A Practical Approach to Attaining Chosen Ciphertext Security  

作　　者：LI Jun CUI Guohua YANG Muxiang 

机构地区：[1]College of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China

出　　处：《Wuhan University Journal of Natural Sciences》2006年第6期1601-1604,共4页武汉大学学报（自然科学英文版）

基　　金：Supported by the National Natural Science Foun-dation of China (60403027)

摘　　要：Strong security in public key cryptography is not enongh; the encryption has to be achieved in an efficient way. OAEP or SAEP is only suitable for special applications （e. g. key transport）, and securely transporting message of any length is a challenge. Motivated by the hybrid encryption, we present a practical approach to achieve the （adaptively） chosen eiphertext security. The time cost of encryption/decryption of proposed scheme is similar to OAEP and the bandwidth of message recovery is 92% for standard security parameter, while RSA-OAEP is 84%. The scheme is also provably secure against adaptively chosen ciphertext attacks in the random oracle model. We conclude that the approach is practical in more extensive application.Strong security in public key cryptography is not enongh; the encryption has to be achieved in an efficient way. OAEP or SAEP is only suitable for special applications （e. g. key transport）, and securely transporting message of any length is a challenge. Motivated by the hybrid encryption, we present a practical approach to achieve the （adaptively） chosen eiphertext security. The time cost of encryption/decryption of proposed scheme is similar to OAEP and the bandwidth of message recovery is 92% for standard security parameter, while RSA-OAEP is 84%. The scheme is also provably secure against adaptively chosen ciphertext attacks in the random oracle model. We conclude that the approach is practical in more extensive application.

关 键 词：public-key encryption chosen ciphertext security random oracle model bandwidth of message recovery 

分 类 号：TP305[自动化与计算机技术—计算机系统结构]