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October 2010, No. 4 |
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2009 Index
The International Arab Journal for Information Technology Vol. 6
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Measurement of V2oIP over Wide Area
Network between Countries Using
Soft Phone and USB Phone
Mohd Ismail
Department of MIIT, University of Kuala Lumpur, Malaysia Abstract: In this research, we propose an architectural solution to integrate the video voice over IP services in campus environment network and tested over LAN and WAN. Voice over IP technology has become a discussion issue for this time being. Today, the deployment of this technology on an organization truly can give a great financial benefit over traditional telephony. Therefore, this study is to analyze the V2oIP and investigate the performance areas evolved with the quality of service delivered by video phone system over LAN and WAN. This study focuses on quality of voice and video, packet loss, delay time and jitter through the USB video phone and soft phone over LAN and WAN. In this study, network management system is used to monitor and capture the performance of V2oIP between LAN and WAN. In addition, the most apparent of implementing soft phone and USB video phone platform is to define the best achievement between LAN and WAN that can be used in operational environment. Based on the finding result, it shows that users may experience V2oIP quality service degradations due to delays and losses in WAN compare to LAN. Keywords: V2oIP, jitter, delay, packet loss, CPU, LAN, WAN, and NMS Received May 27, 2008; accepted September 1, 2008 Full Text |
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Evaluation of Text Clustering
Methods Using WordNet
Abdelmalek Amine1,2, Zakaria Elberrichi1, and Michel Simonet3
1EEDIS Laboratory, Department of Computer Science, UDL University, Algeria
2Department of Computer Science, UTMS University, Algeria
3IN3S, Joseph Fourier University, France
Abstract: The increasing number of digitized texts presently available notably on the Web has developed an acute need in text mining techniques. Clustering systems are used more and more often in text mining, especially to analyze texts and to extract knowledge they contain. With the availability of the vast amount of clustering algorithms and techniques, it becomes highly confusing to a user to choose the algorithm that best suits its target dataset. Actually, it is very hard to define which algorithms work the best, since results depend considerably on the application and on the kinds of data at hand. In this paper, we propose, study and compare three text clustering methods: an ascending hierarchical clustering method, a SOM-based clustering method and an ant-based clustering method, all of these based on the synsets of WordNet as terms for the representation of textual documents. The effects of these methods are examined in several experiments using 3 similarity measurements: the cosine distance, the Euclidean distance and the manhattan distance. The reuters-21578 corpus is used for evaluation. The evaluation was done, by using the F-measure. The results obtained show that the SOM-based clustering method using the cosine distance provides the best results.
Keywords: Text clustering, similarity, WordNet, reuter-21578, and F-measure. Received February 24, 2009; accepted August 3, 2009
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A Modified High Capacity Image Steganography Technique Based on Wavelet Transform
Ali Al-Ataby1 and Fawzi Al-Naima2
1Department of Electrical Engineering and Electronics, University of Liverpool, UK
2Department of Computer Engineering, Nahrain University, Iraq
Abstract: Steganography is the art and science of concealing information in unremarkable cover media so as not to arouse an eavesdropper’s suspicion. It is an application under information security field. Being classified under information security, steganography will be characterized by having set of measures that rely on strengths and counter measures (attacks) that are driven by weaknesses and vulnerabilities. Today, computer and network technologies provide easy-to-use communication channels for steganography. The aim of this paper is to propose a modified high-capacity image steganography technique that depends on wavelet transform with acceptable levels of imperceptibility and distortion in the cover image and high level of overall security.
