BCP 38 coverage if top x providers ...

Fri Mar 24 15:07:50 UTC 2017

* Jared Mauch:

>> On Nov 19, 2016, at 9:13 PM, Frank Bulk <frnkblk at iname.com> wrote:
>> 
>> My google fu is failing me, but I believe there was a NANOG posting a year
>> or two ago that mentioned that if the top x providers would
>> implement BCP 38
>> then y% of the traffic (or Internet) would be de-spoofed.  The point was
>> that we don't even need everyone to implement BCP 38, but if the largest
>> (transit?) providers did it, then UDP reflection attacks could be
>> minimized.
>> 
>> If someone can recall the key words in that posting and dig it up, that
>> would be much appreciated.

> A double lookup of the packet is twice as expensive and perhaps
> impractical in some (or many) cases.

Do you actually have to filter all packets?

Or could you just sample a subset and police the offenders, on the
assumption that if you don't implement an anti-spoofing policy, you
end up with near-constant leakage?