nanog mailing list archives
Re: Ownership of Routers on Both Ends of Transnational Links
From: Ross Tajvar <ross () tajvar io>
Date: Tue, 16 Apr 2019 16:50:11 -0400
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.lists () gmail com> wrote:
On Tue, Apr 16, 2019 at 10:59 AM James Jun <james.jun () 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 asNx10G or 100G. When yourIP transit provider assigns the /30, your router looks like it belongsto your upstream, commonmistake 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 onhttps://www.nanog.org/meetings/nanog47/presentations/Sunday/RAS_Traceroute_N47_Sun.pdfJames
Current thread:
- Ownership of Routers on Both Ends of Transnational Links Pengxiong Zhu (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Ross Tajvar (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links James Jun (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Christopher Morrow (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Ross Tajvar (Apr 16)
- Message not available
- Re: Ownership of Routers on Both Ends of Transnational Links Christopher Morrow (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Pengxiong Zhu (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links James Jun (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Pengxiong Zhu (Apr 16)
- Re: Ownership of Routers on Both Ends of Transnational Links Ross Tajvar (Apr 16)