Network simulations often output a log file, which must be parsed to understand the details of the simulation. Visualizations of these simulations are used to make debugging and analysis easier, and there are many visualizers that will display the simulation in 2D. Those in 3D do not fully utilize 3D graphics operations to visualize asimulation. This thesis explores the ways 3D graphics can be used to further enhance a visualization. To do this, it introduces a new network simulator and a visualizer, consisting of an analyzer, which collects statistics about a simulation, and a renderer, which leverages an existing program package for rendering.

<p>Last decade, a lot of research has been done in wireless communication technologies. Mobile</p><p>nodes such personal digital assistants (PDAs), notebooks and cell phones are nowadays used</p><p>in human’s daily life.</p><p>MANETs are networks consisting of two or more mobile nodes equipped with wireless</p><p>communication and networking capabilities, but they don’t have any network centrilized</p><p>infrastructure.</p><p>In last few years, MANETs have been emerged to be an important researched subject in the</p><p>field of wireless networking.</p><p>MANETs are autonomous; however they can communicate with other external networks such</p><p>the internet. They are linked to such external networks by mobile nodes acting as gateways.</p><p>This kind of networks is known as hybrid MANETs.</p><p>Voice over Internet Protocol (VoIP), is a technology that allows you to make voice calls using</p><p>a Internet connection instead of a regular (or analog) phone line.</p><p>The goal of this thesis is evaluate the performance of VoIP strategies for hybrid MANETs.</p><p>Two different aspects are evaluated, the session establishment performance and the voice</p><p>quality.</p><p>Network Simulator 2 is used to run several simulations, two different applications are used to</p><p>run voice simulations (Session Initiation Protocol and Exponential traffic generator). We</p><p>evaluate two different cases for voice traffics, voice calls between two MANET nodes and</p><p>voice calls between MANET nodes and external nodes.</p><p>After running the simulations, there are some performance parameters which will reveal the</p><p>results. The key findings of the simulations are: adding gateways, number of voice traffic</p><p>flows and the number of hops between source and destinations. There are some interesting</p><p>results which reveal for example, that adding gateways is not always beneficial.</p>

<p>In the last few years, the exploit of ad hoc wireless networks has increased thanks to their</p><p>commercial and military potential. An application of wireless ad hoc networks is Bluetooth</p><p>technology, which allows wireless communication among different devices. As a military</p><p>application, we can report the establishment of communications between groups of soldiers in</p><p>a not safe territory. Additionally, ad hoc networks are useful in emergency operations, where</p><p>no fixed infrastructure is feasible.</p><p>A mobile ad hoc network (MANET) represents a system of wireless mobile nodes that can</p><p>self-organize freely and dynamically into arbitrary and temporary network topology. On one</p><p>hand, they can be quick deployed anywhere at anytime as they eliminate the complexity of</p><p>infrastructure setup. On the other hand, other problems arise, such as route errors or higher</p><p>overhead, caused by the mobility of nodes.</p><p>The main goal of this master’s thesis has been the improvement of the communication</p><p>between MAC 802.11 protocol and DSR (Dynamic Source Routing) protocol, to run in the ns-</p><p>2 network simulator.</p>

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In the last 20 years mobile devices gained an important role in daily life and became must have items for everyone. As mobile devices give us the much needed flexibility and mobility, they also represent one major concern; security. As the information is transmitted from node to node via radio frequencies, an imposter can gain access into a mobile network without the need to gain physical access to firewalls and gateways. Also, as they are light and small, mobile devices are easily lost and often used without any PIN or password protection enabled. Hence, it is not difficult for someone even without any technical knowledge to gain access to such devices if they have been left behind or stolen. As traditional intrusion detection systems are not very effective against this kind of attack, there is a need of a different approach that can assist in the identification of a potential imposter. This thesis begins by assessing the security needs of the mobile devices, and establishes the perceived inadequacy of existing safeguards in this respect. Therefore this research considers using Behaviour-Based Mobile Intrusion Detection System (BeMIDS) that aims to assist the identification of anomalous user activity. This in return presents the two main characteristics needed to classify a legitimate user inside a mobile network: first with whom, when and what type of connection is established and then at where the mobile device is left open. After this the research proposes a novel approach that investigates the application of three machine learning algorithms to profile user behaviour in mobile networks. In BeMIDS, historical user profiles are created and then compared with the real-time ones in order to detect unusual activity in mobile networks. If a user’s behaviour changes, this results in alerting the system as an anomalous activity. Specific examples of behaviours that BeMIDS appears to be particularly sensitive to include duration (of calls and of connection with cell towers), time of day (calls are made and cell towers are connected), and frequency of caller usage. In order to classify a legitimate user over a mobile network the thesis then validates this approach by implementing C4.5, RIPPER and SOM algorithms over MIT’s Reality Mining Dataset. The results support the proposed architecture and present accuracy rate as high as 96% for call logs and 94% for tower logs under training conditions.

