Fundamenta Informaticae - Volume 161, issue 3

Authors: Canard, Sébastien | Trinh, Viet Cuong

Article Type: Research Article

Abstract: Identity-based cryptography has been introduced by Shamir at Crypto’84 to avoid the use of expensive certificates in certified public key cryptography. In such system, the identity becomes the public key and each user needs to interact with a designated authority to obtain the related private key. It however suffers the key escrow problem since the authority knows the private keys of all users. To deal with this problem, Riyami and Paterson have introduced, at Asiacrypt’03, the notion of certificateless public key cryptography. In this case, there is no need to use the certificate to certify the public key, and …neither the user nor the authority can derive the full private key by himself. There have been several efforts to propose a certificateless signature (CLS) scheme in the standard model, but all of them either make use of the Waters’ technique or of the generic conversion technique (proposed by Yum and Lee at ACISP’04) which both lead to inefficient CLS schemes. Besides making use of the Waters’ technique and the generic conversion technique (proposed also by Yum and Lee at ICCSA’04), there exists direct approaches to construct certificateless public key encryption (CLE) scheme in the standard model. In this paper, we introduce a new and direct approach to construct a CLS scheme in the standard model with constant-size of all parameters and having efficient computing time. We also show that the Boneh et al .’s identity-based encryption scheme secured in the standard model at EC’04 can be extended to the certificateless setting. Interestingly, the resulting scheme can be comparable with the existing CLE schemes in term of both efficiency and security. Show more

Keywords: Certificateless signature, certificateless encryption, standard model, strong type adversary

DOI: 10.3233/FI-2018-1701

Citation: Fundamenta Informaticae, vol. 161, no. 3, pp. 219-248, 2018

Authors: Masood, Zaheer | Majeed, Khalid | Samar, Raza | Raja, Muhammad Asif Zahoor

Article Type: Research Article

Abstract: The aim of this study is to develop an autonomous epidemic virus model to depict the transmission of malicious computer code in active networks with pre-existing immunity and quarantine as effective control strategies. Due to the rapid spread of computer viruses and a delay in the update of antivirus signature database, the role of quarantine as a controlling mechanism has gained importance. The existence of disease free equilibrium point and its stability, as well as the existence of endemic equilibrium point and its stability are explored in terms of basic reproduction number R 0 . The model exhibits two equilibria …points: disease free equilibrium and endemic equilibrium. Numerical simulations are performed to analyze the dynamics of the model in the presence of controlling mechanisms and in the absence of up-to-date antivirus software in terms of accuracy and convergence. The model interpretation invokes interesting inferences for effective quarantine strategy, with or without immunity and control mechanisms for security holes and zero-day vulnerabilities. Show more

Keywords: Virus Models, Stuxnet Virus, Epidemic, Industrial Systems, Computer Networks, Lyapunov Analysis

DOI: 10.3233/FI-2018-1702

Citation: Fundamenta Informaticae, vol. 161, no. 3, pp. 249-273, 2018

Authors: Michalak, Marcin | Ślęzak, Dominik

Article Type: Research Article

Abstract: Biclustering is a branch of data analysis, whereby the goal is to find two–dimensional subgroups in a matrix of scalars. We introduce a new approach for biclustering discrete and binary matrices on the basis of boolean function analysis. We draw the correspondence between non–extendable (maximal with respect to inclusion) exact biclusters and prime implicants of a discernibility function describing the data. We present also the results of boolean-style clustering of the artificial discrete image data. Some possibilities of utilizing basic image processing techniques for this kind of input to the biclustering problem are discussed as well.

Keywords: biclustering, boolean reasoning, discernibility, prime implicants, image processing

DOI: 10.3233/FI-2018-1703

Citation: Fundamenta Informaticae, vol. 161, no. 3, pp. 275-297, 2018

Authors: G S, Smrithy | Cuzzocrea, Alfredo | Balakrishnan, Ramadoss

Article Type: Research Article

Abstract: Cloud Collaboration Systems (CCS) offer efficient coordination among users to work on shared tasks in diverse distributed environments such as social networking, healthcare, wikis, and intelligent systems. Many cloud collaboration systems services are basically loosely coupled in nature. The flexibility of such CCS lead to various vulnerabilities in the system since the users are given broad access privileges. This may result in catastrophic activities from malicious insiders which in turn result in major misuse and abuse of information. While many sophisticated security mechanisms have been established to detect outsider threats in various systems, a very few works have been reported …so far to detect anomalous insider activities in complex CCS. In this paper, we propose a Sliding Window based Anomaly Detection using Maximum Mean Discrepancy or SWAD-MMD model to detect anomalous insider activities via access network of users and objects. The main scope of this paper is to exploit information theoretic and statistical techniques to address the above security issues in order to provide information theoretically provable security (i.e., anomaly detection with vanishing probability of error) based on graph based Maximum Mean Discrepancy (MMD) that measures the distance between mean embedding of distributions into a Reproducing Kernel Hilbert Space (RKHS). The theoretical aspects show that the proposed approach is suitable for detecting anomalous insider activities in dynamic cloud collaborative systems. Finally we validate the proposed model using two publicly available datasets fromWikipedia and present a performance evaluation in terms of accuracy of the proposed model. Show more

Keywords: Cloud Collaboration Systems, Maximum Mean Discrepancy, Reproducing Kernel Hilbert Space, Anomaly Detection, SWAD-MMD Model

DOI: 10.3233/FI-2018-1704

Citation: Fundamenta Informaticae, vol. 161, no. 3, pp. 299-316, 2018