In operation, network access tier devices collect {HEAD ~ security information} about {TAIL ~ each connected end user device} serviced by the access device 
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In operation , network access tier devices collect { HEAD ~ security information } about { TAIL ~ each connected end user device } serviced by the access device
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH