Abdulhadi Shoufan

Natural Language Processing for Dialectical Arabic: A Survey

This paper presents a wide literature review of natural language processing for dialectical Arabic. Four main research areas were identified and the dialect coverage in research work was outlined. The paper can be used as a quick reference to identify relevant contributions that address a specific NLP aspect for a specific dialect.

Power trace alignment for cryptosystems featuring random frequency countermeasures

Using a random number generator for the control of the input clock in FPGA-based cryptographic systems causes misalignments in the power traces, which can be exploited as a countermeasure against Correlation Power Analysis (CPA). In this paper we propose a method to process such misaligned traces in order to identify power peaks dynamically and to align them partially. After removing the misalignment caused by such a countermeasure and a subsequent trace processing the cryptosystem may easily be attacked by the CPA method. By means of a comprehensive measurement and analysis process of an AES 128 bit block cipher we demonstrate that the proposed method can deal with misaligned traces very efficiently.

Secure Communication in Civil Drones

The drone technology is attracting an increasing attention in civil applications. Secure communication is a critical requirement in many scenarios to provide an acceptable level of data confidentiality, integrity, and availability. In this chapter we first present a security analysis of civil drones. Then, a light-weight hardware solution is proposed to assure the confidentiality and integrity of both command data sent by the ground station and payload data transmitted by the drone. Using the developed prototype, finally, we investigate the impact of hardware accelerators on the power consumption of these power-constrained devices. We show that the advantage of hardware as a power-efficient computation platform is not necessarily valid for drones due to the extra hardware weight.

A fault attack on a hardware-based implementation of the secure hash algorithm SHA-512

Cryptographic hash functions are frequently used as basic components in cryptographic schemes such as message authentication codes, one-time signature schemes, and random number generators. In such applications the input to the hash function is a secret key or secret data. An investigation of the hash function against implementation attacks in such cases is indispensable. This paper presents a fault attack on the secure hash algorithm using the example of SHA-512. A fault model is proposed that relies on flipping two control bits to reduce the round number of the SHA-512 algorithm. By means of this attack the first data block can be extracted completely. The attack was applied to a keyed-hash message authentication code to reveal its secret key. A countermeasure is proposed to detect and prevent the attack. The attack and the countermeasure were evaluated for an FPGA implementation.

A hardware security module for quadrotor communication

This paper presents a hardware architecture for secure quadrotor communication. Both, the control data sent by the ground station and the information data sent by the quadrotor are encrypted and authenticated. The system is implemented on an FPGA and integrated on an extension board. The board is embedded into a self-constructed quadrotor based on the project Next-Generation Universal Aerial Video Platform.

Toward Modeling the Intrinsic Complexity of Test Problems

The concept of intrinsic complexity explains why different problems of the same type, tackled by the same problem solver, can require different times to solve and yield solutions of different quality. This paper proposes a general four-step approach that can be used to establish a model for the intrinsic complexity of a problem class in terms of solving time. Such a model allows prediction of the time to solve new problems in the same class and helps instructors develop more reliable test problems. A complexity model, furthermore, enhances understanding of the problem and can point to new aspects interesting for education and research. Students can use complexity models to assess and improve their learning level. The approach is explained using the K-map minimization problem as a case study. The implications of this research for other problems in electrical and computer engineering education are highlighted. An important aim of this paper is to stimulate future research in this area. An ideal outcome of such research is to provide complexity models for many, or even all, relevant problem classes in various electrical and computer engineering courses.

Efficient Generic Construction of Forward-Secure Identity-Based Signature

We propose an efficient generic construction of forward-secure identity-based signature (FSIBS) that ensures unforgeability of past signatures in spite of the exposure of the current signing key. Our construction, supported by formal security analysis, brings about concrete FSIBS schemes which are more efficient than existing schemes in the literature. Especially, one of our instantiations of FSIBS based on discrete-log primitive turns out to be the most efficient among existing ones. As a secondary contribution, we refine the definition of security of FSIBS in such a way that users in the system can freely specify time periods over which their signing keys evolve.

Consumer Opinions on Short-Interval Charging for Pay-TV over IPTV

The short-interval charging model is a customer-oriented charging model for pay-TV over Internet Protocol Television (IPTV). In contrast to conventional pay-TV models such as subscription-based pay-TV, pay-per-view and video on demand, this model allows charging for very short viewing intervals in the range of seconds. This paper presents the results of a survey in order to assess the acceptance of this charging model. About 33% of the survey participants favor short-interval charging over traditional models such as subscription, video on demand, and pay-per-view.

On inter-Rater reliability of information security experts

The Confidentiality-Availability-Integrity (CIA) triad is a time-honored warhorse of security analysis. Qualitative assessment of security requirements based on the CIA triad is an important step in many standard procedures for selecting and deploying security controls. However, little attention has been devoted to monitoring how the CIA triad is used in practice, and how reliable are experts assessment that make use of it. In this paper, a panel of 20 security experts was asked to use the CIA triad in 45 practical security scenarios involving UAV-to-ground transmission of control and information data. The experts responses were analyzed using Fleiss kappa, a specific statistics test for inter-rater reliability. Results show agreement to be low (from 13.8% to 20.1% depending on the scenario), but higher on scenarios where the experts majority estimates tight security to be needed. Low number of polled experts is found to affect inter-rater reliability negatively, however, increasing this number beyond ten does not provide additional reliability. A bias to give a specific rate could be identified with 14 out of the 20 experts. The six unbiased experts showed a higher inter-rater agreement. These findings suggest that (i) there is no guaranteed safety in numbers for recruiting security expert panels and (ii) expert selection for security rating processes should include verification of agreement level on toy problems for all subsets of the panel to highlight subsets showing high inter-rater agreement.

An intrinsic complexity model for the problem of total resistance determination

Any exam problem shows a specific level of intrinsic complexity that affects its solving time. This paper investigates the factors that affect the intrinsic complexity of determining the total resistance of a resistive circuit. A sample of 46 circuits was generated and solved by 27 students with time recording. Regression analysis showed that the solving time is significantly affected by the number of arithmetic operations required to solve the problem, by the value range of the resistors, as well as by the inconsistency of the given resistor units. Other factors that reflect the circuit topology including the number of circuit nodes and branches are either correlated with the number of arithmetic operations or insignificant in the regression analysis. The outcome of the study is a complexity model that can be used to predict the solving time of new problems of the same class which allows to develop more reliable exam problems. Different ways to control the complexity level are discussed in depth.