Re: Long hops on international paths

[Christopher Morrow <morrowc.lists () gmail com>]

Looking at your 1 repeat ORD example:

On Tue, Jan 18, 2022 at 12:17 AM PAUL R BARFORD <pb () cs wisc edu> wrote:

> 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)
 65.15.125.64.in-addr.arpa name = zayo.telia.ter1.ord7.us.zip.zayo.com.
64.15.125.64.in-addr.arpa name = ae51.zayo.ter1.ord7.us.zip.zayo.com.

it looks like the probes you selected (at least the depaul univ one(s)) are
finding the 'best path' to whatever destinations via depaul -> zayo ->
telia.
It looks like zayo/telia interconnect at that /31.
Based on:

https://www.teliacarrier.com/dam/jcr:fc260a69-98a2-47d3-8d30-ca7095318413/telia-carrier-map-america-nov-2021.png

i'd guess that:
 1) telia has an mpls core with no-decrement-ttl enabled
 2) the hidden hosp include NYC and possibly cleveland/wdc
 3) judging the path information purely on traceroute hops is error prone.