OPNET Simulation Research Articles

Performance and Analysis of Video Streaming of Signals in Wireless Network Transmission

In this work, we describe an effective video communication for wireless transmission of H.264/AVC medical ultrasound video over mobile WiMAX networks. Medical ultrasound is encoded using error resilient encoding in which, the quantization levels are varied according to the function of the diagnostic significance of image region. We explain how our proposed system allows for the transmission of high-resolution clinical video which is being encoded at the clinical acquisition resolution and then decoded with low delay. We perform this functional concept by using OPNET simulations of the mobile WiMAX medium and also considering some of the physical layer characteristics also such as service prioritization classes, different types of modulation being performed, fading channel's conditions, coding schemes and their types and mobility. We are encoding the ultrasound videos at 4CIF (704×576) resolution to provide high level of clarity. The video quality assessment is being done based on both of their evaluations in objective and subjective manner.

Comparison of RIP, EIGRP, OSPF, IGRP Routing Protocols in Wireless Local Area Network (WLAN) by using OPNET Simulator tool - A Practical Approach

In Adhoc Network group communication is more important, in which routing protocols play a vital role for data transmission. With/Without using central server or access point, the Wireless network form a temporary network with collection of wireless nodes in which, each node changes randomly at different times. In order to establish data transmission between nodes, multiple hops are needed because of limited range i.e. transmission rate. In this paper, we have analyzed and simulated a proposed Wireless Local Area Network (WLAN) using different routing protocols. The performances of different protocols are compared and analyzed using Optimum Network Performance (OPNET) simulator tool in which metrics like delay, throughput, packet delivery, load, Ethernet delay, are measured.

Enhanced Quality of Service in Worldwide Interoperability for Microwave Access Networks

The WiMAX system effectively supports wide variety of broadband wireless access technologies, which including high speed internet and multimedia access with high Quality of service (QoS) requirements. Real time services such as VoIP are becoming popular and are major revenue earners for network service providers. However, there are still many challenges that need to be addressed to provide a steady and good quality voice connection over the best effort WiMAX network .To support flexibility, efficiency and various requirements of QoS over a range of different applications and environments several provisioning and mechanisms are provided .This research paper investigates the performance of VoIP traffic over WiMAX networks, the impact of various voice codec schemes and statistical distribution for VoIP over WiMAX has been investigated in detail. Through various simulation experiments under realistic networking scenarios, this study provides an insight into the VoIP performance in the WIMAX networks. The simulations results indicate that better choice of voice codec's and statistical distribution have significant impact on VoIP performance in the WiMAX networks and Performance of selected parameters will be done using the network simulator OPNET

PERFORMANCE EVALUATION OF VARIOUS TYPES OF NODES IN MANET WITH DSR ROUTING PROTOCOLS

Day by day, wireless communication popularity growi ng fast, it has led wireless communication data rat es higher and made its prices cheaper, that’s why wireless communication is growi ng so fast. The latest technological demands now a day’s arising from laptops, wireless devices such as wireless local area networ ks (LANs) etc. In this paper we compared different types of node in MANET like static nodes, dynamic nodes and dynamic nodes with trajectory by using Dynamic routing protocol (DSR) and compared the performance of these nodes by using OPNET simulator 14.5. The performance is evaluated under different parameters like Data Dropped (Retry Threshold Exceeded), Load, Media acc ess delay and Network Load by using FTP load.

Evaluating the Performance of IPTV over Fixed WiMAX

IEEE specifies different modulation techniques for WiMAX; namely, BPSK, QPSK, 16 QAM and 64 QAM. This paper studies the performance of Internet Protocol Television (IPTV) over Fixed WiMAX system considering different combinations of digital modulation. The performance is studied taking into account a number of key system parameters which include the variation in the video coding, path-loss, scheduling service classes different rated codes in FEC channel coding. The performance study was conducted using OPNET simulation. The performance is studied in terms of packet lost, packet jitter delay, end-to-end delay, and network throughput. Simulation results show that higher order modulation and coding schemes (namely, 16 QAM and 64 QAM) yield better performance than that of QPSK.

Performance Analysis and Evaluation of Hybrid Network using different Integrated Routing Protocols

The increasing demand of computer communication networks are growing rapidly day by day. With the growing need to distribute applications across multiple networks and the availability of high capacity, high-performance intermediate switching nodes, and networks, an efficient routing mechanism has become the core requirement. This research primarily focuses on the design and performance of Hybrid Network incorporating different intra-domain routing algorithms. The performance evaluation of different routing algorithms for the transmission of video- and voice-data streams over Hybrid network is demonstrated in this work.. This allows multiple Ethernet point-to-point links to be bundled into one logical full-duplex channel for Fast Ethernet (10BaseT, 100BaseT, or 1000BaseX). These applications require some QoS support such as guaranteed bandwidth, less delay, less jittering effect and low error rate. The QoS relies on a number of factors along with a suite of robust routing protocols that help to accomplish the task of moving datagram from source to destination with high bandwidth and low delay rate. An effective intra-domain network routing protocol may make distributed applications more efficient across multiple networks with the availability of high capacity and high-performance. A variety of intra-domain routing protocols such as Routing Information Protocol (RIP) and Open Shortest First Protocol (OSPF), Interior Gateway Protocol (IGRP) and Enhanced Interior Gateway Protocol (EIGRP) are available and widely used in designing such high capacity and high performance networks with optimum QoS. We evaluate the performance of these intra-domain routing protocols with IS-IS to recommend the optimum routing protocol to use to provide optimum QoS by means of OPNET Simulator TM. In this thesis work, the following objectives are considered and demonstrated.

The Simulation Research of Campus Network Technology Based on IPv6

Aiming at the issues of smooth transition from IPv4 to IPv6 and interoperability in technical coexistence period about campus network, discussing the technical characteristics of IPv6 protocol, GNS3 and OPNET simulator, combined with the status of weakness of IPv6 technology, lack of IPv6 technology planning and financial support for network upgrade in the vast majority of colleges, adopted the simulation methods to build a network model of IPv4 and IPv6 to achieve the technologies study such as topology design, network configuration and testing, network performance design and evaluation of IPv6 campus network under the low-cost conditions.

Optimising VoIP Traffic over MANET: Leveraging the Power of TORA On-Demand Routing Protocol

Ad hoc Network (MANET) routing protocols studies in the last decade have focused more on proactive routing protocols with many specifics to data traffic. Only fewer works have addressed the issues of reactive protocols supporting voice application. This research work analyses the performance of VoIP application in MANET configured with Temporary Ordered Routing Algorithm (TORA) routing protocol as on-demand routing protocol. The VoIP application is evaluated using four different parameters namely; codec, MAC protocol, mobility and node density in an OPNET simulation environment. The quality of transmission was measured through different performance metrics such as jitter, Mean Opinion Score (MOS), end-to-end delay and throughput. Results show that major metrics that had high impact on the performance of the network included mobility and node density. It research proved that communication in an ad hoc network using TORA is more productive and effective with fewer nodes. It could also be said that given the utilization of TORA routing protocol in MANET, quality of voice communication is disproportionate to node density. Increase in the number of nodes greatly depreciates voice quality. In the whole, the work provides a very good analysis that could help the academia and industries in reaching decisions for a most suiting routing protocol at any given ad hoc voice communication setup.

DoS detection in IEEE 802.11 with the presence of hidden nodes

The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel’s bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm.

Sending Safety Video over WiMAX in Vehicle Communications

This paper reports on the design of an OPNET simulation platform to test the performance of sending real-time safety video over VANET (Vehicular Adhoc NETwork) using the WiMAX technology. To provide a more realistic environment for streaming real-time video, a video model was created based on the study of video traffic traces captured from a realistic vehicular camera, and different design considerations were taken into account. A practical controller over real-time streaming protocol is implemented to control data traffic congestion for future road safety development. Our driving video model was then integrated with the WiMAX OPNET model along with a mobility model based on real road maps. Using this simulation platform, different mobility cases have been studied and the performance evaluated in terms of end-to-end delay, jitter and visual experience.

