 221.176.16.213 242.296 ms
12 221.183.36.62 352.695 ms
13 221.183.39.2 300.166 ms
14 117.191.8.118 316.270 ms
15 *
16 *
17 *
18 *
19 *
FROM ord-us (ord-us.team-probing.c008820.20201002.warts.gz)
traceroute from 140.192.218.138 (Ark probe hosted in Chicago, IL, US at
Depaul University-AS20120) to 109.25.215.237 (237.215.25.109.rev.sfr.net., MAXMIXD: La Crau, FR)
1 140.192.218.129 0.795 ms
2 140.192.9.124 0.603 ms
3 64.124.44.158 1.099 ms
4 64.125.31.172 3.047 ms
5 *
6 64.125.15.65 1.895 ms [x] (zayo.telia.ter1.ord7.us.zip.zayo.com.,
CAIDA-GEOLOC -> Chicago, IL, US)
7 62.115.118.59 99.242 ms [x] (prs-b3-link.ip.twelve99.net., CAIDA-
GEOLOC -> Paris, FR)
8 62.115.154.23 105.214 ms
9 77.136.10.6 119.021 ms
10 77.136.10.6 118.830 ms
11 80.118.89.202 118.690 ms
12 80.118.89.234 118.986 ms
13 109.24.108.66 119.159 ms
14 109.25.215.237 126.085 ms
traceroute from 140.192.218.138 (Ark probe hosted in Chicago, IL, US at
Depaul University-AS20120) to 84.249.89.93 (dsl-tkubng12-54f959- 93.dhcp.inet.fi., MAXMIXD: Turku, FI)
1 140.192.218.129 0.243 ms
2 140.192.9.124 0.326 ms
3 64.124.44.158 0.600 ms
4 *
5 *
6 64.125.15.65 1.792 ms [x] (zayo.telia.ter1.ord7.us.zip.zayo.com.,
CAIDA-GEOLOC -> Chicago, IL, US)
7 62.115.123.27 121.199 ms [x] (hls-b4-link.ip.twelve99.net., CAIDA-
GEOLOC -> Helsinki, FI)
8 *
9 141.208.193.190 127.723 ms
10 84.249.89.93 139.051 ms
traceroute from 140.192.218.138 (Ark probe hosted in Chicago, IL, US) to
193.28.231.50 (MAXMIXD: None, HU)
1 140.192.218.129 0.240 ms
2 140.192.9.124 0.333 ms
3 64.124.44.158 0.648 ms
4 *
5 64.125.25.75 0.752 ms
6 64.125.15.65 1.877 ms [x] (zayo.telia.ter1.ord7.us.zip.zayo.com.,
CAIDA-GEOLOC -> Chicago, IL, US)
7 62.115.119.39 123.952 ms [x] (bpt-b2-link.ip.twelve99.net., **I suspect
it is in Budapest, HU**)
8 62.115.39.122 117.171 ms
9 88.151.96.148 117.202 ms
10 88.151.96.213 124.787 ms
11 *
12 *
13 *
14 *
15 *
traceroute from 140.192.218.138 (Ark probe hosted in Chicago, IL, US at
Depaul University-AS20120) to 152.195.4.11 (MAXMIXD: Los Angeles, CA, US)
1 140.192.218.129 0.224 ms
2 140.192.9.124 0.545 ms
3 64.124.44.158 0.640 ms
4 *
5 *
6 64.125.15.65 1.786 ms [x] (zayo.telia.ter1.ord7.us.zip.zayo.com.,
CAIDA-GEOLOC -> Chicago, IL, US)
7 62.115.118.247 54.597 ms [x] (las-b22-link.ip.twelve99.net., CAIDA-
GEOLOC -> Los Angeles, CA, US)
8 62.115.11.129 55.979 ms
9 *
10 *
11 *
12 *
13 *
traceroute from 140.192.218.138 (Ark probe hosted in Chicago, IL, US at
Depaul University-AS20120) to 47.31.143.217 (MAXMIXD: Delhi, IN)
1 140.192.218.129 2.277 ms
2 140.192.9.124 0.449 ms
3 64.124.44.158 0.576 ms
4 *
5 *
6 64.125.15.65 1.814 ms [x] (zayo.telia.ter1.ord7.us.zip.zayo.com.,
CAIDA-GEOLOC -> Chicago, IL, US)
7 62.115.114.41 210.056 ms [x] (snge-b5-link.ip.twelve99.net.,)
8 62.115.177.11 200.840 ms
9 103.198.140.16 233.636 ms
10 103.198.140.16 232.871 ms
11 103.198.140.171 232.648 ms
12 *
13 *
14 *
15 *
16 *
________________________________ From: Lukas Tribus <lukas@ltri.eu> Sent: Monday, January 17, 2022 1:52 PM To: PAUL R BARFORD <pb@cs.wisc.edu> Cc: Nick Hilliard <nick@foobar.org>; nanog@nanog.org
<nanog@nanog.org>; Esteban Carisimo <esteban.carisimo@northwestern.edu>; Fabian E. Bustamante <fabianb@cs.northwestern.edu>
Subject: Re: Long hops on international paths
On Mon, 17 Jan 2022 at 20:00, PAUL R BARFORD <pb@cs.wisc.edu> wrote:
What we're curious about is why we're seeing a concentration of hops at a small number of routers that appear on international paths.
I suggest you share a few actual examples (IP addresses, traceroutes).
I don't think discussing your conclusion based on data we don't have makes sense.
Lukas
-- ++ytti