RE: key change for TCP-MD5

[Randy Bush <randy () psg com>]

> > The added cost for CPU-bound systems is that they have to try
> > (potentially) multiple keys before getting the **right** key
> > but in real life this can be easily mitigated by having a rating
> > system on the key based on the frequency of success.
>
> This mitigates the effect of authenticating valid packets. However,
> this does not appear to help at all in terms of minimizing the DOS
> effect of an intentional DoS attack that uses authenticated packets
> (with the processing time required to check the keys the intended
> damage of the attack).

gstm