Re: Authenticated cipher modes

[Ben Harris <bjh21%bjh21.me.uk@localhost>]

In article <4267CC68.5030909%streamsec.se@localhost> you write:
>Ben Harris wrote:
>
>> 2: Feed a counter through a one-way function (either a block cipher or a
>>    hash) to generate the nonce.  This is more expensive (at least if you
>>    use a hash), but saves on network traffic and means that the sequence
>>    number is implicit in the nonce so that it need not be processed by
>>    Helix (though it may as well be, since doing so is cheap).
>
>The obvious solution would be to use a separately keyed instance of 
>Helix as a continuous PRNG. The PRNG seed (i.e. the second Helix key and 
>nonce) could be the initial IV from the NEWKEYS.

Ah yes, of course.  Why didn't I think of that?

-- 
Ben Harris