Showing papers on "Plaintext-aware encryption published in 1988"

Non-interactive zero-knowledge and its applications

Abstract: We show that interaction in any zero-knowledge proof can be replaced by sharing a common, short, random string. We use this result to construct the first public-key cryptosystem secure against chosen ciphertext attack.

Is the data encryption standard a group? (Results of cycling experiments on DES)

Abstract: The Data Encryption Standard (DES) defines an indexed set of permutations acting on the message space ℳ ={0,1}64. If this set of permutations were closed under functional composition, then the two most popular proposals for strengthening DES through multiple encryption would be equivalent to single encryption. Moreover, DES would be vulnerable to a known-plaintext attack that runs in 228 steps on the average. It is unknown in the open literature whether or not DES has this weakness.

Proving security against chosen cyphertext attacks

Abstract: The relevance of zero knowledge to cryptography has become apparent in the recent years. In this paper we advance this theory by showing that interaction in any zero-knowledge proof can be replaced by sharing a common, short, random string. This advance finds immediate application in the construction of the first public-key cryptosystem secure against chosen ciphertext attack.Our solution, though not yet practical, is of theoretical significance, since the existence of cryptosystems secure against chosen ciphertext attack has been a famous long-standing open problem in the field.

A public-key cryptosystem based on the difficulty of solving a system of nonlinear equations

Abstract: This paper proposes a new public-key cryptosystem based on the difficulty of solving a system of nonlinear equations. The proposed cryptosystem has the following features: 1) The public-key is a nonlinear transform from a plaintext to a ciphertext in the form of rational functions. 2) The complexity of both encryption and decryption is O(m2), where m is the plaintext length. 3) Digital signature is possible. The two previously proposed systems based on the matrix decomposition and the squared matrix are special cases of the proposed system. The reliability of the cryptosystem when nonlinearity is limited to the polynomial form is discussed. Next, a publickey cryptosystem based on the difficulty of solving a system of nonlinear equations with rational functions is proposed, its decryption algorithm is studied, and the conditions for this cryptosystem to ensure reliability are derived. Finally, the computational complexity of encryption and decryption, the description volume of public and secret keys, and the possibility of digital signature are studied.

A new probabilistic encryption scheme

Abstract: In this paper we present a new probabilistic public key cryptosystem. The system is polynomially secure. Furthermore, it is highly efficient in that it's message expansion is l+(k-1)/1, where k is the security parameter and l the length of the encrypted message. Finally, the system can be used to sign signatures.