Blair Sadewitz wrote:

> Aside from power consumption, there is also the issue of physical
> volume.  Putting another machine in a rack just to do crypto--even if
> you found it on the street--could very well end up costing a lot more
> in colocation fees than a crpyto card would.  This is especially true
> in parts of the world with government-owned PTTs, etc.  All things
> considered, if you have a few crypto cards, the price differential
> could scale geometrically.
>
> This is saying nothing about a PC having many more points of failure
> than a PCI card.  I doubt that any x86-based machine which is reliable
> as a crypto card would save anyone much money.
>
> --Blair
>
The main reason is the cards are meant to keep the private key on the 
card, (like an HSM)  (and secure)
They are (really not) used to speed up RSA's (unless you count the not 
used CPU time for this)

mfc

thilo