Recent research has shown the possibility of using smartphones' sensors and accessories to extrac... more Recent research has shown the possibility of using smartphones' sensors and accessories to extract some behavioral attributes such as touch dynamics, keystroke dynamics and gait recognition. These attributes are known as behavioral biometrics and could be used to verify or identify users implicitly and continuously on smartphones. The authentication systems that have been built based on these behavioral biometric traits are known as active or continuous authentication systems. This paper provides a review of the active authentication systems. We present the components and the operating process of the active authentication systems in general, followed by an overview of the state-of-theart behavioral biometric traits that used to develop an active authentication systems and their evaluation on smartphones. We discuss the issues, strengths and limitations that associated with each behavioral biometric trait. Also, we introduce a comparative summary between them. Finally, challenges and open research problems are presented in this research field.
This paper proposes a system to extract images from web pages and then detect the skin color regi... more This paper proposes a system to extract images from web pages and then detect the skin color regions of these images. As part of the proposed system, using BandObject control, we built a Tool bar named "Filter Tool Bar (FTB)" by modifying the Pavel Zolnikov implementation. The Yahoo! Team provides us with the Yahoo! SDK API, which also supports image search and is really useful. In the proposed system, we introduced three new methods for extracting images from the web pages (after loading the web page by using the proposed FTB, before loading the web page physically from the localhost, and before loading the web page from any server). These methods overcome the drawback of the regular expressions method for extracting images suggested by Ilan Assayag. The second part of the proposed system is concerned with the detection of the skin color regions of the extracted images. So, we studied two famous skin color detection techniques. The first technique is based on the RGB color space and the second technique is based on YUV and YIQ color spaces. We modified the second technique to overcome the failure of detecting complex image's background by using the saturation parameter to obtain an accurate skin detection results. The performance evaluation of the efficiency of the proposed system in extracting images before and after loading the web page from localhost or any server in terms of the number of extracted images is presented. Finally, the results of comparing the two skin detection techniques in terms of the number of pixels detected are presented.
Mobile ip (mip) is an internet protocol that allows mobile nodes to have continuous network conne... more Mobile ip (mip) is an internet protocol that allows mobile nodes to have continuous network connectivity to the internet without changing their ip addresses while moving to other networks. The packets sent from correspondent node (cn) to a mobile node (mn) go first through the mobile node's home agent (ha), then the ha tunnels them to the mn's foreign network. One of the main problems in the original mip is the triangle routing problem. Triangle routing problem appears when the indirect path between cn and mn through the ha is longer than the direct path. This paper proposes a new technique to improve the performance of the original mip during the handoff. The proposed technique reduces the delay, the packet loss and the registration time for all the packets transferred between the cn and the mn. In this technique, tunneling occurs at two levels above the ha in a hierarchical network. To show the effectiveness of the proposed technique, it is compared with the original mip and another technique for solving the same problem in which tunneling occurs at one level above the ha. Simulation results presented in this paper are based on the ns2 mobility software on linux platform. The simulations results show that our proposed technique achieves better performance than the others, considering the packet delay, the packet losses during handoffs and the registration time, in different scenarios for the location of the mn with respect to the ha and fas.
Mobile communication devices have become popular tools for gathering and disseminating informatio... more Mobile communication devices have become popular tools for gathering and disseminating information and data. When sensitive information is exchanged using SMS, it is crucial to protect the content from eavesdroppers as well as ensuring that the message is sent by a legitimate sender. Using an encryption technique to secure SMS data increases its length and accordingly the cost of sending it. This paper provides a hybrid compression encryption technique to secure the SMS data. The proposed technique compresses the SMS to reduce its length, then encrypts it using RSA algorithm. A signature is added to the encrypted SMS for signing it to differentiate it from other SMS messages in SMSINBOX. The experimental results which are based on Symbian OS show that the proposed technique guarantees SMS data security without increasing its size.
Web forms can be one of the most common sources of problems in web applications. This paper prese... more Web forms can be one of the most common sources of problems in web applications. This paper presents a state-based approach for testing web forms, in which a finite state machine model is proposed to represent the transitions between web forms within a web application. Using the proposed model, a page transition table is constructed, then, based on this table, a page transition tree is constructed. Using this tree, a set of test cases (scenarios) is generated. Executing these scenarios assists the tester in detecting several web forms errors, such as empty form fields, wrong input data, incorrect input data format, and database access. Also, the paper presents a description of the automated web form testing system that implements the proposed state-based web form testing approach. Finally, the paper presents a case study that demonstrates the working of the developed system and its error exposing ability.
The Short Message Service (SMS) have an important economic impact for end users and service provi... more The Short Message Service (SMS) have an important economic impact for end users and service providers. Spam is a serious universal problem that causes problems for almost all users. Several studies have been presented, including implementations of spam filters that prevent spam from reaching their destination. Naïve Bayesian algorithm is one of the most effective approaches used in filtering techniques. The computational power of smart phones are increasing, making increasingly possible to perform spam filtering at these devices as a mobile agent application, leading to better personalization and effectiveness. The challenge of filtering SMS spam is that the short messages often consist of few words composed of abbreviations and idioms. In this paper, we propose an anti-spam technique based on Artificial Immune System (AIS) for filtering SMS spam messages. The proposed technique utilizes a set of some features that can be used as inputs to spam detection model. The idea is to classi...
