Method and system for id-based encryption and decryption

An identifier (ID)-based decryption method, comprising:

• storing, at a receiving terminal, a receiving-side private key corresponding to a receiving-side ID issued by a key issuing server;
• generating, at the receiving terminal, a session key using a transmitting-side ID, the receiving-side ID, and the receiving-side private key;
• extracting, at the receiving terminal, a secret key from at least a part of the session key;
• and
• decrypting, at the receiving terminal, an encrypted message using a previously set decryption algorithm and the secret key.

An apparatus, comprising:

• at least one hardware processor;
• a memory accessible by the at least one hardware processor;
• and
• at least one program stored in the memory;
• wherein the at least one program is configured to be executed by the at least one hardware processor, and includes commands enabling the at least one hardware processor to:
• store a transmitting-side private key corresponding to a transmitting-side identifier (ID) issued by a key issuing server;
• generate a session key using the transmitting-side ID, a receiving-side ID, and the transmitting-side private key;
• extract a secret key from at least a part of the session key;
• and
• encrypt a message using a previously set encryption algorithm and the secret key.

An apparatus, comprising:

• at least one hardware processor;
• a memory accessible by the at least one hardware processor;
• and
• at least one program stored in the memory;
• wherein the at least one program is configured to be executed by the at least one hardware processor, and includes commands enabling the at least one hardware processor to:
• store a receiving-side private key corresponding to a receiving-side identifier (ID) issued by a key issuing server;
• generate a session key using a transmitting-side ID, the receiving-side ID, and the receiving-side private key;
• extract a secret key from at least a part of the session key;
• and
• decrypt an encrypted message using a previously set decryption algorithm and the secret key.