What is the most standard subnet length on internet

Tomas L. Byrnes tomb at byrneit.net
Tue Dec 23 02:40:19 UTC 2008


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 at 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
>
>
>
>





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