Rajan Vohra

WLAN Performance Improvisation by Fine Tuning IEEE 802. 11 Parameters

Wireless networks has biggest constraint of limited bandwidth in comparison to wired networks but in spite of this constraint wireless networks are becoming popular day by day on account of their flexibility, mobility as well as inexpensive physical medium (air). Wireless local area networks (WLANs) are error-prone as well as fragile. The commuters feel annoyed when all of sudden communication cuts off and transmission of packets fails. Hence, it becomes an obligation to improve WLAN performance metrics. We investigated throughput and delay performance of WLANs using network simulation tool OPNET concentrating on the IEEE 802.11 Mac layer parameters, and suggest that Wireless LAN performance can be improved by fine tuning parameters such as fragmentation threshold, request to send (RTS) thresholds and buffer size. The main objective of this paper is buffer size manipulation to reduce load and delays, leading to performance improvement.

MANET Link Performance Parameters using Ant Colony Optimization Approach

to-end delay of routing packets from the source to destination in a Mobile ad-hoc network is a major challenge for a large number of network scientists. This paper presents a new routing approach for mobile ad hoc networks (MANETs) which takes into consideration the Ant Colony Optimization (ACO) technique in conjunction with linear programming approach for minimizing the overall delay in networking environment. Ant colony optimization algorithms have all been inspired by a specific foraging behavior of colonies of the ants, which are able to explore the optimum route connecting the colonys nest with a source of food. It has been observed that the mean end-to-end delay of a link from the source to the destination is one of the most important metric for a MANET. The other metrics that have been considered and evaluated are utilization or efficiency of link, arrival rate and service rate with respect to link delay. The simulation tool used for our model is MATLAB 7.5.

Metrics improvement of MANET using reactive protocols approach

Mobile ad hoc networks (MANETs) are a collection of wireless nodes that dynamically create a wireless network among themselves without any infrastructure. Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. The objective of this paper is to evaluate the simulation of MANET reactive routing protocols that are Ad Hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) and temporally ordered routing algorithm (TORA) for Guru Nanak Dev University Campus environment using the High Resolution Video Conferencing application. Comparative analysis has been carried out based on the results obtained by simulations with OFDM (802.11a) and Extended Rate PHY (802.11g) physical characteristics in OPNET Modeler version 14.5. Parameters used are Throughput, End to End delay, Routing load and Media Access Delay.

Physical Characteristics based MANET Routing Protocols for Campus Network

Mobile ad-hoc networks (MANETs) consist of mobile devices that rely on wireless media for bilateral communication. These can be set up anywhere and at any time because these require neither infrastructure nor central administration. This paper concentrates on the comparative performance evaluation of three reactive routing protocols Ad Hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Temporally Ordered Routing Algorithm (TORA) for the three different Physical Characteristics namely Direct Sequence, Frequency Hopping and Infra Red in campus network of Guru Nanak Dev University, Amritsar using OPNET MODELER version 14.5. The performance metrics used for our simulation are Wireless LAN delay, Retransmission Attempts, Throughput and Media Access Delay.

Multi Hop Routing in Wireless Mobile Networks using Ant Colony Optimization

Quality of Service is an indispensable parameter to evaluate the performance of any network, so research engrosseson valuing some important QoS parameters for mobile Adhoc network using AntHocNet routing algorithm. MATLAB software version R2011b is used for simulations due to its ease of node deployment and network set up. Simulation is done while varying the number of packets sent as 10, 30, 50, 70 and 90in a network scenario. It is analyzed that AntHocNet provides excellent performance for fewer hops 1, 2 and 3 whereas for increased number of hops9 and 10, it reveals from the routing metrics that use of AntHocNet is more advantageous over the other routing protocols like DSDV, AODV, DSR and TORA.The simulation enactment graphs shows better performance in terms of End-to-end delay, Delay jitter and superlative performance in terms of SINR with extended number of hops when the payload on the source node increases.

Assessment of Dynamic Routing Protocols for Increased Number of Workstations

Paper describe the analysis of dynamic routing protocols EIGRP, OSPF and their combination i.e. OSPF-EIGRP for the scenario which have increasing number of workstations from 3 to 50 in steps working on three dissimilar applications (Database, E-mail, and HTTP). Initially three individual workstations were considered which then replaced by LANs of 10, 25 and 50 in order to appraise the recompense of one scenario over the other. Simulation is carried out with the help of Optimized Network Engineering Tool (OPNET) which gives the better edge over the other network simulation tools available. The assessment is based on the two parameters namely E-mail Upload Response Time and HTTP Page Response Time. The results concluded that overall best performance can be achieved with the help of EIGRP protocol for the given scenario.

OPNET based Wireless LAN Performance Improvisation

In order to analyze the performance of Wireless Local Area Networks (WLANs) effectively, it is important to identify those network settings that can cause the networks performance to go from good to poor. Low throughput, high packet loss rate, delayed round trip time (RTT), increased retransmissions, and increased collisions are the detrimental attributes to look for, when poor network performance is encountered. In this paper, our main focus is to analyze and evaluate the role of the media access delay as well as processing delay towards the performance of WLANs. The simulation tool OPNET has been used for finetuning the WLAN parameters and simulation demonstrate that WLAN performance can be enhanced by tuning different metrics such as buffer size, fragmentation threshold and request to send (RTS) thresholds. In this paper, we emphasized on buffer size and its subsequent effect on service quality. By varying the buffer size to a value other than specified in the standards, will reduce WLAN delay, media access delay with minutest changes observed in throughput. General Terms WLAN, OPNET, Video conference KeywordsOPNET, Delay, Throughput, Media Access delay

Relative analysis of AODV & DSDV routing protocols for MANET based on NS2

To design any wireless network, routing and protocol selection are of important consideration. In Mobile Adhoc Networks (MANET), routing protocols should have best throughput with minimum delay. So the performance in critical situations is the main concern of mobile networks. In this paper, wireless network of mobile nodes has been designed with defined parameters and the relative analysis is carried out on Adhoc On-demand Distance Vector (AODV) and Destination Sequenced distance Vector (DSDV) protocols using NS2 simulator. The Throughput of generating and receiving packets, Jitter on sending and receiving side and End to end delay are the common parameters used for the comparison.

Statistical analysis of redundancy based wire-line and wireless networks

Paper investigates that how the performance of the wireless local area networks (WLANs) is effected by the redundancy in a office environment. Environment has been simulated, where many applications are in use at a time and their mutual effects thereof. Here, OPNET has been used to develop a new model suitable for office/company environment. Performance of the WLANs has been evaluated against two types of applications (FTP and DATABASE) for a office/company environment. This model provides us the significant advantage of not having any single point of failure. It has been shown here that there is no degradation of the performance if one of the path has been failed for the communication.