A generic construction of identity-based signcryption

Signcryption is a cryptographic primitive that fulfills both the functions of digital signature and public key encryption simultaneously, at a cost significantly lower than that required by the traditional signature-then-encryption approach. In this paper, we propose the first generic construction of identity-based signcryption (GCIS) by using identity-based key encapsulation mechanism (ID-KEM), data encapsulation mechanism (DEM), and identity-based signature schemes (ID-SIG). We prove that our construction satisfies confidentiality and unforgeability. We describe an instantiation of our construction that is secure in the standard model. Our instantiation also solves an open problem proposed by Yuen and Wei.