A Convertible Designated Verifible Blind Multi-signcryption Scheme

This paper presents a convertible blind multi-signcryption scheme without using any one-way hash function based on the security of three computationaly hard problems, namely Computationaly Diffie-hellman problem, Discrete Logarithimic Problem, Integer Factorisation problem .Only a designated verifier can verify the signcrypted text having the signcrypters public parameters. The size of the generated authenticated ciphertext is independent of the number of total participating signcrypters. The proposed scheme is convertible as it can easily produce the ordinary signcrypted text without the co-operation from the signer. The verification of the proposed scheme is less, thereby can be applicable in reallife scenarios.