{HEAD ~ Proxy server} 105 may aggregate and store {TAIL ~ performance data} provided by control units 150 and 165, respectively 
{ HEAD ~ Proxy server } 105 may aggregate and store { TAIL ~ performance data } provided by control units 150 and 165 , respectively
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH