ietf-dkim
[Top] [All Lists]

Re: [ietf-dkim] 1193 considered harmful

2006-03-23 10:30:26

On Mar 23, 2006, at 10:23 AM, Arvel Hathcock wrote:

> 3) +   can hash a body once for redistribution; a fairly marginal
>        feature that might help mass mailers, but Moore's law is just
>        as likely to help, um, more.

For mailing lists which sign their outbound traffic surely this benefit is more than marginal; especially for large lists? I don't have as much knowledge here as Mike and I'm no crypto expert (thank God for OpenSSL BTW) but isn't the hashing part what takes the longest (sorry if I'm wrong on that).

Here is an interesting link on performance.

http://www.eskimo.com/~weidai/benchmarks.html

The MB/S rating of the hashing function is therefore dependent upon the size of the message. The RSA overhead is dependent upon the key size.

The advantage found by the hash parameter from the verification perspective is found when considering the related overhead related to weeding through a series of possibly "broken" signatures (largely related to more expensive DNS transactions) and various added signatures when this becomes more common place.

-Doug



_______________________________________________
NOTE WELL: This list operates according to http://mipassoc.org/dkim/ietf-list-rules.html