A New Efficient Certificateless Multi-Receiver Public Key Encryption Scheme

Multi-receiver public key encryption is important in insecurity and open network environment and has been applied in many scenarios such as first pay television system, streaming media services and so on. To avoid costly management of certificate and settle the matter of key escrow, we combine multi-receiver public key encryption with certificateless cryptography, and then present the notion, security model as well as a concrete scheme for certificateless multi-receiver encryption. Our new ideal scheme is efficient and only needs one (or none if precomputation has been considered) pairing computation in the step of encryption. Meanwhile, we prove the IND-CCA security of our scheme under the intractability of CDHI and Gap-BDH problem. The efficient scheme is able to be generally applied in a variety of scenarios especially in broadcast communication.