Re: [Codel] hardware multiqueue in fq_codel?

[Eric Dumazet <eric.dumazet@gmail.com>]

On Fri, 2013-07-12 at 12:37 -0400, Dave Taht wrote:

> This is not strictly true, as the hash is permuted by a secret random
> number, any level of dumb attack as an attempt to fill all available queues
> will need to vastly exceed the packet limit rather than the number of queues,
> thus yielding the same behavior as a normal attack against pfifo_fast, and
> in the general case an attack that would overwhelm pfifo_fast won't be
> anywhere near as damaging against fq_codel.

I can give you a program doing a flood on random destination IP, and I
will tell you it will fill your fq_codel buckets. All of them. secret
random number wont help at all.

Or just think of SYN flood attack.