Provably secure attribute based signcryption with delegated computation and efficient key updating

• Main Authors: HONG, Hanshu, XIA, Yunhao, SUN, Zhixin, LIU, Ximeng
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2017
• Subjects: Attribute based encryption; Efficient; Key evolution; Signcryption; Databases and Information Systems; Information Security
• Online Access: https://ink.library.smu.edu.sg/sis_research/3810; https://ink.library.smu.edu.sg/context/sis_research/article/4812/viewcontent/TIIS_Vol_11__No_5_19.pdf
• Institution: Singapore Management University

Equipped with the advantages of flexible access control and fine-grained authentication, attribute based signcryption is diffusely designed for security preservation in many scenarios. However, realizing efficient key evolution and reducing the calculation costs are two challenges which should be given full consideration in attribute based cryptosystem. In this paper, we present a key-policy attribute based signcryption scheme (KP-ABSC) with delegated computation and efficient key updating. In our scheme, an access structure is embedded into user’s private key, while ciphertexts corresponds a target attribute set. Only the two are matched can a user decrypt and verify the ciphertexts. When the access privileges have to be altered or key exposure happens, the system will evolve into the next time slice to preserve the forward security. What’s more, data receivers can delegate most of the de-signcryption task to data server, which can reduce the calculation on client’s side. By performance analysis, our scheme is shown to be secure and more efficient, which makes it a promising method for data protection in data outsourcing systems.