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Transmission control protocol (TCP) was originally designed for fixed networks to provide the reliability of the data delivery. The improvement of TCP performance was also achieved with different types of networks with introduction of new TCP variants. However, there are still many factors that affect performance of TCP. Mobility is one of the major affects on TCP performance in wireless networks and MANET (Mobile Ad Hoc Network). To determine the best TCP variant from mobility point of view, we simulate some TCP variants in real life scenario. This paper addresses the performance of TCP variants such as TCP-Tahoe, TCP-Reno, TCP-New Reno, TCPVegas,TCP-SACK and TCP-Westwood from mobility point of view.The scenarios presented in this paper are supported by Zone routing Protocol (ZRP) with integration of random waypoint mobility model in MANET area. The scenario shows the speed of walking person to a vehicle and suited particularly for mountainous and deserted areas. On the basis of simulation, we analyze Round trip time (RTT) fairness, End-to-End delay, control overhead, number of broken links during the delivery of data. Finally analyzed parameters help to find out the best TCP variant., Comment: 09 pages, 09 pages, In proceedings of international conference on 2011 ASEE Northeast Section Conference, At University of Hartford, Connecticut, USA

Emergence of latest technologies has diverted the focus of people form Computer-Supported Collaborative Learning (CSCL) to mobile supported collaborative learning. MCL is highly demanded in educational organizations to substantiate the pedagogical activities. Some of the MCL supportive architectures including applications are introduced in several fields to improve the activities of those organizations, but they need more concise paradigm to support both types of collaboration: synchronous and asynchronous. This paper introduces the new preusability testing method that provides educational support and gives complete picture for developing new pedagogical group application for MCL. The feature of application includes asynchronous and synchronous collaboration support. To validate the features of application, we conduct the post usability testing and heuristic evaluation, which helps in collecting the empirical data to prove the effectiveness and suitability of Group application. Further, application aims to improve learning impact and educate people at anytime and anywhere., Comment: 8 pages, 5 figures, ICGST-AIML Journal, Volume 12, Issue 1, July 2012

WSNs are becoming an appealing research area due to their several application domains. The performance of WSNs depends on the topology of sensors and their ability to adapt to changes in the network. Sensor nodes are often resource constrained by their limited power, less communication distance capacity, and restricted sensing capability. Therefore, they need to cooperate with each other to accomplish a specific task. Thus, clustering enables sensor nodes to communicate through the cluster head node for continuous communication process. In this paper, we introduce a dynamic cluster head election mechanism. Each node in the cluster calculates its residual energy value to determine its candidacy to become the Cluster Head Node (CHN). With this mechanism, each sensor node compares its residual energy level to other nodes in the same cluster. Depending on the residual energy level the sensor node acts as the next cluster head. Evaluation of the dynamic CHN election mechanism is conducted using network simulator-2 (ns2). The simulation results demonstrate that the proposed approach prolongs the network lifetime and balancing the energy, Comment: 5 pages, 2 figures, In proceedings of 29th International Conference on Computers and Their Applications (CATA 2014), Las Vegas, Nevada, USA,24-26 March 2014

Due to rapid advancement in modern technology, as one of the major concerns is the stability of business. The organizations depend on their systems to provide robust and faster processing of information for their operations. Efficient data centers are key sources to handle these operations. If the organizational system is not fully functional, the performance of organization may be impaired or clogged completely. With the developments of real-time applications into data centers for data communications, there is a need to use an alternative of the standard TCP protocol to provide reliable data transfer. Stream Control Transmission Protocol (SCTP) consists of several well built-in characteristics that make it capable to work efficiently with real-time applications. In this paper, we evaluate an optimized version of STCP. The optimized version of SCTP is tested against a non optimized version of STCP and TCP in a data center environment. Simulations of the protocols are carried using NS2 simulator, Comment: 05 PAGES AND 08 FIGURES

With developments of real-time applications into data centers, the need for alternatives of the standard TCP protocol has been prime demand in several applications of data centers. The several alternatives of TCP protocol has been proposed but SCTP has edge due to its several well-built characteristics that make it capable to work efficiently. In this paper, we examine the features of SCTP into data centers like Multi-streaming and Multi-homing over the features of TCP protocol. In this paper, our objective is to introduce internal problems of data centers. Robust transport protocol reduces the problems with some extend. Focusing the problems of data centers, we also examine weakness of highly deployed standard TCP, and evaluate the performance of SCTP in context of faster communication for data centers. We also discover some weaknesses and shortcomings of SCTP into data centers and try to propose some ways to avoid them by maintaining SCTP native features. To validate strength and weakness of TCP and SCTP, we use ns2 for simulation in context of data center. On basis of findings, we highlight major strength of SCTP. At the end, we Implemen, Comment: 08 Page, 10 Figures

The revolution of wireless sensors networks (WSNs) has highly augmented the expectations of people to get the work done efficiently, but there is little bit impediment to deal with deployed nodes in WSNs. The nature of used routing and medium access control (MAC) protocols in WSNs is completely different from wireless adhoc network protocols. Sensor nodes do not have enough capability to synchronize with robust way, in resulting causes of longer delay and waste of energy. In this paper, we deploy efficientenergy consuming sensors and to find one hop robust and efficient destination search in WSNs. We firstly deploy BT (Bluetooth enabled) sensors, which offer passive and active sensing capability to save energy. This work is a continuation of previous published work in [2]. The BT node is supported with efficient searchmethodss. The main objective of this contribution is to control different types of objects from remote places using cellular phone. To validate our proposed methodology,simulation is done with network simulator (ns2) to examine the behavior of WSNs. Based on simulation results, we claim that our approach saves 62% energy spent for finding best one- hop destination as compared with existing techniques.

We deploy BT node (sensor) that offers passive and active sensing capability to save energy. BT node works in passive mode for outdoor communication and active for indoor communication. The BT node is supported with novel automatic energy saving (AES) mathematical model to decide either modes. It provides robust and faster communication with less energy consumption. To validate this approach, network simulator-2 (ns2) simulation is used to simulate the behavior of network with the supporting mathematical model. The main objective of this research is to remotely access different types of servers, laptops, desktops and other static and moving objects. This prototype is initially deployed to control MSCS [13] & [14] from remote place through mobile devices. The prototype can further be enhanced to handle several objects simultaneously consuming less energy and resources., Comment: 11 pages, 7 figures, International Journal of computers and technology 2013

Mobile collaborative learning (MCL) is extensively recognized field all over the world. It demonstrates the cerebral approach combining the several technology to handle the problem of learning. MCL motivates the social and educational activities for creating healthier environment. To advance and promote the baseline of MCL, different frameworks have been introduced for MCL. From other side, there is no highly acceptable security mechanism has been implemented to protect MCL environment. This paper introduces the issue of rogue DHCP server, which highly affects the performance of users who communicate with each other through MCL. The rogue DHCP is unofficial server that gives incorrect IP address to user in order to use the legal sources of different servers by sniffing the traffic. The contribution focuses to maintain the privacy of users and enhances the confidentiality. The paper introduces multi-frame signature-cum anomaly-based intrusion detection systems (MSAIDS) supported with innovative algorithms, modification in the existing rules of IDS and use of mathematical model. The major objectives of research are to identify the malicious attacks created by rogue DHCP server. This innovative mechanism emphasizes the security for users in order to communicate freely. It also protects network from illegitimate involvement of intruders. Finally, the paper validates the mechanism using three types of simulations: testbed, discrete simulation in C++ and ns2. On the basis of findings, the efficiency of proposed mechanism has been compared with other well-known techniques., Comment: 13 pages, 13 figuers. arXiv admin note: substantial text overlap with arXiv:1208.2073, arXiv:1210.2030

The rogue DHCP is unauthorized server that releases the incorrect IP address to users and sniffs the traffic illegally. The contribution specially provides privacy to users and enhances the security aspects of mobile supported collaborative framework (MSCF) explained in [24].The paper introduces multi-frame signature-cum anomaly-based intrusion detection systems (MSAIDS) supported with novel algorithms and inclusion of new rules in existing IDS. The major target of contribution is to detect the malicious attacks and blocks the illegal activities of rogue DHCP server. This innovative security mechanism reinforces the confidence of users, protects network from illicit intervention and restore the privacy of users. Finally, the paper validates the idea through simulation and compares the findings with known existing techniques., Comment: 20 pages, 9 figures International Journal of E -Technology Volume 3 Number 2 May 2012. arXiv admin note: substantial text overlap with arXiv:1208.2073

Transmission control protocol (TCP) is a connection oriented protocol for several types of distributed applications. TCP is reliable particularly for traditional fixed networks. With emergence of faster wireless networks, TCP has been performing poorly in its original format. The performance of TCP is affected due to assorted factors including congestion window, maximum packet size, retry limit, recovery mechanism, backup mechanism and mobility. To overcome deficiency of original TCP, Several modifications have been introduced to improve network quality. The mobility is a major hurdle in degrading the performance of mobile wireless networks. In this paper, we introduce and implement new TCP variant University of Bridgeport (UB) that combines the features of TCP Westwood and Vegas. We examine the performance of TCP-UB, Vegas and Westwood using different realistic scenarios. NS2 simulator demonstrates the stability of TCP-UB as compared with TCP Vegas and Westwood in highly congested networks from the mobility point of view., Comment: 13 Pages, 11 figures

Latest study shows that MCL is highly focusing paradigm for research particularity in distance and online education. MCL provides some features and functionalities for all participants to obtain the knowledge. Deployment of new emerging technologies and fast growing trends toward MCL boom attract people to develop learning management system, virtual learning environment and conference system with support of MCL. All these environments lack the most promising supportive framework. In addition some of major challenges in open, large scale, dynamic and heterogeneous environments are not still handled in developing MCL for education and other organizations. These issues includes such as knowledge sharing, faster delivery of contents, request for modified contents, complete access to enterprise data warehouse, delivery of large rich multimedia contents (video-on-demand), asynchronous collaboration, synchronous collaboration, support for multi model, provision for archive updating, user friendly interface, middleware support and virtual support. To overcome these issues; the paper introduces novel framework for MCL consisting of four layers with many promising functional components, which provide access to users for obtaining required contents from enterprise data warehouse (EDW). Novel framework provides information regarding the course materials, easy access to check the grades and use of labs. The applications running on this framework give substantial feedback for collaboration such as exchange for delivery of communication contents including platform for group discussion, short message service (SMS), emails, audio, video and video-on-demand to obtain on-line information to students and other persons who will be part of collaboration., Comment: 8 pages, 5 figure IADIS International Conference on Internet Technologies & Society 2011

Deployment of emerging technologies and rapid change in industries has created a lot of risk for initiating the new projects. Many techniques and suggestions have been introduced but still lack the gap from various prospective. This paper proposes a reliable project scheduling approach. The objectives of project scheduling approach are to focus on critical chain schedule and risk management. Several risks and reservations exist in projects. These critical reservations may not only foil the projects to be finished within time limit and budget, but also degrades the quality, and operational process. In the proposed approach, the potential risks of project are critically analyzed. To overcome these potential risks, fuzzy failure mode and effect analysis (FMEA) is introduced. In addition, several affects of each risk against each activity are evaluated. We use Monte Carlo simulation that helps to calculate the total time of project. Our approach helps to control risk mitigation that is determined using event tree analysis and fault tree analysis. We also implement distribute critical chain schedule for reliable scheduling that makes the project to be implemented within defined plan and schedule. Finally, adaptive procedure with density (APD) is deployed to get reasonable feeding buffer time and project buffer time., Comment: 10 pages, 5 figures (International Journal of Business and Social Science)

Maintaining the quality of service (QOS) and controlling the network congestion are quite complicated tasks. They cause degrading the performance of the network, and disturbing the continuous communication process. To overcome these issues, one step towards this dilemma has been taken in form of Pre-congestion notification (PCN) technique. PCN uses a packet marking technique within a PCN domain over IP networks. It is notified by egress node that works as guard at entry point of network. Egress node gives feedback to communicating servers whether rate on the link is exceeded than configured admissible threshold or within the limit. Based on this feedback, admission decisions are taken to determine whether to allow/block new coming flows or terminate already accepted. The actual question is about selection of right algorithm for PCN domain. In this paper, we investigate the analytical behavior of some known PCN algorithms. We make slide modifications in originality of PCN algorithms without disquieting working process in order to employ those within similar types of scenarios. Our goal is to simulate them either in highly congested or less congested realistic scenarios. On the basis of simulation done in ns2, we are able to recommend each PCN algorithm for specific conditions. Finally, we develop a benchmark that helps researchers and scientific communities to pick the right algorithm. Furthermore, the benchmark is designed to achieve specific objectives according to the users' requirements without congesting the network., Comment: 16 Pages, 16 figures; International Journal of Computer Networks & Communications (IJCNC) July 2012, Volume 4, Number 4

Mobile collaborative learning (MCL) is highly acknowledged and focusing paradigm in eductional institutions and several organizations across the world. It exhibits intellectual synergy of various combined minds to handle the problem and stimulate the social activity of mutual understanding. To improve and foster the baseline of MCL, several supporting architectures, frameworks including number of the mobile applications have been introduced. Limited research was reported that particularly focuses to enhance the security of those pardigms and provide secure MCL to users. The paper handles the issue of rogue DHCP server that affects and disrupts the network resources during the MCL. The rogue DHCP is unauthorized server that releases the incorrect IP address to users and sniffs the traffic illegally. The contribution specially provides the privacy to users and enhances the security aspects of mobile supported collaborative framework (MSCF). The paper introduces multi-frame signature-cum anomaly-based intrusion detection systems (MSAIDS) supported with novel algorithms through addition of new rules in IDS and mathematcal model. The major target of contribution is to detect the malicious attacks and blocks the illegal activities of rogue DHCP server. This innovative security mechanism reinforces the confidence of users, protects network from illicit intervention and restore the privacy of users. Finally, the paper validates the idea through simulation and compares the findings with other existing techniques., Comment: 20 pages and 11 figures; International Journal of Computer Networks and Communications (IJCNC) July 2012, Volume 4. Number 4