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![Figure 1: FIFO queue [11]](profile/Adnan-Hussein-Ali/publication/332622462/figure/fig1/AS:751237427380224@1556120368043/FIFO-queue-11_Q320.jpg)
![Figure 2: Priority queuing [11]](profile/Adnan-Hussein-Ali/publication/332622462/figure/fig2/AS:751237427376128@1556120368070/Priority-queuing-11_Q320.jpg)
![Figure 3: WFQ queuing [11]](profile/Adnan-Hussein-Ali/publication/332622462/figure/fig3/AS:751237427363840@1556120368095/WFQ-queuing-11_Q320.jpg)
Voice over Internet Protocol (VoIP) is a service from the internet services that allows users to communicate with each other. Quality of Service (QoS) is very sensitive to delay so that VOIP needs it. The objective of this research is study the effect of different queuing algorithms within the router on VoIP QoS. In this work, simulation tool "OPNE...
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Context 1
... network model for simulation consists from two companies that are located in two different countries around the world. The local area network (LAN) structure for both companies is the same (as shown in Figure 4). There are some important objects in OPNET that are used to simplify and facilitate the work with it. ...
Context 2
... are some important objects in OPNET that are used to simplify and facilitate the work with it. In this research, some of these objects that are used are Application Configuration, Profile Configuration and QoS Attribute Configuration as show in Fig.4: 1. Application Configuration Object: is an object used to define and configure all Applications in the network according to the user requirements. ...
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Voice over Internet Protocol (VoIP) is an application from the internet services that allows us to communicate with each other. VoIP requires Quality of Service (QoS) because it is very sensitive to loss and delay of the information. Therefore, QoS of VoIP is needed to ensure that voice packets are not delayed or lost during the transmission over t...
Citations
... That weight is taken in turn from each queue with a different number of bits depending on the type of traffic in each queue [35]. Using WFQ allows for traffic flows to not be starved and allows guaranteed throughout for all queues [39]. For small flows, it provides a fast service such as VoIP but for larger flows, WFQ will drop large packets. ...
This dissertation investigates the impact of these service mechanisms within a converged
network as this is the main type of network that is operated around the world. While
traditional networks used to only utilise one type of traffic application, a converged network
runs multiple types within the same network without having to have a dedicated network
for each traffic application. With converged networks, the risk of having frequent network
congestion is significantly higher than traditional networks due to the volume of different
traffic types and their resource usage.
Distributed Denial of service (DDoS) attacks affect millions of users and businesses across the globe every year. With the ever-increasing sophistication and complexity of these attacks services and resources are at the mercy of the attacker, with very little in the way of prevention against these kinds of attacks. Voice over internet protocol (VoIP) and Video Conferencing are most affected by these attacks because they rely on real-time packet delivery whereas applications such as Web browsing can be resent. For the client to be satisfied by application performance, Quality of Service (QoS) needs to be measured. This is usually defined in a service level agreement and is the overall quality of an application. For instance, if the QoS of VoIP is not maintained, then the call quality is severely degraded, and thus the call session is lost. This project aimed to investigate the effect that queuing mechanisms have on the level of QoS of two time-sensitive applications (VoIP and Video conferencing) under a DDoS attack. Three common queuing mechanisms have been used; First in First out (FIFO), Weighted Fair Queuing (WFQ) and Priority queuing (PQ). These will aim to help mitigate the congestion created by the DDoS UDP Flood attack. The results of this study will indicate the effect that queuing mechanisms have on QoS while subject to a DDoS UDP Flood attack. FIFO was found to not maintain a good level of QoS throughout the DDoS attack. Whereas WFQ was able to keep a minimal level of QoS but was not sufficient for client acceptability. PQ maintained a stable level of QoS but deteriorated when subject to the DDoS attack. In conclusion, PQ was found to maintain a better level of QoS for both VoIP and Video conferencing for normal traffic operation but reduces to an unacceptable level during the duration of a DDoS Attack. 3 Acknowledgements I would like to thank my Family and friends for their dedicated help and support throughout my studies. I would also like to thank my Supervisor and the University for the opportunity of conducting this project and providing me with the help and support for the completion of this project. 4
A Local Area Network is designed and simulated to investigate the effect of Quality of Service (QoS) on the performance of the network. The experiment examines the performance of non-QoS scenario and QoS scenario. Voice Jitter, Voice Mean Opinion Score value, Voice Packet End-to-End Delay, Voice Packet Delay Variation, Voice traffic received, and Voice traffic sent are used as performance parameters. The result demonstrates a significant difference between the performance of both scenarios. Therefore, the Quality of Service (QoS) has improved the overall performance of the network.