An Adaptive Channel Scheduling Design for Multi-Hop Handoff Delay Reduction in Internet-Based Wireless Mesh Networks

Seamless handoff support is an essential issue to ensure continuous communications in multi-hop wireless mesh networks (WMNs). Due to the multi-hop transmission of network-layer handoff signaling packets, the handoff performance in WMNs can be largely degraded by the long queueing delay and medium access delay at each mesh router, especially when the backbone traffic volume is high. However, this issue is ignored in existing handoff solutions and multi-channel allocation schemes. In this paper, we address the seamless handoff support from a different perspective and propose a novel channel allocation design in hierarchical WMNs to reduce the queueing delay and medium access delay of handoff signaling packets over multi-hop wireless links and to improve the average channel utilization simultaneously. Both analytical and OPNET simulation results show that the performance of the average channel utilization and total handoff delay can be improved significantly using our proposed channel allocation scheme under various scenarios, as compared to other existing channel allocation and handoff solutions in multi-hop WMNs.

Design and implementation of distributed load balancing and fast handoff for wireless mesh networks

AbstractThe association/handoff procedures are very important towards achieving a balanced operation in 802.11‐based wireless mesh networks. In this paper, we design and implement a cooperative association/handoff scheme, where stations share useful information, and handoff is executed in a seamless manner. Furthermore, we introduce a cross‐layer load balancing mechanism that takes into account uplink and downlink channel conditions, routing performance and congestion control. The proposed heuristic algorithms are inspired by the rapidly designed cooperative protocols and control the communication load of each mesh access point in a distributed manner. We evaluate the performance of our mechanisms through OPNET (www.opnet.com) simulations and testbed experiments. Copyright © 2013 John Wiley & Sons, Ltd.

PERFORMANCE ANALYSIS OF AODV, OLSR, GRP AND DSR ROUTING PROTOCOLS WITH DATABASE LOAD IN MANET

Wireless Technology has an enormous use these days and is still becoming popular from times immemorial . It is at its peak when we talk about research. This is because of the latest technological demands now days arising from Laptops , Wireless devices such as Wireless local area networks (WLANs) etc. Because ofast growing popularity day by day, it has le d wireless technology data rates higher and it has made its price cheaper, which is why wireless Technology is growing so fast. In this paper we have presented some most commonly used routing protocols in MANET and c ompared the performance of AODV, OLSR, GRP and DSR routing protocol by using OPNET simulator 14.5. The performance is e valuated under different parameters like Delay, Loa d, and Media access delay, Network Load, Retransmission and Throughput for Dat abase load.

ANALYSIS OF ZONE ROUTING PROTOCOL IN MANET

MANET is combination of wireless mobile nodes that communicate with each other without any kind of cen tralized control or any device or established infrastructure. Therefore MAN ET routing is a critical task to perform in dynamic network. Without any fixed infrastructure, wireless mobile nodes dynamically e stablish the network. Routing Protocols helps to co mmunicate a mobile node with the other nodes in the network by sending or rthe packets. This research paper provides the overview of ZRP by presenting its functionality. The performance of ZR P (Zone Routing Protocol) is analyzed on the basis of parameters Throughput, Load, Data Dropped and Delay using simulator OPNET 14.0.

Network Density based Analysis of MANET Routing Protocols

Mobile Ad-hoc Network (MANET) is a network with structure less self organizing an autonomous system of mobile nodes which are connected by wireless links. In this work an attempt has been made to compare the performance of three MANET Routing Protocols, such that Pro-active Routing Protocol: OLSR (Optimized Link State Routing Protocol), Reactive Routing Protocol: AODV (Ad-Hoc on Demand Distance Vector), Hybrid Routing Protocol: GRP (Geographic Routing Protocol) by using two different applications i.e. High Definition Video Conferencing and High Load FTP generating different types of data in the networks under different nodes densities (20, 40, 60 and 80) in the networks. All the networks are simulated by using a discrete event simulator OPNET 14.0 and results are gathered by using different performance evaluation metrics. After the intensive simulation, it has found that the hybrid protocols (GRP) outperforms both reactive (AODV) and proactive (OLSR) protocols. General Terms Network density based analysis by using different MANET Routing Protocols

Novel Fastest Retransmission and Rate Control Schemes for Improving TCP Performance in Wireless Ad Hoc Networks

A number of different authors have considered the problem of performance degradation of transmission control protocol (TCP) in wireless ad hoc networks. We herein show that pauses in packet transmission due to packet losses are the fundamental cause of performance degradation of TCP in wireless ad hoc networks. To minimize the duration of packet transmission pauses, we propose a fast retransmission scheme for improving TCP performance in consideration of the inter-operability of previously deployed TCPs in wireless ad hoc networks. We also propose an additional rate control scheme for TCPs to reduce the probability of packet contention. Using OPNET and NS2 simulations, we show that our proposed schemes can provide a much better performance than conventional TCPs.

