| 摘要 |
The present invention relates to a system for maintaining the security of a message by preventing the message from being forged by an external attack against the message encrypted through the ID based signcryption. The disclosed system for maintaining the security of the message includes: an encryption unit for applying a hash function to a value, which may be obtained only by a transmitter, among values used to encrypt a message (m) through an ID based signcryption and performing the encryption of the message (m); and a decryption unit for decrypting the message (m). The encryption unit performs the encryption with respect to values that may be acquired only by the decryption unit. When a message is encrypted through the ID based signcryption scheme according to the present invention, the hash function is applied to a value, which may be obtained only by the transmitter, among values for encryption in order to perform the encryption for the message, and values, which may be acquired only by a receiver in a decryption process or a verification process, are subject to the encryption. Accordingly, the safety of the message can be ensured from an external attack. [Reference numerals] (11) Set-up unit; (12) Secret key generation part; (13) Encoding unit; (14) Decoding unit; (15) Verification unit |
