Method for maintaining the security of a message encrypted using Identity based Signcryption System thereof

摘要

The present invention relates to a system capable of preventing forgery and falsification of an encrypted message encrypted by an ID-based private encryption scheme, thereby maintaining the security of the message. In order to maintain safety, the disclosed system performs encryption of the m by applying a hash function on a value that only the sender can have among the values used for encrypting the message (m) by the ID-based private encryption And a decryption unit for decrypting the m, and the encryption unit includes a value that can be acquired only by the decryption unit in encryption. In the case of encrypting a message according to the ID-based encryption technique according to the present invention, a message is encrypted by applying a hash function to a value that only a sender can have among values used for encryption, and in a decryption or verification process Since the value that can be obtained only by the receiver is included in the encryption process, the message can be secured from the external attack.