INFORMATICA Informatica 0868-4952 0868-4952 VU inf23102 10.15388/Informatica.2012.347 Research article Identity-Based Key-Insulated Signcryption Chen Jianhong Chen Kefei chen-kf@cs.sjtu.edu.cn Wang Yongtao wyt_sjtu@yahoo.com.cn Li Xiangxue xxli@cs.ecnu.edu.cn Long Yu longyu@sjtu.edu.cn Wan Zhongmei wan-zmei@163.com Department of Computer Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China School of Computer Engineering, Huaiyin Institute of Technology Shanghai Key Laboratory of Scalable Computing and System, Shanghai Jiao Tong University Department of Computer Science and Technology, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China College of Science, Hohai University, 1 Xikang Road, Nanjing 210098, China 01 01 2012 23 1 27 45 01 04 2009 01 09 2011

Key-insulated cryptography is an important technique to protect private keys in identity-based (IB) cryptosytems. Despite the flurry of recent results on IB key-insulated encryption (IBKIE) and signature (IBKIS), a problem regarding the security and efficiency of practicing IBKIE and IBKIS as a joint IB key-insulated signature/encryption scheme with a common set of parameters and keys remains open. To deal with the above question, we propose an identity-based key-insulated signcryption (IBKISC) scheme. Compared with the Sign-then-Encrypt (StE) and Encrypt-then-Sign (EtS) using IBKIE and IBKIS in the standard model, our proposed IBKISC scheme is the fastest with the shortest ciphertext size.

 key-insulated signcryption standard model