On-going Internet Emergency and Domain Names

Mikael Abrahamsson swmike at swm.pp.se
Sat Mar 31 10:57:26 UTC 2007

On Sat, 31 Mar 2007, Gadi Evron wrote:

> In this case, we speak of a problem with DNS, not sendmail, and not bind.

The argument can be made that you're trying to solve a windows-problem by 
implementing blocking in DNS.

Next step would be to ask all access providers to block outgoing UDP/53 so 
people can't use open resolvers or machines set up to act as resolvers for 
certain DNS information that the botnets need, as per the same analysis 
that blocking TCP/25 stops spam.

So what you're trying to do is a pure stop-gap measure that won't scale in 
the long run. Fix the real problem instead of trying to bandaid the 

Mikael Abrahamsson    email: swmike at swm.pp.se

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