New secure cetificateless signcryption scheme without pairing.

The known certificateless signcryption schemes have many problems, for example, lack of security, low computational cost and so on. This paper proposed a new secure certificateless signcryption scheme without pairings, which was based on Sharmila's. And it was provably secure in the random oracle model ( ROM). The proposed scheme did no use of pairing and exponentation. And compared with the most efficient scheme, the proposed one just needs 2 more point multiplications under the secure circumstance. [ABSTRACT FROM AUTHOR]