RE: What is the most standard subnet length on internet

["Tomas L. Byrnes" <tomb () byrneit net>]

BGP Hijacking.

Fully peered network A accepts routes from its peers based on prefix
allocation to AS maps.

Network B, which is either pathological (criminal, or bent on
censorship) or lacking clue, propagates /24 subnet of Network C's CIDR
(Pakistan/YouTube anyone).

If network A accepts Network B's announcement, then connectivity from
network A to the /24 announced by Network B (which isn't really
connected to network B) is either lost, or worse, hijacked.


> -----Original Message-----
> From: Nathan Ward [mailto:nanog () daork net]
> Sent: Monday, December 22, 2008 5:45 PM
> To: nanog list
> Subject: Re: What is the most standard subnet length on internet
>
> On 23/12/2008, at 2:39 PM, Joe Provo wrote:
>
> > On Tue, Dec 23, 2008 at 02:34:39PM +1300, Nathan Ward wrote:
> > [snip]
> > > Let me rephrase; Are there people who are filtering /24s received
> > > from
> > > eBGP peers who do not have a default route?
> >
> > of course.
>
>
> Curiously, it was really meant as a rhetorical question where the
> answer was "no".
>
> Why are people doing this? Are they lacking clue, or, is there some
> reasonable purpose?
>
> --
> Nathan Ward