A Ciphertext Policy Attribute Based Signcryption Scheme with Secure and Flexible Key Evolving

Data encryption and signature technique can provide secure data protection and verification during data transmission. A data owner can choose to generate a legal signature first, then encrypt it before data sharing. However, the traditional sign-then-encrypt method not only occupies much more computation resources on digital devices, but also brings about high computation cost to the whole communication systems when data verification and key updating happens. In this paper, we utilize CP-ABE and ABS to propose a CP-ABSC scheme, which reduces the calculation burden for users in multi-party communication scenario. By security analysis, our scheme is demonstrated to realize confidentiality, unforgeability with resistance of collusion attack and traitor tracing.