Additionally, {HEAD ~ one microprocessor} could be shared to handle {TAIL ~ multiple DID trunk} or E&M tie lines 
Additionally , { HEAD ~ one microprocessor } could be shared to handle { TAIL ~ multiple DID trunk } or E&M tie lines
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH