The method 5, wherein said determining whether {HEAD ~ the given received pair} of {TAIL ~ connected nodes} is allowable further comprises: 
of
The method 5 , wherein said determining whether { HEAD ~ the given received pair } of { TAIL ~ connected nodes } is allowable further comprises :
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH