A novel identity-based multi-signcryption scheme

Signcryption is a novel cryptographic primitive that simultaneously provides the authentication and encryption in a single logic step. In this work, by combining multi-signature with ID-based signcryption scheme, we build security model of multi-signcryption and have proposed an ID-based multi-signcryption scheme based on the bilinear pairings to adapt to multi-user setting. Then we prove that our proposed scheme was secure and satisfies the confidentiality and unforgeability. And the fixed verification computational cost is needed in our proposed signcryption, thus, it is efficient.