Informatica

In this paper, we propose a mutual authentication scheme using nonce variable instead of Mac address and accompanying with token updates to improve the functionality. Lee et al. (2005a) and Shi et al. (2006) proposed the site authentication schemes by using the generating random numbers. The site authentication can identify a personal computer using LAN card's Mac address, but the Mac address is easily detected through Address Resolution Protocol in the Open Systems Interconnection model. Therefore, we propose an improved securer and efficient nonce-based authentication scheme providing mutual authentication to resist the replay attack, man-in-the-middle attack and Mac address attack.

In the presented paper, some issues of the fundamental classical mechanics theory in the sense of Ising physics are introduced into the applied neural network area. The expansion of the neural networks theory is based primarily on introducing Hebb postulate into the mean field theory as an instrument of analysis of complex systems. Appropriate propositions and a theorem with proofs were proposed. In addition, some computational background is presented and discussed.

Software localization is one of important tasks to insure a successful computer user experience. The paper discusses how localization of the software dialog text can be accelerated and how to raise the quality of software product localization. We also discuss the main features and common structure of localizable software resources, their formats and preparation for localization. As a result, we suggest applying a modified formalism of attribute grammars to describe localizable resources, taking the graphical user interface as a basic grammar structure, localizable strings and their parts as terminal symbols, and using the attributes to add important metainformation and context to the resources. The main principles of creation of such attribute grammars are presented.

A Group-Oriented Cryptosystem (GOC) allows a sender to encrypt a message sent to a group of users so only the specified sets of users in that group can cooperatively decrypt the message. Recently, Li et al. pointed out unauthorized sets in the receiving group can recover the encrypted messages in Yang et al.'s GOC; and they further repaired this security flaw. However, the improved GOC contains inexact security analysis. Further, conversion of the scheme into a threshold cryptosystem results in inefficiency. This study enhances Li et al.'s GOC, both in that it achieves the requirements of GOC but also that it can be efficiently converted into a threshold cryptosystem. Under the decisional Diffie–Hellman problem assumption, the proposed scheme is demonstrated to be provably secure against chosen plaintext attacks.

This study presents developed algorithm for assessment and updating estimates of parameters in the mathematical models of non-stationary processes (for instance, system ageing model, dynamic system models and so on) with respect of prior information and new obtained observations. Proposed algorithm for updating estimates of random parameters is based on modified application of Bayesian approach (BA). Developed algorithm was applied for Ignalina NPP Unit 2 RBMK-1500 reactor's closure of the gas-gap between the pressure tubes and the graphite bore probabilistic analysis.

A proxy signature scheme enables an original signer to delegate its signing capability to a proxy signer and then the proxy signer can sign a message on behalf of the original signer. Recently, in order to eliminate the use of certificates in certified public key cryptography and the key-escrow problem in identity-based cryptography, the notion of certificateless public key cryptography was introduced. In this paper, we first present a security model for certificateless proxy signature schemes, and then propose an efficient construction based on bilinear pairings. The security of the proposed scheme can be proved to be equivalent to the computational Diffie–Hellman problem in the random oracle with a tight reduction.

To suitably complete an image without seams, block effects, and artifacts, a novel exemplar-based image completion model employing partial differential equation (PDE) is proposed. Firstly, the novel model determines the processing order of exemplar according to a composite function, which is the product of the colour property and structure property in exemplar. Then the exemplar along a geometric structure is processed prior to other parts of the image. Secondly, the most similar exemplar is found in the CIELAB colour space, and the size of it is adaptively determined by the local textured information. Thirdly, a Poisson equation is adopted to remove the seams, block effects, and artifacts in the image generated by the exemplar-based model. Finally, a bi-directional diffusion PDE is used to assist the completion of lathy linear structure. Experimental results demonstrate that the novel model can properly reconstruct the target region while preserving the geometric structure without inducing block effects, which leads to its better performance than the conventional exemplar-based image completion models.

In 2008, based on the two-party Diffie–Hellman technique, Biswas proposed a contributory group key exchange protocol called the Group-DH protocol. This contributory property is an important one of group key agreement. Unfortunately, in this paper we show that the proposed Group-DH protocol is not a contributory group key exchange protocol. Therefore, we propose an improved group key exchange protocol with verifiably contributory property based on the same Diffie–Hellman technique. When an identical group key is constructed, each participant can confirm that his/her contribution is actually included in the group key. We show that the improved protocol is provably secure against passive attacks under the decisional Diffie–Hellman assumption. As compared to the previously proposed group key exchange protocols, our protocol provides contributiveness and the required computational cost is suitable for low-power participants in a network environment.

One of the major activities in software design is defining software architecture. Before designing software structure and software behavior we have to define its architecture. In this paper we have proposed three-tiered software architecture. This software architecture extends application logic tier with security. We have implemented two important security issues: authentication and authorization processes. These processes are implemented through software patterns. The software patterns have the particular place in the Proposed Software Architecture (PSA). In this paper, we have presented these software patterns and explained why they are important in PSA.

The asymmetric cipher protocol, based on decomposition problem in matrix semiring ℳ over semiring of natural numbers 𝒩 is presented. The security of presented cipher protocol is based on matrix decomposition problem (MDP), which is linked to the problem of solution of multivariate polynomial system of equations. Compromitation of proposed scheme relies on the solution of system of multivariate polynomial system of equations over the semiring of natural numbers 𝒩. The security parameters are defined, security analysis and implementation is presented.