关键词: 对称密码, 分组密码, 双明文加密, 穷举攻击, 防篡改

Abstract:

The security of traditional symmetric cryptosystem lies entirely in the secrecy of encryption keys. DES, 3DES, IDEA and AES, which are symmetric algorithms commonly adopted, all make their ways from one single set of plaintexts to one single set of ciphertexts. Owing to the simplex mode of information utilization, the amount of information transmitted is far from perfection. Also, they are unable to provide separate information when faced with the situation where the demand of branch conditions is not well met. In the view of the foregoing perspectives, this paper introduces double plaintext and gives a brief introduction of its encryption method and operational principle. And the encryption algorithm is divided into several sub-algorithms with each of them described carefully in terms of function and safety considerations. The paper also summarizes similarities and differences between familiar symmetric encryption algorithms and the one this paper presents. Meanwhile a few application scenarios are demonstrated to help form an understanding of the prospect of the algorithm. In the last part, this paper analyzes the strength and weakness this algorithm can bring and gives a future study direction. This encryption algorithm helps to multiply the amount of information being transmitted, and to bring in a method of writing back plaintext alternatively with high efficiency. And it innovates in preventing intruders from brute-force attack. Additionally, hash arithmetic is also introduced to ensure data integrity, resist tamper and complete inspection. So this method is well advanced technically.

Key words: symmetric cryptography, block cryptography, double plaintext, brute-force attack, tamper resistance