Abstract:

When sensitive information is safely transmitted in the public network communication system,the overconcentrated privilege between the communication parties can sometimes cause cheating,but such safety problem can be solved by the group signcryption scheme. Based on the ID-based cryptography and elliptic curve discrete logarithm problem,a new ID-based group signcryption scheme is proposed. In the scheme,any t or more than t signcryption group members collaboratively can generate a valid group signcryption,and less than t can not generate a valid group signcryption;any w or more w receiver group members collaboratively can verify the legitimacy of the group signcryption and recover the encrypted message. Through security analysis of the proposed program,the program has authentication，confidentiality,data integrity,non -repudiation and unforgeability and other features.

Key words: ID-based, threshold scheme, signcryption, elliptic curve discrete logarithm problem