UDP port 80 DDoS attack

Mon Feb 6 03:30:20 UTC 2012

2012/2/5 Steve Bertrand <steve.bertrand at gmail.com>

> On 2012.02.05 20:37, Keegan Holley wrote:
>
>> 2012/2/5 Dobbins, Roland<rdobbins at arbor.net>
>>
>
>  S/RTBH - as opposed to D/RTBH - doesn't kill the patient.  Again, suggest
>>> you read the preso.
>>>
>>>
>> Source RTBH often falls victim to rapidly changing or spoofed source IP"s.
>> It also isn't as widely supported as it should be. I never said DDOS was
>> hopeless, there just aren't a wealth of defenses against it.
>>
>
> This is so very easily automated. Even if you don't actually want to
> trigger the routes automatically, finding the sources you want to blackhole
> is as simple as a monitor port, tcpdump and some basic Perl.
>

This is still vulnerable to spoofing which could cause you to filter
legitimate traffic and make the problem worse.  Not saying that S/RTBH is a
bad idea.  RTBH is effective and a great idea just not very elegant.

>
> ...and as far as this not having been deployed in many ISPs (per your next
> message)... their mitigation strategies should be asked up front, and if
> they don't have any (or don't know what you speak of), find a new ISP.
>

You sometimes have to weigh the pro's and cons.  You can't always pick the
guys with the coolest knobs.