nanog mailing list archives

Re: Effective ways to deal with DDoS attacks?


From: "Christopher L. Morrow" <chris () UU NET>
Date: Thu, 2 May 2002 05:10:54 +0000 (GMT)



On Wed, 1 May 2002, Pete Kruckenberg wrote:


On Wed, 1 May 2002 measl () mfn org wrote:

and then again, there has been much discussion on simple
DoS attacks, where the term DDoS is erroneously used...
I am very much not trying to imply that this is the case
here, but it's important that the two be thoroughly
distinguished from each other - they are totally
different things to deal with.

Sorry, I should have been more clear.

My issue (currently)  is not being the target of the DDoS
attack, but being a (unwilling) participant. People outside
our network are launching DDoS attacks (distributed SYN
floods) against destinations outside our network, using
about 8,000 Web server hosts on our network as reflectors.

Funny, you say 'secured' here...


These are not zombies. They are secured, uncompromised Web
servers. The attack spoofs the target address as the source,
and one of our machines as a destination, port 80. Getting
everyone to implement defenses (SYN cookies) on their Web
servers is nearly impossible (most don't even have a
defense--printers and routers with Web interfaces).


and here you say: "printers and routers" Since when did they need to be
accessible off campus? Additionally, why does a router need a web
interface?? Printers are on the cusp, but they certainly don't need to be
accesible from out of your LAN.


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