Investigating the convergence of methods for optimal path selection in computer networks
A genetic and simulated annealing based algorithms for solving the flow assignment problem in computer networks
Selecting the routes and the assignment of link flow in a computer communication networks are ext... more Selecting the routes and the assignment of link flow in a computer communication networks are extremely complex combinatorial optimization problems. Metaheuristics, such as genetic or simulated annealing algorithms, are widely applicable heuristic optimization strategies that have shown encouraging results for a large number of difficult combinatorial optimization problems. This paper considers the route selection and hence the flow assignment problem. A genetic algorithm and simulated annealing algorithm are used to solve this problem. A new hybrid algorithm combining the genetic with the simulated annealing algorithm is introduced. A modification of the genetic algorithm is also introduced. Computational experiments with sample networks are reported. The results show that the proposed modified genetic algorithm is efficient in finding good solutions of the flow assignment problem compared with other techniques.
Untersuchung des Konvergenzverhaltens von Verfahren für die optimale Wegewahl in Rechnernetzen /
ABSTRACT Bremen, Universiẗat, Diss., 1997.
An Efficient Genetic Algorithm Based Clonal Selection and Hill Climbing for Solving QoS Multicast Routing Problem
Quality of Service (QoS) multicast routing is essential for many network applications such as IPT... more Quality of Service (QoS) multicast routing is essential for many network applications such as IPTV, Internet radio, multimedia broadcasting, and real-time telecommunication. Multicast routing involves transport of information from one single sender to multiple destinations. There are two requirements of multicast routing in many multimedia real time applications: one is optimized network cost and other is bandwidth, bounded delay constraints. In this paper an efficient genetic algorithm based on clonal selection and hill climbing is proposed to solve the leastcost multicast routing problem with bandwidth and end-to-end delay constraints. The performance and efficiency of the proposed algorithm have been evaluated by a comparison with other existing genetic algorithms. The simulation results show that the proposed algorithm has high speed convergence and effective in solving the considered problem.
Performance Evaluation of some Routing Protocols using TCP Traffic Types in Mobile Ad Hoc Networks
Routing is a critical issue in a Mobile Ad-hoc Network (MANET). The most famous MANET routing pro... more Routing is a critical issue in a Mobile Ad-hoc Network (MANET). The most famous MANET routing protocols are AODV, DSDV, DSR and AOMDV. Although the performance evaluation of these routing protocols have been extensively simulated, most of the researchers are focusing on the User Datagram Protocol (UDP) traffic type supposing that the Transmission Control Protocol (TCP) sources offers a conforming load to the network. Despite of this, most Internet applications are carried out through TCP. In this paper, we investigate the performance of AODV, DSDV, DSR and AOMDV routing protocols using TCP traffic types such as TCPReno, TCP-Newreno, TCP-Vegas and TCP-Sack. The performance analysis is done in terms of packet delivery ratio, average end to end delay and average throughput using the NS2 simulator. The simulation results show that TCP-Vegas performs better compared with others in the case of end-to-end delay, and has higher packet delivery ratio. The TCP-Reno has higher throughput in th...
Detection and Characterization of Fake Accounts on the Pinterest Social Network
ABSTRACT 1. ABSTRACT Since the beginning of Online Social Networks (OSN) they have played a main ... more ABSTRACT 1. ABSTRACT Since the beginning of Online Social Networks (OSN) they have played a main role in the way people pursue they social life. Almost everyone's social life has become associated with social networks, building your own community and keeping in contact with friends has not been easier and enjoyable. Some OSNs did not survive for long, while others manage to stand still. With the rapid growth of any OSN, and as they rise in popularity, many problems also arise, like online impersonation, fake accounts, and spam. Pinterest, the new member of the OSN family, has become a star in almost no time. As Pinterest gains that much publicity among users, spammers have found their way to it too. In this paper, we try to take a closer look on spammers' activity on Pinterest, trying to make a good understanding of how they operate and how they target end users. Using our analysis we were able to build a detection system and ran it over our Dataset of real user accounts from Pinterest, our system were able to distinguish between fake accounts and legitimate user accounts. The true positive rate of our system exceeds 90% while the false positive rate was 0%. 2. 3. INTRODUCTION Pinterest, the new member of the Online Social Networks family, has become a star in almost no time. It is considered the fastest growing Social Network, as a report from ComeScore (Perez, 2012a) indicated, in this report Pinterest growth was calculated using both unique visitors and clicks from search engines, and it was found to be the fastest growing network in both categories, showing +4377% growth between May 2011 and May 2012, compared to a growth rate for Twitter by 58%, LinkedIn 67%, Tumblr 168%, and Facebook 4% during the same period of time. Moreover, Pinterest users were found to spend more time, buy more items and conduct more transactions online than other social media buyers. Pinterest rapid growth has been the hot topic among users, reviewers, and reporters such as (Collins, shows that the percentage of internet users using Pinterest is nearly the same as for those using Twitter. As the popularity of Pinterest grows, so do the spammers' traffic to it. And hence, many articles have shed the light on the spam problem in Pinterest. In a blog post in April 13 2012,
A Study of Content based Spam Filtering Techniques
E-Learning is efficient, task relevant and just-in-time learning grown from the learning requirem... more E-Learning is efficient, task relevant and just-in-time learning grown from the learning requirements of the new, dynamically changing, distributed business world. The term Semantic Web encompasses efforts to build a new WWW architecture that enhances content with formal semantics, which enables better possibilities for navigating through the cyberspace and accessing its contents.Semantic Web is a product of Web 2.0 (second generation of web) that is supported with automated semantic agents for processing user data to help the user on ease of use and personalization of services. The paper describes a framework for the implementation of an e-learning system based on the Semantic Web, using desktop c# application, data visualization tools, HTML web page parser, RDF generating tools, and SPARQL RDF query language. Hopefully we have elucidated the enormous potential of making web content machine-understandable.
