Group-oriented settings multisigncryption scheme with threshold designcryption
Signcryption supports the authenticity and confidently in a single logic step and it has more efficient cost than the signature-then-encryption approach. Currently signcryption schemes only support a peer to peer secure message transfer between single users, and thus it cannot be adapted to the group users in multiple senders and receivers. In this paper, we propose a group-oriented multisigncryption scheme with threshold designcryption in multi-users setting, which combines the threshold secret sharing technology, zero knowledge proof for the bilinear map equality of two discrete logarithms, multi-signature and identity-based signcryption schemes. The ciphertext in the proposed scheme is computed by all the m members in sender group, and it can be decrypted only by t-out-of-n members in receiver group. We prove the security of the proposed scheme in several models including semantic security, unforgeability, public ciphertext authenticity and verifiability.
multisigncryption threshold designcryption semantic secure unforgeability bilinear pairing