BGP hijack from 23724 -> 4134 China?

Suresh Ramasubramanian ops.lists at
Fri Apr 9 01:28:02 CDT 2010

It depends.  Preventing packet flow from a rather more carefully
selected list of prefixes may actually make sense.

These for example -

Filtering prefixes that your customers may actually exchange valid
email / traffic with, and that are not 100% bad is not the best way to

Block specific prefixes from China, the USA, Eastern Europe, wherever
- that are a specific threat to your network .. great.   Even better
if you are able to manage that blocking and avoid turning your router
ACLs into a sort of Hotel California for prefixes.

On Fri, Apr 9, 2010 at 11:52 AM, Daniel Karrenberg
<daniel.karrenberg at> wrote:
> **** Selectively preventing packet flow is *not* a security measure.
> **** Selectively preventing packet flow leads to unexpected and hard to diagnose breakage.
> **** Many independent actors selectively preventing packet flow will eventually
>     partition the Internet sufficiently to break it beyond recognition.

Suresh Ramasubramanian (ops.lists at

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