Keywords: Steganography, security, wavelets, cryptography, and information hiding. Received August 17, 2008; accepted August 3, 2009
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Attack and Construction of Simulator for Some of Cipher Systems Using Neuro-Identifier
Khaled Alallayah1, Mohamed Amin1, Waiel Abd El-Wahed2, and Alaa Alhamami3
1Department of Mathematical & Computer Science, Al Menoufia University, Egypt
2Department of Computer Science, Al Menoufia University, Egypt
3Faculty of Computing Studies, Amman Arab University for Graduate Studies, Jordan
Abstract: The problem in cryptanalysis can be described as an unknown and the neural networks are ideal tools for black-box system identification. In this paper, a mathematical black-box model is developed and system identification techniques are combined with adaptive system techniques, to construct the Neuro-Identifier. The Neuro-Identifier is discussed as a black-box model to attack the target cipher systems. In this paper a new addition in cryptography. Has been presented, and the methods of classical and stream cryptosystems are discussed. The constructing of Neuro-Identifier mode is to achieve two objectives: the first one is to emulator construction Neuro-model for the target cipher system, while the second is to (cryptanalysis) determine the key from given plaintext-ciphertext pair.
Keywords: Neuro-Identefier, classical cipher, stream cipher, black box, emulation, and cryptanalysis. Received May 27, 2008; accepted September 1, 2008 |
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Multilayer Neural Network-Burg Combination
for Acoustical Detection of Buried Objects
Mujahid AL-Azzo1 and Lubna Badri2
1Faculty of Engineering Technology, Zarqa Private University, Jordan
2Faculty of Engineering, Philadelphia University, Jordan
Abstract: A Burg technique is employed to model the long wavelength localization and imaging problem. A Burg method is used as a high resolution and stable technique. The idea of in-line holography is used to increase the ratio of the signal to noise due to the effect of concealing media that decreases the value of the received signal. The performance is enhanced by using multilayer neural network for noise reduction. The aim of using multilayer neural network is to extract the essential knowledge from a noisy training data. Theoretical and experimental results have showed that preprocessing the noisy data with multilayer neural network will decrease the effect of noise as much as possible. Applying the enhanced data to spectral estimation methods has improved the performance of the model. A comparison is made for the two cases: with and without application of neural network for different values of signal to noise ratio. Also, the performance is investigated for different numbers of samples. Keywords: Multilayer neural networks, holographic imaging, burg method, and modelling. Received November 13, 2008; accepted August 3, 2009 |
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A Performance Comparison of MD5
Authenticated Routing Traffic with
EIGRP, RIPv2, and OSPF
Khalid Abu Al-Saud1, 2, Hatim Tahir2, Moutaz Saleh1, and Mohammed Saleh1
1Department of Computer Science and Engineering College of Engineering, Qatar University, Qatar
2Department of Computer Science, Faculty of Information Technology, Malaysia
Abstract: Routing is the process of forwarding data across an inter-network from a designated source to a final destination. Along the way from source to destination, at least one intermediate node is considered. Due to the major role that routing protocols play in computer network infrastructures, special cares have been given to routing protocols with built-in security constraints. In this paper, we conduct performance evaluation comparisons on message digest 5 authenticated routing traffic with respect to EIGRP, RIPv2 and OSPF protocols. A network model of four Cisco routers has been employed with an ON/OFF traffic model used to describe text files transmissions over the network. Eventually, analysis tool has been developed and used to measure the average delay time and average jitter. The collected results show that the average delay time and jitter in the secured message digest 5 case can become significantly larger when compared to the non-secured case even in steady state conditions. Among all, the secured OSPF protocol shows the highest performance even when the system is extremely overloaded. Keywords: Performance, MD5, EIGRP, RIPv2, and OSPF. Received November 3, 2008; accepted February 25, 2009 |
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Implementation of a Speech Coding
Strategy for Auditory Implants
Lamia Bouafif, Kais Ouni, and Noureddine Ellouze
Signal Processing Laboratory, Engineering Faculty of Tunis, Tunisia
Abstract: In this paper we present the conception and the implementation of a speech processing interface for cochlea prosthesis. This module is based on a numerical speech processing algorithm which modelizes the infected ear and generates the stimulus signals for the cilia cells (brain). This interface uses a gammachirp filter bank constituted of 16 band pass filters based on IIR filters. The central frequencies and ERB bands are computed with Glasberg and Moore models; however stimulus signals are selected after a spectral energy analysis of each channel. The energy and the amplitude of the selected BFG filter bank outputs are quantized and transmitted to the cochlea electrodes. To validate our work, we tested it on vowels, consonants then on several words pronounced by different speakers. The results demonstrated a degree of discrimination and interferences between different sounds especially in multi speaker environment.
Keywords: Cochlea prosthesis, stimulus, gammatone filter, gammachirp, and speech coding. Received February 8, 2009; accepted May 27, 2009 |
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JAM: Justifiable Allocation of Memory with Efficient Mounting and Fast Crash Recovery
for NAND Flash Memory File Systems
Sanam-Shahla Rizvi and Tae-Sun Chung
School of Information and Computer Engineering, Ajou University, Korea
Abstract: Flash memory is small size, lightweight, shock-resistant, non-volatile, and consumes little power. Flash memory therefore shows promise for use in storage devices for consumer electronics, mobile computers and embedded systems. Even though, flash memory has many attractive features but issues on performance and data integrity are becoming more critical to address by researchers. First, the rapidly increasing capacity of flash memory imposes long mount time delay for normal start-up and in case of crash recovery. Second, large main memory requirement for keeping file system mapping data structure becoming significant issue with growth in size of flash memory. In this paper, we discuss related problems in detail, and propose novel mechanism for high performance and system reliability by effective metadata management, efficient mounting, fast crash recovery, and reduced RAM footprints for log structured NAND flash memory based file systems, called justifiable allocation of memory. The trace driven simulation results show the significantly improved performance for mounting and crash recovery time with reduced main memory space required by our proposed justifiable allocation of memory scheme compared to well-known JFFS2 and YAFFS2 flash file systems.
Keywords: Consumer electronics, embedded systems, memory management, system crash recovery, system reliability, and system performance.
Received December 18, 2008; accepted July 26, 2009
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Brightness Preserving Image Contrast Enhancement using Weighted Mixture of Global and Local Transformation Functions
Hasanul Kabir1, Abdullah Al-Wadud2, and Oksam Chae1
1Department of Computer Engineering, Kyung Hee University, Korea
2Industrial and Management Engineering Division, Hankuk University of Foreign Studies, Korea
Abstract: Transformation functions utilizing the global information content of an input image have been long serving contrast enhancement by stretching the dynamic range of intensity levels. Other transformation functions focus on local information content to correct image details, such as edges and texture. In this paper, an effective method for image contrast enhancement is presented with a mapping function, which is a mixture of global and local transformation functions that improve both the brightness and fine details of the input image. The final mapping function incorporates a local intensity-pair distribution generated expansion function from each image block to control the enhancement of image details that the global transformation function alone may fail to improve. Contribution from the global transformation function preserves the overall image brightness and contrast stretching. Experiments show that the proposed method competes well with the existing enhancement methods, both subjectively and quantitatively.
