On 09/03/2010 15:12, [email protected] wrote: > On Tue, 09 Mar 2010 15:27:02 +0100, Adrenalin said: >> I'm just wondering, even if it's under DDoS, isn't it as easy to block as to >> collect the list of IP that send too much data, and just block them on the >> upper level ISP ? > > You *do* realize that a *small* botnet these days is 75,000 machines, and > there's a estimated 140 million compromised zombie boxes out there? There's > very few boxes that can handle an inbound ACL of 75K entries sanely - usually > what ends up happening is the upstream drops all traffic *to* the target node > just so all the *other* boxes at the site still get some bandwidth. > > And "sending too much data" is hard to quantify - if you have enough bots, > you can thoroughly DDoS a site using far *less* bandwidth per host than a > normal user does. If the site was designed to handle 10,000 clients each > sending 5 packets per second for 10 seconds during a login at game start, > it will likely fall over if you throw 100,000 bots at it, each sending > 4 packets a second continuously... >
I've worked at huge online better company and they had network devices that worked to stop DDoS as we got hit quite a bit. I have to say they managed quite well, often we would only notice because we regularly checked the graphs over 24 hours periods. Other times the attacks had some successes but they worked well. Can't remember what they where called...think it was a company that ended up being bought by Cisco, though we did have cards in the 6500 routers to also help out with DDOS. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
