libvirt users - Jun 2013 - Migration between 2 hosts

Hi ,
   How does migration of VMs between 2 hosts work ? Say we want to migrate a VM
from host A - > B , does it create a process on B, copy all the data of the
process on A to B and then once done kill process on A. Is it how it happens ?

Can someone tell me how the copying of data between process on A and new process
on B is done ?

Regards,
Navin