Bare metal hypervisor
Runs on hardware
Hosted hypervisor
runs on top of os
What was the vision of VM370
each user has their own os
Why is virtualization popular now
Companies want to provide services (utility)
Trap and execute
The guest OS issues privileged instruction this is trapped by the hypervisor
How are instructions trap do not trap handled
Binary editing. The vm edits those op codes to a set of instructions that will cause a trap
What is para virtualization
the vm provides calls that the guest os kernel can take advantage of (xen)