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Re: DDoS - CoD?


From: "Dobbins, Roland" <rdobbins () arbor net>
Date: Tue, 6 Sep 2011 08:00:45 +0000

On Sep 6, 2011, at 2:53 PM, BH wrote:

Has anyone seen similar traffic before? I

I've seen DDoS traffic on UDP/80 as far back as 2002 - the miscreants often don't know a lot about TCP/IP, and if 
something happens to work once, they incorporate it into their attack tool defaults and keep using it over and over.

In several recent high-profile DDoS attacks, UDP/80 traffic ended up causing state exhaustion on load-balancers, as the 
victim sites weren't following the BCP of enforcing network access policies via stateless ACLs in hardware-based 
routers/layer-3 switches, and the load-balancers kept trying to load-balance this traffic from multiple purported 
source IPs/source ports.

-----------------------------------------------------------------------
Roland Dobbins <rdobbins () arbor net> // <http://www.arbornetworks.com>

                The basis of optimism is sheer terror.

                          -- Oscar Wilde



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