Re: Newbie Needs Help: someone is announcing less-specific IPv6 (BGP) route on top of me

[Tom Beecher via NANOG <nanog () lists nanog org>]

> A route to 2400::/12 is effectively a route to North America - well, part
> of it, because ARIN has more than one prefix.


2400::/12 is APNNIC, not ARIN.

https://www.iana.org/assignments/ipv6-unicast-address-assignments/ipv6-unicast-address-assignments.xhtml


On Sat, Aug 30, 2025 at 12:54 PM nanog--- via NANOG <nanog () lists nanog org>
wrote:

> 2400::/12 is larger than any prefix allocated to a network. In fact it's a
> prefix allocated to ARIN, which sub-allocates prefixes to various North
> American networks.
>
> A route to 2400::/12 is effectively a route to North America - well, part
> of it, because ARIN has more than one prefix.
>
> Network operators can announce whatever they want to their customers. It's
> not uncommon for some customers to get summarized routes. Some ISP far away
> from America could be telling its customers "yes, I know how to get to
> North America".
>
> This radar tool seems to be showing what ISPs tell it, without filtering
> such ISP-specific routes. You can see other "invalid" routes such as /128
> routes in the same tool. Such routes won't propagate across the whole
> internet, by convention, but there's no rule that a single ISP can't use
> them.
>
>
>
> On 30 August 2025 08:58:21 CEST, Pirawat WATANAPONGSE via NANOG <
> nanog () lists nanog org> wrote:
> > Dear Gurus,
> >
> >
> > Radar tool by Qrator [Reference: https://radar.qrator.net ] claims that
> > Zenlayer Inc. [AS4229] is “umbrella-ing” me by announcing ‘2400::/12’ on
> > top of my more-specific address block.
> > The tool classifies it as a type of hijacking.
> > [Disclaimer: apologies to Zenlayer if you didn’t do it; but that’s the
> > information I received]
> > My neighboring organization also has a more-specific block that falls
> under
> > The Umbrella too.
> >
> > However, other tools (https://stat.ripe.net ,
> https://irrexplorer.nlnog.net
> > , https://bgp.he.net , etc.) seem unable to see that particular
> > announcement.
> >
> > Questions:
> > 1. Is Qrator claim true? (because I have already tried but cannot verify)
> > 2. If so, should I be concerned?
> > Even though I already ROA-ed *and* IRR-ed my own block, but if “the other
> > end” doesn’t validate, it won’t do any good, correct?
> > (Oh, yeah, the other end also has to somehow “not see” my longer-prefix.
> > But that can happen as well, no?)
> > 3. In that case, what more do I must do?
> >
> > I would extremely appreciate someone helping me out on this matter.
> >
> >
> > Best Regards,
> >
> > Pirawat.
> > _______________________________________________
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