"general badness" AS-based reputation system

Gadi Evron ge at linuxbox.org
Mon Sep 26 13:52:04 UTC 2011

On 9/26/11 2:31 AM, Jimmy Hess wrote:
> Sorry... what makes  you think the problem with use of a
> AS-reputation systems is
> social and not technical?
> IP packets are not stamped with the numbers of any of the AS they
> transitted to reach your network.
> The IP protocol simply does not expose AS number information,
> therefore,  for filtering purposes,
> you don't actually have the information....

Filtering is dangerous, especially when done with ASNs. There are many 
technical challenges and many levels of filtering, all are technical 
issues and policy decisions based on how bad it's needed. Let's not 
forget how dangerous it is to block a network just to find out that your 
customers no longer get service, that is a much bigger issue that 
figuring our what is out technically, IMO.

I am in agreement with you -- which is why I focus on the cultural aspect.


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