> > Basicaly, is the PCI bus a bottle neck for crypto card or is it the > > chip on the card? > > No. > > The scatter gather interface is the bottleneck. This is normally > setup a bit like an ethernet or scsi chipset's "outstanding operations > list", but you need to be able to cut virtual address ranges into > blocks of physical addreses and such. This makes the interface more > complicated. But the real complexity is in the software side if you > make an interface that is not sufficiently flexible.
Let me explain a bit further. Bandwidth is not the problem. LATENCY IS. If the hand-off-and-hand-back from driver-to-the-card-and-back-to-the-driver sucks, the entire thing will suck. Think that through.
