[39507] in North American Network Operators' Group
RE: DDoS attacks
daemon@ATHENA.MIT.EDU (Brad)
Thu Jul 12 13:55:31 2001
Date: Thu, 12 Jul 2001 11:54:40 -0600 (MDT)
From: Brad <brad@americanisp.net>
To: David Harmelin <david.harmelin@dante.org.uk>
Cc: Roeland Meyer <rmeyer@mhsc.com>, "'up@3.am'" <up@3.am>,
<nanog@merit.edu>
In-Reply-To: <4.2.2.20010712170411.044bae10@alpha.dante.org.uk>
Message-ID: <Pine.LNX.4.33.0107121152470.19601-100000@sh01>
MIME-Version: 1.0
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Errors-To: owner-nanog-outgoing@merit.edu
On Thu, 12 Jul 2001, David Harmelin wrote:
> At 08:45 AM 7/12/01 -0700, Roeland Meyer wrote:
>
> >This is the main point, a script-kiddie hunt, with prosecution, is the ONLY
> >real deterrent. Throw some of them in hotel greybar and remove them from
> >computing, for life, and we may see some of this turn around.
> >
> >If a lady wears skimpy clothing, does she deserve to get raped? Obviously,
> >not. If a computer has skimpy protection, does it deserve to be turned into
> >a zombie? Simply because you forget to lock your car one night (whilst in
> >your driveway), do you deserve to have it stolen? If you leave a $100 on
> >your kitchen table, in your unlocked house, whilst you are working in your
> >garage, do I have the right to sneak in the back door and take it while
> >avoiding prosecution, on the grounds that you were careless? WRT EFFnet,
> >does a prostitute deserve to be raped?
>
>
>
> By the way, for those who care, there are relatively easy ways to fight DoS attacks:
> * use netflow and a bunch of scripts to detect them automatically
> * use BGP to block them on all your border routers instantly, based on destination
> * use BGP and Unicast RPF to block them on all your border routers instantly, based on source, if you really need to
>
> With a combination of all that, you can automatically block any major attack at your border.
Sorry- but after doing all of that, DDoS attacks still
saturate even the largest circuits- thus denying the
service.
> Is it scalable? Yes.
Until the CPU overhead from netflow knocks out the
router(s) from a mass-attack.
> What about false alarms? We have implemented the detection bit.
> With a bit of tuning, we get 0.1% of false alarms and yet catch an average of 15 attacks per day, above 500 pkts/s (up to 10000s pkts/s).
> I wouldnt be surprised if Tier1 networks would catch much more attacks than that, with the same tool.
>
>
> My point: block automatically 99% of the DoS attacks at the top 10 transit providers level, and we may see DoS attacks be a thing of the past.
> "Kiddies only do it because they can".
>
> DH.
>
> ___________________________________________________________________
> * * David Harmelin Network Engineer
> * * DANCERT Representative
> * Francis House
> * 112 Hills Road Tel +44 1223 302992
> * Cambridge CB2 1PQ Fax +44 1223 303005
> D A N T E United Kingdom WWW http://www.dante.net
> ____________________________________________________________________
>
>
---
Brad Baker
Director: Network Operations
American ISP
brad@americanisp.net
+1 303 984 5700 x12
http://www.americanisp.net/
Fortune--
I will always love the false image I had of you.
