ENCRYPTION AND DECRYPTION SCHEME BASED ON ELLIPTIC CURVE

摘要

PURPOSE: An encryption and decryption scheme based on an elliptic curve are provided to reduce a load of internal calculation by using 10 bits parameter instead of more than 160 bits. CONSTITUTION: In an encryption and decryption scheme based on an elliptic curve, an arbitrary coordinate G, P parameter on an elliptic curve is generated by substituting a predetermined 10 bits parameter(S10). Public keys of a tag and public keys of a reader are transmitted to the other communication device(S20). The same cryptographic key C1 and C2 are generated by multiplying random number with the received public keys(S30). Transmission data is encrypted by a second step by using a cryptographic key C1 and C2(S40). The encrypted data is transmitted to the other communication device processing an authentication process(S50). The transmitted data is encrypted(S60).