The policy adapters transform the single unified method call into formats acceptable by {HEAD ~ each associated policy servers} and place the transformed requests to {TAIL ~ the associated servers} 
The policy adapters transform the single unified method call into formats acceptable by { HEAD ~ each associated policy servers } and place the transformed requests to { TAIL ~ the associated servers }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL