Research On Multi-Receivers Signcryption Schemes

Signcryption can achieve both the signature and encryption function in a logic step and is with the cost lower than common way "first signature and then encryption", thus is an ideal way to achieve information storage and transmitted secretly and verifiably. In some situation a message needs to be sent to more than one legal recipient at the same time. A signer expects his signature to be validated only by these appointed recipients. Every receiver also hopes he can easily verify the signcryption respectively without any others' help, but those irrelevant ones can not without the signer's or his cooperation.Signcryption has many applications, such as in electronical funds transfer systems, electronical auction and electronical voting etc.The following are the results of the thesis:(1) A signcryption scheme from bilinear pairings is proposed, which can satisfy security, verifiability and non-deniable at the same time. The security analysis of the scheme is also analyzed.(2) The related technology of proxy signature is analyzed. Finally, by introducing the idea of signcryption, we propose a proxy signcryption scheme and analyze the security of the scheme,In the scheme, every receiver can verify the signcryption repectively.