An integrated circuit for a Radio Frequency Identification reader configured to communicate with {HEAD ~ an RFID tag} that stores {TAIL ~ a first code}, determines a response to a challenge, and backscatters the first code responsive to receiving a first command, the integrated circuit configured to: 
stores
An integrated circuit for a Radio Frequency Identification reader configured to communicate with { HEAD ~ an RFID tag } that stores { TAIL ~ a first code } , determines a response to a challenge , and backscatters the first code responsive to receiving a first command , the integrated circuit configured to :
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH