No detailed explanation is needed for these posters. Very useful way to study or explain a technology. Download them from here.
Sometimes live migration job can take longer than 30 minutes depending on the virtual machine you migrate and the network. If the job passes 30 min limit that job is terminated. Of course if you have such long jobs you can actually increase that time out value. To find out how look here.
A nice tip from SCVMM team on how to configure this setting in SCVMM 2012 SP1.