Machine manager 610 understands the physical topology of the networks and keeps track of {HEAD ~ the location} of {TAIL ~ the physical machines} and virtual machines which are members within each of the networks 
of
Machine manager 610 understands the physical topology of the networks and keeps track of { HEAD ~ the location } of { TAIL ~ the physical machines } and virtual machines which are members within each of the networks
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH