Patent ID: 8200970

Claim:
A method for preventing a replay attack, comprising the steps of: mutually exchanging a prime number between a main node and one or more children nodes; generating, by the main node, a Prime Sequence Code Matrix (PSCM) corresponding to the prime number; notifying, by the main node, the one or more children nodes of sequence orders corresponding to the one or more children nodes; selecting, by the main node, an arbitrary value of a Prime Sequence Code-1 (PSC1) among a series of values corresponding to an arbitrary node in the PSCM; computing, by the arbitrary node, a Prime Sequence Code-2 (PSC2) subsequent to receiving the PSC1 using a sequence order received from the main node and the prime number, and transmitting PSC2 to the main node; and comparing, by the main node, the received PSC2 with the PSCM.