Practical ID-based encryption for wireless sensor network

In this paper, we propose a new practical identity-based encryption scheme which is suitable for wireless sensor network (WSN). We call it Receiver-Bounded Online/Offline Identity-based Encryption (RB-OOIBE). It splits the encryption process into two parts - the offline and the online part. In the offline part, all heavy computations are done without the knowledge of the receiver s identity and the plaintext message. In the online stage, only light computations such as modular operation and symmetric key encryption are required, together with the receiver s identity and the plaintext message. Moreover, since each offline ciphertext can be re-used for the same receiver, the number of offline ciphertexts the encrypter holds only confines the number of receivers instead of the number of messages to be encrypted. In this way, a sensor node (with limited computation power and limited storage) in WSN can send encrypted data easily: A few offline ciphertexts can be computed in the manufacturing stage while the online part is light enough for the sensor to process.