Energy Efficient Location Aided Routing Protocol for Wireless MANETs

A Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network without using any centralized access point, infrastructure, or centralized administration. In this paper we introduce an Energy Efficient Location Aided Routing (EELAR) Protocol for MANETs that is based on the Location Aided Routing (LAR). EELAR makes significant reduction in the energy consumption of the mobile nodes batteries by limiting the area of discovering a new route to a smaller zone. Thus, control packets overhead is significantly reduced. In EELAR a reference wireless base station is used and the network's circular area centered at the base station is divided into six equal sub-areas. At route discovery instead of flooding control packets to the whole network area, they are flooded to only the sub-area of the destination mobile node. The base station stores locations of the mobile nodes in a position table. To show the efficiency of the proposed protocol we present simulations using NS-2. Simulation results show that EELAR protocol makes an improvement in control packet overhead and delivery ratio compared to AODV, LAR, and DSR protocols.Comment: 9 Pages IEEE format, International Journal of Computer Science and Information Security, IJCSIS 2009, ISSN 1947 5500, Impact factor 0.423, http://sites.google.com/site/ijcsis

PIPELINED DATA PARALLEL MODEL OF ADVANCED ENCRYPTION STANDARD ALGORITHM

The Advanced Encryption Standard (AES) was officially adopted in 2002 as the new encryption standard algorithm. AES specifies a FIPS-approved cryptographic algorithm that can be used to protect electronic data. It is a symmetric block cipher that can encrypt and decrypt information. This paper develops a pipelined data parallel model of AES. The parallelism in the algorithm is two dimensional. The first dimension is AES enter-stage (pipelining) and the second dimension is data parallelism. Pipelining parallelism exploits the availability of several processes to execute different stages of different data blocks in parallel. The data parallelism exploits data independence among data blocks to implement data level parallelism. The parallel implementation of AES decreases the time needed for encryption and decryption processes. We use the ECB mode in encryption/decryption algorithm in our parallel implementation of AES to implement the parallelization at data level where data blocks are encrypted and decrypted in parallel. We also develop an MPI-based algorithm to be used with a cluster of workstations (COW). We validate the approach by simulating the model with various input parameters (input data file size, number of processes, communication/computation operation execution time, etc.) and measuring the corresponding performance. Performance metrics include speedup, communication to computation ratio and efficiency. Results show that performance obtained by the developed model is superior to parallel implementations of AES which include only data parallelism or pipelining

Cryptography Using Quasi Group and Chaotic Maps

In this paper a symmetric key (stream cipher mode/block cipher mode) cryptosystem is proposed, involving chaotic maps and quasi group. The proposed cryptosystem destroys any existing patterns in the input, and also, it maximizes entropy. Moreover, the n-grams illustrate that the proposed cryptosystem is secure against the statistics analysis. Furthermore, Experimental results show that the ciphertext has good diffusion and confusion properties with respect to the plaintext and the key, also the results demonstrate that the block cipher mode gives higher entropy than the steam cipher mode

SOMvisua: Data Clustering and Visualization Based on SOM and GHSOM

Text in web pages is based on expert opinion of a large number of people including the views of authors. These views are based on cultural or community aspects, which make extracting information from text very difficult. Search in text usually finds text similarities between paragraphs in documents. This paper proposes a framework for data clustering and visualization called SOMvisua. SOMvisua is based on a graph representation of data input for Self-Organizing Map (SOM) and Growing Hierarchically Self-Organizing Map (GHSOM) algorithms. In SOMvisua, sentences from an input article are represented as graph model instead of vector space model. SOM and GHSOM clustering algorithms construct knowledge from this article

NetworkMonitoring System (NMS)

Due to rapid changes and consequent new threats to computer networks there is a need for the design of systems that enhance network security. These systems make network administrators fully aware of the potential vulnerability of their networks. This paperdesigns a Network Monitoring System (NMS) which is an active defense and complex network surveillance platform designed for ISPs to meet their most rigorous security requirements. This system is motivated by the great needof government agencies, ecommerce companies and Web development organizations to secure their computer networks. The proposed system is also used by network administrators to enable them understand the vulnerabilities affecting computer networks. This enables these administrators to improve network security. The proposed system is a lawful network traffic (Internet Service Provider IP trffic) interception system with the main task of obtaining network communications, giving access to intercepted traffic to lawful authorities for the purpose of data analysis and/or evidence. Such data generally consist of signaling, network management information, or the content of network communications. The intercepted IP traffic is gathered and analyzed for network vulnerability in real time. Then, the corresponding TCP/UDP traffic (Web page, email message, VOIP calls, DHCP traffic, files transferred over the LAN such as HTML files, images, and video files, etc.) is rebuilt and displayed. Based on the results of the analysis of the rebuilt TCP/UDP an alarm could be generatedif amalicious behavior is detected. Experimental results show that the proposed system has many

PAWS: A performance evaluation tool for parallel computing systems

A description is given of PAWS (parallel assessment window system), a set of tools that provides an interactive user-friendly environment for analysis of existing, prototype, and conceptual machine architectures running a common application. PAWS consists of an application tool, an architectural characterization tool, a performance assessment tool, and an interactive graphical display tool. The application characterization tool provides a facility for evaluating the level and degree of an application's parallelism. The architecture characterization tool allows users to create, store, and retrieve descriptions of machines in a database. This approach permits users to evaluate conceptual machines before building any hardware. The performance assessment tool generates profile plots through the interactive graphical display tool. It shows both the ideal parallelism inherent in the machine-independent dataflow graph and

A Hybrid Localization Protocol for Mobile Sensor Networks

Many localization techniques and protocols have been proposed for wireless sensor networks. However, few of these techniques consider the mobility of the networked sensors. When sensors are mobile, localization must be invoked periodically to enable sensors to track their location. Localizing should be made frequently to allow the sensors to track their location accurately. However, localizing frequently is expensive in terms of energy consumption and program time. This research proposes an efficient Hybrid Localization Protocol (HLP) for mobile sensor networks that dynamically invokes adaptive and predictive protocols based on some heuristics. The proposed HLP determines the optimal localization frequency based on the sensor's speed and mobility pattern predictability. Optimal localization frequency reduces the energy consumption of localization while increasing the localization accuracy. Experimental simulation results and analysis show that the proposed protocol is more efficient in terms of energy consumption and localization accuracy than the existing counterpart protocols

Optimal TCP and Queuing Discipline for Web Proxy Servers

Web proxies are a fundamental component in networks. They are used to cache and accelerate Web access and to save the bandwidth and traffic volume across the Internet. The performance of Web proxies is proven to be very vital and crucial in determining the overall usage and throughput of the Internet links. This paper investigates the effect of TCP various implementations and queuing disciplines for different loads on Web proxy servers through simulation using ns-2 simulator. The evaluated TCP models are Tahoe (referred to as TCP), Reno, New Reno, Vegas, and Sack. The evaluated queuing disciplines are Drop Tail, SFQ, DRR, and RED. The network topology used in the evaluation process is a realistic mapping of a typical Web proxy configuration in an enterprise network. The Web proxy lies in the middle between the router that connects the internal network segments and the external router that connects

Synchronizing Moodle and University Enrollment Databases, A Case Study: Islamic University of Gaza

Moodle is a learning management system that is used in universities to support the educational process. Moodle provides many collaborative tools and interfaces that allow instructors to communicate with their students and manage their courses. Moodle maintains its own database in which courses and students accounts are created. In addition, the admission deaneries in universities maintain databases to manage the traditional educational process. In this paper, an application-oriented research has been conducted to synchronize the university admission database and the Moodle database. The synchronization process eliminates the overhead of creating the courses and students accounts in the Moodle database by transferring them automatically from the admission database. Experimental results show the validity and correctness of the proposed methodology