A new class UF of problems is introduced, strictly included in the class NP, which arises in the analysis of the time verifying the intermediate results of computations. The implications of the introduction of this class are considered. First of all, we prove that P  NP and establish that it needs to consider the problem “P vs UF” instead the problem “P vs NP”. Also, we determine the set-theor...

Efficient recipes for performing integer arithmetic are indispensable as they are widely used in several algorithms in diverse areas such as cryptology, computer graphics and other engineering areas. Hence our first object of study would be the most basic integer operations namely addition, subtraction, multiplication and division. We will start off with algorithms that are typically referred t...

Motivated by applications in cryptology K. Wei introduced in 1991 the concept of a generalized Hamming weight for a linear block code. In this paper we deene generalized Hamming weights for the class of convolutional codes and we derive several of their basic properties. By restricting to convolutional codes having a generator matrix G(D) with bounded Kronecker indices we are able to derive upp...

R. Rivest, A. Shamir and L. Adleman," A Method for Obtaining Digital Signatures and Public-Key Cryptosystems", Communications of the ACM, vol. 21, No. 2, pp. 120-126,1978. Wiener, M. : Cryptanalysis of short RSA secret exponents, IEEE Transactions on Information Theory 36, 553-558 (1990). Boneh, D. , Durfee, G. : Cryptanalysis of RSA with Private Key d Less Than N^0. 292, Advances in ...

Orthogonal arrays (OAs) are basic combinatorial structures, which appear under various disguises in cryptology and the theory of algorithms. Among their applications are universal hashing, authentica-tion codes, resilient and correlation-immune functions, derandomization of algorithms, and perfect local randomizers. In this paper, we give new bounds on the size of orthogonal arrays using Delsar...

We discuss a reduction notion relating the random oracles in two cryptographic schemes A and B. Basically, the random oracle of scheme B reduces to the one of scheme A if any hash function instantiation of the random oracle (possibly still oracle based) which makes A secure also makes B secure. In a sense, instantiating the random oracle in scheme B is thus not more demanding than the one for s...

We explore the security of blind signatures under aborts where the user or the signer may stop the interactive signature issue protocol prematurely. Several works on blind signatures discuss security only in regard of completed executions and usually do not impose strong security requirements in case of aborts. One of the exceptions is the paper of Camenisch, Neven and shelat (Eurocrypt 2007) w...

The publications sponsored by a scientific organization serve two main goals: fast publication of new research results and giving valuable credit to researchers for their works. The IACR is currently operating two levels for scientific publications: (1) the Journal of Cryptology publishes high-quality papers after a careful peer-reviewing process, and (2) the Crypto, Eurocrypt, and Asiacrypt (s...

This note is an exposition of reductions among the q-strong Diffie-Hellman problem and related problems. 1 The q-Strong Diffie-Hellman Problem We discuss reductions among the q-strong Diffie-Hellman (q-sDH) problem [1, 3] and related problems. We use the following notation: 1. G1 and G2 are two cyclic groups of prime order p. 2. g1 is a generator of G1 and g2 is a generator of G2. 3. ψ is an is...

This paper shows the implementation of cryptographic algorithm Advanced Encryption Standard (AES). The choice of AES algorithm considered the fact that it is the current advanced encryption standard, being selected after a long contest where various algorithms were cryptoanalized by the cryptology community. Furthermore, the AES was designed to allow expansion of the key when necessary, allow i...