Keywords: Contrast enhancement, global transformation function, local transformation function, and intensity pair. Received March 29, 2009; accepted August 4, 2009
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Hybrid Computing Algorithm in
Representing Solid Model
Muhammad Matondang and Habibollah Haron
Department of Modeling and Industrial Computing, Universiti Teknologi Malaysia, Malaysia
Abstract: This paper presents an algorithm, which is a hybrid-computing algorithm in representing solid model. The proposed algorithm contains two steps namely reconstruction and representation. In the reconstruction step, neural network with back propagation has been applied to derive the depth values of solid model that was represented by the given two-Dimensional (2D) line drawing. And then in the representation step, once the depth value was derived, the mathematical modeling was used to generate the mathematical models to represent the reconstructed solid model. The algorithm has been tested on a cube. Totally, there are eighty-three cubes has been used on the development of neural network model and six mathematical equations yielded to represent each one cube. The proposed algorithm successfully takes the advantages of neural network and mathematical modeling in representing solid model. Comparison analysis conducted between the algorithm and skewed symmetry model shows that the algorithm has more advantages in term of the ease of the uses and in simplifying the use of mathematical modeling in representing solid model. Keywords: Solid model, reconstruction, representation, neural network, mathematical modeling, and hybrid computing. Received June 19, 2008; accepted February 25, 2009 Full Text |
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A Novel Radon-Wavelet Based OFDM
System Design and Performance Under
Different Channel Conditions
Abbas Kattoush
EE Engineering Department, Tafila Technical University, Jordan
Abstract: Finite Radon Transform mapper has the ability to increase orthogonality of sub-carriers, it is non sensitive to channel parameters variations, and has a small constellation energy compared with conventional Fast Fourier Transform based orthogonal frequency division multiplexing. It is also able to work as a good interleaver which significantly reduces the bit error rate. Due to its good orthogonality, discrete wavelet transform is used for orthogonal frequency division multiplexing systems which reduces inter symbol interference and inter carrier interference. This eliminates the need for cyclic prefix and increases the spectral efficiency of the design. In this paper both Finite Radon Transform and Discrete Wavelet Transform are implemented in a new design for orthogonal frequency division multiplexing. The new structure was tested and compared with conventional Fast Fourier Transform -based orthogonal frequency division multiplexing, Radon-based orthogonal frequency division multiplexing, and discrete wavelet transform -based orthogonal frequency division multiplexing for additive white Gaussian noise channel, flat fading channel, and multi-path selective fading channel. Simulation tests were generated for different channels parameters values. The obtained results showed that proposed system has increased spectral efficiency, reduced inter symbol interference and inter carrier interference, and improved bit error rate performance compared with other systems. Keywords: Discrete Wavelet Transform, Finite Radon Transform, radon based OFDM, DWT based OFDM, and OFDM.
Received April 8, 2009; accepted August 4, 2009 |
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Improving Web Services Security Models
Sawsan Abu-Taleb and Hossam Mustafa
Al-Balqa' Applied University, Jordan
Abstract: Web services are considered one of the main technologies which emerged in recent years, they provide an application integration technology that allows business applications to communicate and cooperate over the Internet. Web services encouraged existent architectures to adopt as one of the most important technologies; Portals, providing content aggregation from various web services sources for providing useful information to users. The distributed sources of web services aggregated into users' pages provide a component model architecture, which allows the plugging of components in infrastructure, which are referred to as portlets. This paper defines effective models for securing portlet contents by defining an access control list for each portlet, which will looks into the access control of web services, and authentication of web services consumers. In addition, this paper introduces a design for trusted authority that will be responsible for fair contract exchange between portlet producers and consumer; thus, defining a single sign-on model, which is responsible for authenticating remote portlets requests.
Keywords: Web services, WSRP, single-sign-on, security, and e-contract. Received July 23, 2008; accepted May 17, 2009 |
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Framework for Intrusion Detection in
IEEE 802.11 Wireless Mesh Networks
Shafiullah Khan1, 2, Kok-Keong Loo1, and Zia Ud Din3
1School of Engineering and Design, Brunel University, UK
2Kohat University of Science and Technology, Pakistan
3Gomal University, Pakistan
Abstract: Intrusion detection system is one of the possible solutions to timely detect the intrusions and alarm for appropriate action. So far many intrusion detection systems have been proposed for ad-hoc networks, however due to the different characteristics, such intrusion detection systems cannot perform well in wireless mesh networks environment. In this paper, we propose a new framework of intrusion detection systems exclusively for wireless mesh networks. This paper will serve as a baseline guide for investigating intrusion detection systems for large scale multi-hop wireless broadband networks.
Keywords: Wireless mesh network, intrusion detection, and security. Received May 12, 2009; accepted August 3, 2009
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