Fw: GLBX ICMP rate limiting (was RE: Tier-1 without their own backbone?)

Thu Aug 28 15:03:27 UTC 2003

On Thu, 28 Aug 2003, Gordon wrote:

>
>
> Of the DDOS attacks I have had to deal with in the past year I have seen
> none which were icmp based.
> As attacks evolve and transform are we really to believe that rate limiting
> icmp will have some value in the attacks of tomorrow?

The folks doing the attacking aren't 100% stupid... If their tcp flooder
fails they will attempt udp then icmp or some other serial list of
flooding tools. A large number of the 'bot' programs today have multiple
flooding tools on them, so attempt proto X, if !success then attempt proto
Y and so on :(

Rate-limiting ICMP is 'ok' if you, as the provider, think its worthwhile
and you, as the provider, want to deal with the headache phone calls...
It might not stop everything, but in reality nothing really can :( If
someone really wants your site/system/server off the network its as good
as gone.

-Chris