[ietf-dkim] Comments on -overview document?

[Steve Atkins]

On Jul 10, 2006, at 1:26 PM, Michael Thomas wrote:

> Eliot Lear wrote:
>
>> Bill,
>>
>> I think what Dave could say is that in I/O intensive environments  
>> DKIM
>> will have a negligible impact because minimal disk I/O is  
>> required.  If
>> your environment is not I/O bound then of course DKIM will have a
>> marginal impact.  If you're using your CPUs efficiently already,  
>> good on
>> you!
>>
> The point that Bill brings up, however, is a good one and I suspect  
> that he's
> entirely right if one considers the _inbound_ which is very likely  
> to be very
> CPU bound with anti-spam/virus/malware/etc. Still in that case,  
> it's not clear
> that the DKIM overhead is likely to be very significant as the main  
> cost for
> smallish messages may not even be bound to the RSA and/or SHA overhead
> (seeing how RSA verifies are so much cheaper than signing).

Arguably, DKIM allows easy whitelisting of high-volume senders, allowing
the recipient to skip content-based spam filtering for that mail. That's
likely to be a significant fraction of inbound mail, so may reduce  
the CPU
overhead overall.

> In any case, I think he's right that in order to give advise we'd  
> do well to
> actually state the test cases for which somebody could do their own
> experimenting.

Definitely.

Cheers,
   Steve