On Sun, Mar 17, 2013 at 11:33 AM, Arturo Servin <arturo.servin@gmail.com> wrote:
Yes, BCP38 is the solution.
Now, how widely is deployed?
Someone said in the IEPG session during the IETF86 that 80% of the service providers had done it?
right... sure.
This raises two questions for me. One, is it really 80%, how to measure it?
csail had a project for a while... spoofer project? <http://spoofer.csail.mit.edu/> I think the last I looked they reported ONLY 35% or so coverage of proper filtering. Looking at: <http://spoofer.csail.mit.edu/summary.php> though they report 86% non-spoofable, that seems very high to me.
Second, if it were 80%, how come the 20% makes so much trouble and how to encourage it to deploy BCP38?
some of the 20% seems to be very highspeed connected end hosts and at a 70:1 amplification ratio you don't need much bandwidth to fill a 1g pipe, eh? -chris
(well, actually 4 questions :)
Regards, as
On 3/16/13 7:24 PM, Jon Lewis wrote:
On Sat, 16 Mar 2013, Robert Joosten wrote:
Hi,
Can anyone provide insight into how to defeat DNS amplification attacks? Restrict resolvers to your customer networks.
And deploy RPF
uRPF / BCP38 is really the only solution. Even if we did close all the open recursion DNS servers (which is a good idea), the attackers would just shift to another protocol/service that provides amplification of traffic and can be aimed via spoofed source address packets. Going after DNS is playing whack-a-mole. DNS is the hip one right now. It's not the only one available.