Over the last few years, Online Social Networks (OSN) have become one major way for millions of u... more Over the last few years, Online Social Networks (OSN) have become one major way for millions of users to interact and communicate with each other. OSNs had a deep impact in changing the way people practice their social life partially and replacing some conventional ways people use to keep in touch with family and friends. In 2010 a new member has joined the OSN World, this new member is Pinterest. Pinterest has experienced exponential growth since its birth date. Among all Social Networks, the fastest growing one in 2012 was by far Pinterest. As spammers usually go where users go, it is not surprising that Pinterest is increasingly attracting both users and spammers. Spam on Pinterest has been the hot topic this past year among users, reviewers, and reporters. Although the spam problem in OSNs has been studied before for many networks such as Facebook and Twitter, we mark this paper to be the first review to spot the problem of spam and fake accounts in Pinterest. In this paper, we take a closer look on spammers' activity on Pinterest, trying to make a good understanding of how they operate and how they target end users.
Improving the Efficiency of the Flow Deviation Method for Solving the Optimal Routing Problem in a Packet-Switched Computer Networks
An Efficient Three-phase Email Spam Filtering Technique
British Journal of Mathematics & Computer Science, 2014
UML class diagram metrics tool
2009 International Conference on Computer Engineering & Systems, 2009
... Tarek. M. Mahmoud is with the Department of Computer Science, Faculty of Science, Minia Unive... more ... Tarek. M. Mahmoud is with the Department of Computer Science, Faculty of Science, Minia University, El-Minia, Egypt (e-mail: [email protected]). ... 350-359, Los Alamitos CA, IEEE Computer Society Press, 2004. [27] Thierry Miceli, Houari A. Sahraoui, and Robert Godin. ...
International Journal of Computer Applications, 2015
Mobile ad hoc networks (MANETs) are composed of a set of stations (nodes) communicating through w... more Mobile ad hoc networks (MANETs) are composed of a set of stations (nodes) communicating through wireless channels, without any fixed backbone support in which nodes are allowed to join and leave the network at any point of time. MANETs are generally more vulnerable to information and physical security threats than wired networks, so security is an essential requirement in MANETs to provide secured communication between mobile nodes. One of the most common attacks against routing in MANETs is the Black Hole attack. A black hole is a malicious node uses the routing protocol to advertise itself as having the shortest path to the node whose packets it wants to intercept. In this paper, we attempt to focus on improving the security of one of the popular routing protocol for MANETS, namely the Ad hoc On Demand Distance Vector (AODV) routing protocol to avoid black hole attacks. The proposed Intrusion Avoidance System (IASAODV) can be considered as modification of the AODV protocol and can be used to detect and avoid the black hole attack. The conducted experimental results using Network Simulator NS-2.35 show an improvement in Packet Delivery Ratio (PDR), Normalized Routing Load (NRL) and throughput using the proposed protocol compared with AODV routing Protocol in the case of existing black hole attack.
Routing and Capacity Assignment Problem in Computer Networks Using Genetic Algorithm
Information Sciences Letters, 2013
ABSTRACT In large-scale computer communication networks (e.g. the nowadays Internet), the assignm... more ABSTRACT In large-scale computer communication networks (e.g. the nowadays Internet), the assignment of link capacity and the selection of routes are extremely complex network optimization problems. Efficient solutions to these problems are much sought after because such solutions could lead to considerable monetary savings and better utilization of the networks. Unfortunately, as indicated by much prior theoretical research, these problems belong to the class of nonlinear combinatorial optimization problems, which are mostly (if not all) NP-hard problems. Metaheuristics, such as genetic and simulated annealing algorithms, are widely applicable heuristic optimization strategies that have shown encouraging results for a large number of difficult combinatorial optimization problems. In this paper, we propose three different approaches for solving the routing and capacity assignment (RCA) problem. The first approach uses a GA. The second approach uses the SA algorithm. The last approach combines the GA with the SA to improve the performance of the GA. The paper also presents the experiments that we have conducted to evaluate the effectiveness of the proposed approaches compared to a one of the heuristic algorithms for solving the same problem. The results show that the hybrid approach is more efficient in finding good solutions to the RCA problem compared to other techniques.
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