Re: [IPsec] Proposed method to achieve quantum resistant IKEv2

[Paul Wouters <[e-mail]>]

On Fri, 29 Sep 2017, Valery Smyslov wrote:

>>    Adding IKE-level fragmentation to the process adds an additional place
>>    that DDoS attacks can hit.
>
> We have DDoS protection mechanisms. I think it's possible to define 
> IKE_SA_INIT fragmentation so that these mechanisms be still able to work.

That would be tricky. Either a new exchange or an untrusted stream of
fragments. Either way, a lot of complexity for a rather moving target
goal that we don't understand yet. I'd personally rather wait until we
know a bit more about the direction that quantum safe protocols are
really going to.

>>    So, one would have to have some mechanism to know what would get through,
>>    and if to switch to TCP, etc. before even trying.
>
> TCP has a lot of shortcomings. It's a last resort.

Agreed. It's the emergency backup parachute, not the real parachute.

People are suggesting a lot of complicated bells and whistles. I wish we
would not compete with TLS on which can be more complicated :P

Paul