- SELF-UPDATABLE ENCRYPTION METHOD OF CIPHERTEXT

摘要

Disclosed is a self-updatable encryption method of ciphertext. The encryption method includes: an initializing step in a server transmits a double-line function (p, G, G_T, e) and a generation source (g) to a transmitting terminal; a setting step in which the transmitting terminal generates a master key (MK) and a public parameter (PP); a key generation step in which the transmitting terminal generates a private key (SK_T) for the time (T); an encryption step in which the transmitting terminal generates a session key (EK) and a cryptogram header; an update step in which the server generates an updated cryptogram header (CH_T); a verification step in which a receiving terminal verifies the validity of the cryptogram header; and a decoding step in which the receiving terminal generates the session key (EK).