Thank you so much for your insightful replies. We are asking the right people!
I checked the rest of them, they all seem to be /30 or /31s. 62.115.33.227 jax-b1-link.telia.net 62.115.33.228 telconet-ic-337544-jax-b1.c.telia.net 62.115.33.229 las-bb1-link.telia.net * 62.115.33.230 chinaunicom-ic-302366-las-bb1.c.telia.net 213.248.73.185 adm-b4-link.telia.net 213.248.73.186 riot-ic-303251-adm-b4.c.telia.net 213.248.73.187 213.248.73.188 213.248.73.189 sjo-b21-link.telia.net <http://sjo-b21-link.telia.net> * 213.248.73.190 chinaunicom-ic-127288-sjo-b21.c.telia.net. 152.179.103.250 0.xe-1-2-1.GW7.LAX1.ALTER.NET 152.179.103.250 chinaunicom-gw.customer.alter.net 152.179.103.251 152.179.103.252 152.179.103.253 0.xe-1-0-0.gw2.lax1.alter.net * 152.179.103.254 chinaunicom-gw.customer.alter.net. 63.243.205.89 ix-xe-0-3-3-0.tcore1.sqn-san-jose.as6453.net <http://ix-xe-0-3-3-0.tcore1.sqn-san-jose.as6453.net> * 63.243.205.90 63.243.205.91 63.243.205.92 63.243.205.93 ix-xe-8-2-5-0.tcore1.sqn-san-jose.as6453.net 66.110.59.117 ix-xe-2-1-3-0-0.tcore1.lvw-los-angeles.as6453.net * 66.110.59.118 66.110.59.119 66.110.59.120 66.110.59.121 ix-ae-2-611.tcore1.lvw-los-angeles.as6453.net How about the two IPs(63.243.205.90, 66.110.59.118) that don't have a reserve DNS name? Since they don't have any PTR records. Best, Pengxiong Zhu Department of Computer Science and Engineering University of California, Riverside On Tue, Apr 16, 2019 at 1:50 PM Ross Tajvar <r...@tajvar.io> wrote: > I think it's clear that the IPs belong to Telia, but I understood James's > point to be that the router using the IP in question may belong to China > Unicom. (I agree with that, I was not thinking clearly this morning.) As > this is an interconnect link, one side must belong to Telia and the other > to China Unicom. The question, then, is which side are we looking at? Well, > first I want to know how big the subnet is. I assume either /30 or /31. So, > I do a reverse DNS lookup on all the IPs in the surrounding /30 block: > 62.115.170.56 - sjo-b21-link.telia.net > 62.115.170.57 - chinaunicom-ic-341501-sjo-b21.c.telia.net > 62.115.170.58 - las-b24-link.telia.net > 62.115.170.59 - chinaunicom-ic-341499-las-b24.c.telia.net > That looks like two /31s. Only one IP in each has the name of China Unicom > in it, so that one is probably in use by China Unicom, and the other is > probably in use by Telia. > > On Tue, Apr 16, 2019, 3:50 PM Christopher Morrow <morrowc.li...@gmail.com> > wrote: > >> On Tue, Apr 16, 2019 at 10:59 AM James Jun <james....@towardex.com> >> wrote: >> >> > More likely, thease routers are China Unicom's routers in their US POP, >> not managed by VZ/Telia. >> > The /30s in this case are unmanaged IP transit hand-offs, coming in as >> Nx10G or 100G. When your >> > IP transit provider assigns the /30, your router looks like it belongs >> to your upstream, common >> > mistake when interpreting traceroutes[1]. >> > >> >> $ nslookup 62.115.170.56 >> 56.170.115.62.in-addr.arpa name = sjo-b21-link.telia.net. >> >> if you model (as james says) each interconnect as a /30 or /31 ... >> look for the adjacent ip and see the PTR for that ip. >> (the above is your first link example's peer ip) >> >> > [1]: see Page 22 on >> https://www.nanog.org/meetings/nanog47/presentations/Sunday/RAS_Traceroute_N47_Sun.pdf >> > >> > James >> >