Identity-based Multi-Recipient Public Key Encryption Scheme and Its Application in IoT

The Internet of Things (IoT) has become a research hotspot in recent years. With the increase of smart devices which are connected in IoT, the privacy of IoT has become an important problem. Multi-recipient public key encryption (MRPKE) system plays an important role in protecting the privacy of those smart devices in IoT. At present, the existing ID-MRPKE schemes can only achieve the security in the random oracle model. To enhance the security level, a new ID-MRPKE is constructed by using the programmable hash function from multilinear maps. The security of the novel scheme can be proven in the standard model, instead of the random oracle. Furthermore, based on the k-level Multilinear-maps Decisional Deffie-Hellman (MDDH) assumption, we prove that the proposed scheme has the indistinguishability under the selective multi-identity attack and chosen plaintext attack (IND-sMID-CPA).