For example, {HEAD ~ a topology service} may be implemented within a virtual computing environment, which may in turn include {TAIL ~ virtual computing instances} 
For example , { HEAD ~ a topology service } may be implemented within a virtual computing environment , which may in turn include { TAIL ~ virtual computing instances }
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL