INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 01, JANUARY 2016 ISSN 2277-8616 153 IJSTR©2016 www.ijstr.org Investigating And Evaluating Of Network Failures And Performance Over Distributed WAN In Application Protocol Layer Enoch Okoh Kofi, Micheal Asante, Francis Kwadzo Agbenyegah Abstract: The Experiment was done to find out network failures and application performance relationship over distributed Wide Area Net (WAN). In order to access related application over the cloud there must be an internet connectivity which will help the respective workstations to access the remote server for applications being deployed over the network. Bandwidth improvement helps in reducing utilization over the network and it also helps in improving Application Efficiency of these Applications in terms of Response Time. Routers were configured under Enhance Interior Gateway Routing Protocol (EIGRP) to reduce utilization and to ensure load sharing over the network. Three scenarios were modeled and their performance efficiency was evaluated. A modeled computer Network with and without a fail Router under different scenarios and such Network was simulated with emphasis on the Application Performance. The Experiment was done for fifty workstations under three scenarios and these three scenarios were accessed and evaluated on experimental basis using Riverbed modeler to show the Effect of Application Network performance. The performance results show that increasing the bandwidth reduces utilization and also with the failure of one communication bandwidth, users can still access Network Application with a minimal cost. Index Terms: Wide Area Network, Enhance Interior Gateway Routing Protocol (EIGRP), Routers, Riverbed Modeler, Utilization ———————————————————— 1 INTRODUCTION Network performance has been one of the key indicators that determined the quality of Service a vendor or an agency is rendering to its customers or the way and manner the network delivers based on the arrival of packet and other related components. Users of the said network complains more frequently about the efficiency of the network when it is not delivering the expected preambles to the masses, the masses would want to know why the said network is underperforming and hence this has called for the study to see how the network could be optimized to boost its performance in ensuring that quality of service is at its best. With high amount of data that are being injected into the network for service delivery has been the cause of a dwindling network hence the use of Riverbed modeler simulator to model and study the performance of a model network by measuring the key performance indicators based on traffic variation with respect to user behavior. To measure network performance quantitatively, several related aspect of the network are considered before drawing on any conclusions and such area would have to be studied for a period of time. Network application such as File transfer protocol(FTP), Hypertext transfer protocol(HTTP),Telnet, voice runs through the network and exponentially increase the packet injected into the network and these could result in high probability blocking congestion, etc. In field of computer science network performance comprises of the aspect of response time, loss, signal-to-noise Ratio. [11] In a high optimized network, the traffic pattern must be modeled in a way that will result in resource reservation and control certain parametric indicators to provide different priority to different application users. 2 NETWORK APPLICATION Network Application is part of network protocols in the sense that they exchange messages with their peer on other machine of interest. [22] Differentiated Application services are deploying to the network in order to ensure that their service content would be available for the respective user. Database Application, Browser and File sharing application are part of network application that utilizes internet and other hardware platform to perform useful function and network application is based on the general phrase that is designed by expert to help setup, manage and monitor the computer networks. 3 RESEARCH PROBLEM The world has come to an era where a major industrial player relies so much on Digital transmission which is done through computers and telecommunication networks. The Emergence of the Global Economy is only possible through a highly optimized network put in place to ensure high Quality of Service. To become a Global market leader in this Global Economy, we must strive for excellence so that we can become versatile in whatever activities we engage ourselves in making sure that we are seen everywhere and this is only possible through digital transmission which involves network of computers for the purposes of transmitting Information through multiplicity of channel allocation. Network performance is critical to the success of a business operation and because of these it is always imperative to look into fine tuning of the network system in ensuring that it gives it best at all times. 4 RELATED WORK Data Network is a telecommunication system which allows computers and other wireless systems to exchange data during transmission and most of the connections are established either by cable media or wireless media by the Respective Nodes within the circuit. The performance of such network must consistently be monitored in ensuring a very good indicator in satisfying the customer within the block. In pursuing the task of good performance, certain part of the network must be fine- tuned to meet the desire standard of the needed quality of service. The critical component in managing information effectively is by network optimization. Information technology is growing at an alarming rate with more and more application consuming a greater amount of bandwidth as well as producing larger volumes of Data from application of which majority of these data has to flow through corporate networks. These ad hoc growths add to the stress of already over stress network