I was joking, I meant that the operator provides an API for attackers, so they 
can accomplish their goal of taking the customer offline, without having to 
spoof or flood or whatever else.  Automatically installing ACLs in response to 
observed flows accomplishes almost the same thing.  As a concrete example, say 
a customer is running a game server that utilizes UDP port 12345.  An attacker 
sends a large flow to customer:12345 and your switches and routers all start 
filtering anything with destination customer:12345, for say 2 hours.  Then the 
attacker can just repeat in 2 hours and send only a few seconds worth of 
flooding each time.

On Feb 4, 2014, at 6:52 PM, William Herrin <b...@herrin.us> wrote:

> On Tue, Feb 4, 2014 at 1:45 PM, Laszlo Hanyecz <las...@heliacal.net> wrote:
>> Why not just provide a public API that lets users specify which
>> of your customers they want to null route?
> 
> They're spoofed packets. There's no way for anyone outside your AS to
> know which of your customers the packets came from. It's not
> particularly easy to trace inside your AS either.
> 
> Regards,
> Bill Herrin
> 
> 
> 
> -- 
> William D. Herrin ................ her...@dirtside.com  b...@herrin.us
> 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
> Falls Church, VA 22042-3004


Reply via email to