[110065] in North American Network Operators' Group
RE: What is the most standard subnet length on internet
daemon@ATHENA.MIT.EDU (Tomas L. Byrnes)
Mon Dec 22 21:40:56 2008
Date: Mon, 22 Dec 2008 18:40:19 -0800
In-Reply-To: <41036FF1-4200-4D16-B69D-1D3A91DDFCC1@daork.net>
From: "Tomas L. Byrnes" <tomb@byrneit.net>
To: "Nathan Ward" <nanog@daork.net>,
"nanog list" <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
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
>
>
>
>
