> > Peter wrote: > > > Still I am trying to understand encryption and decryption > > > load goes to general CP Incase if you don't have CPACF or > > > ICSF ?
> Phil Smith III wrote: > > Even with CPACF and ICSF, some/most of the encryption load > > is on the CPU. > > They aren't magic. CPACF is faster, but it's still > > fundamentally executing Z instructions in the millicode. Tony H wrote: > Really? Surely there is on-chip crypto hardware that the > millicode invokes to do much of the work? I can't imagine it's > just like the millicode implementation of the sort > instructions or something. You are correct. The CPACF is a physically separate chip that runs in lockstep with the CP that invokes it. So, it is does cost general CP but much less than implementing it in millicode. > But I think the OP deserves a simple answer: YES. If there's > no crypto hardware then ICSF will do it all using ordinary > zArch instructions. If there is no crypto hardware (no CPACF), ICSF won't start. > In the early days there was (is?) even an ability to plug your > own crypto provider software into the back end of ICSF, with > interface documentation "by request only". I've been in ICSF for over 25 years. I've never heard of this. Eric Rossman ICSF architect ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