Performance Analysis of MAC in VDL2 Based on OPNET Simulation

As one of VHF data links of ATN, VDL2 is publicly recognized as the next generation data-link in the transition period. The paper focused in the performance research of MAC, of which p-CSMA is the core protocol, based on network simulation. As the precondition of simulation, we build VDL2 model in an integral way and realize MAC process modules in both ground station side and aircraft side applying dynamic process and queue management mechanism. In the paper, Performance targets are defined to evaluate the system performance. Through simulation, trends between parameters and targets are reached and the relationships are revealed between packet delay and throughput\ packets strength.

DoMaIN: A Novel Dynamic Location Management Solution for Internet-Based Infrastructure Wireless Mesh Networks

Wireless mesh networks (WMNs) have been deployed in many areas. There is an increasing demand for supporting a large number of mobile users in WMNs. As one of the key components in mobility management support, location management serves the purpose of tracking mobile users and locating them prior to establishing new communications. Previous dynamic location management schemes proposed for cellular and wireless local area networks (WLANs) cannot be directly applied to WMNs due to the existence of multihop wireless links in WMNs. Moreover, new design challenges arise when applying location management for silently roaming mobile users in the mesh backbone. Considering the number of wireless hops, an important factor affecting the performance of WMNs, we propose a DoMaIN framework that can help mobile users to decide whether an intra- or intergateway location update (LU) is needed to ensure the best location management performance (i.e., packet delivery) among dynamic location management solutions. In addition, by dynamically guiding mobile users to perform LU to a desirable location entity, the proposed DoMaIN framework can minimize the location management protocol overhead in terms of LU overhead in the mesh backbone. Furthermore, DoMaIN brings extra benefits for supporting a dynamic hop-based LU triggering method that is different from previous dynamic LU triggering schemes proposed for cellular networks and WLANs. We evaluate the performance of DoMaIN in different case studies using OPNET simulations. Comprehensive simulation results demonstrate that DoMaIN outperforms other location management schemes and is a satisfactory location management solution for a large number of mobile users silently and arbitrarily roaming under the wireless mesh backbone.

Detection and Prevention of Selective Forwarding-Based Denial-of-Service Attacks in WSNs

Designing wireless sensor networks (WSNs) that can work reliably in the presence of inside packet drop attackers is very challenging. Current trust mechanisms and avoidance approaches are promising but have their limitations. Avoidance approaches transmit multiple copies of the packets to avoid attackers and cause high overhead. In trust mechanisms, each sensor monitors it neighbors, evaluates their trustworthiness, classifies them as either trustworthy or untrustworthy, and then discards untrustworthy sensors from the network. However, malicious insiders, which are legitimate members of the network and know exactly what their monitoring nodes know, can launch attacks carefully to avoid being detected and discarded from the network. In this paper, we first show that this is possible by introducing a selective forwarding-based denial-of-service (DoS) attack. We then propose an enhanced trust mechanism to detect such attackers and identify their victims. Furthermore, we design two attacker-aware protocols to reroute victim nodes' packets by avoiding the attackers. We conduct extensive OPNET simulations to validate our claims and demonstrate the advantages of our proposed approaches. Finally, as a complementary defensive method to our detection and avoidance approaches, we introduce a prevention routing algorithm that proactively prevents the attack and provide our preliminary results to evaluate its performance.

지오멀티캐스트: 모바일 Ad-hoc 무선 네트워크에서 경로 안정성을 이용한 위치기반 멀티캐스트 라우팅 프로토콜

In this paper, we propose a location based multicast routing protocol, called Geomulticast, in mobile ad-hoc wireless networks. The main features and contributions of the proposed geomulticast are as follows. First, support data transmission to only the specific mobile nodes within a target area. Second, establish stable routing route by using mobility information of nodes. Third, reduce control overhead, power for construction of routing route by using geomulticast guided line information. Fourth, present a theoretical model for establishing stable route. The performance evaluation of the proposed geomulticast is executed by using OPNET simulation and theoretical analysis, and the results of simulation and theoretical analysis have similar patterns. And we can see that data packets are efficiently transmitted to specific user groups within a specific area.