In mobile communications networks, a location management scheme is responsible for tracking mobile users. Typically, a location management scheme consists of a location update scheme and a paging scheme. Gau and Haas first proposed the concurrent search(CS) approach that could simultaneously locate a number of mobile users in mobile communications networks. We propose to use the theory of the discrete-time Markov chain to analyze the performance of the concurrent search approach. In particular, we concentrate on the worst case in which each mobile user appears equally likely in all the cells of the network. We analyze the average paging delay, the call blocking probability and the system size. We show that our analytical results are consistent with the simulation results of the concurrent search.

How to reduce handoff drop and increase seamless handoff is a very important issue of Quality-of-Service (QoS) in cellular. Although the Cellular IP which separates local and wide area mobility can significantly improves the performance of existing mobile host protocols (e.g. Mobile IP), especially when mobile hosts migrate frequently, it does not have the ability to support QoS control and needs to emit beacon periodically. Hence, we propose schemes of the admission control, the bandwidth reservation for handoffs, the retransmitting data and the estimated quantity for the useful Request Message to improve the control function of QoS in the Cellular IP. Also we propose another paging way in the Cellular IP, which is, the fast find path algorithm and optimal cross point node. The admission control can limit the quantity of connection in whole networks. The bandwidth reservation particularly used for handoff can reduce the rate of handoff drops. The estimated quantity for the useful "Request Message" ignores the overload with a large number of request messages. The fast find path algorithm and optimal cross point node only apply in the first find eligible routing path. It can reduce the paging time of mobile host and let the mobile host attach fast.

Vehicular Ad Hoc Networks (VANET), a derivative of mobile networks, has the capability to increase the safety, e ciency and comfort of transportation systems, and provide users on-the-road Internet connectivity. Because of its impetus and signi cance in practical scenarios, it becomes a sought after topic in both industry and academia. In this thesis, we focus on the vehicle-to-infrastructure (V2I) drive-thru Internet services in a highway scenario. The road side unit (RSU) along a highway can provide network services for vehicles within the coverage. To enhance the network performance, we propose two strategies. First, to ensure a high network throughput, the RSU uses an admission control strategy to limit the competition among vehicles, and avoid the waste of channel time to the low-data-rate users. Second, based on the vehicle density, we also propose a contention window (CW) adjustment strategy which can reduce the collision probability when the network is congested, and reduce the idle time otherwise. Extensive simulations using network simulator (NS-2) are given, which demonstrate the e ectiveness of the proposed solutions. / Graduate

Last decade, a lot of research has been done in wireless communication technologies. Mobile nodes such personal digital assistants (PDAs), notebooks and cell phones are nowadays used in human’s daily life. MANETs are networks consisting of two or more mobile nodes equipped with wireless communication and networking capabilities, but they don’t have any network centrilized infrastructure. In last few years, MANETs have been emerged to be an important researched subject in the field of wireless networking. MANETs are autonomous; however they can communicate with other external networks such the internet. They are linked to such external networks by mobile nodes acting as gateways. This kind of networks is known as hybrid MANETs. Voice over Internet Protocol (VoIP), is a technology that allows you to make voice calls using a Internet connection instead of a regular (or analog) phone line. The goal of this thesis is evaluate the performance of VoIP strategies for hybrid MANETs. Two different aspects are evaluated, the session establishment performance and the voice quality. Network Simulator 2 is used to run several simulations, two different applications are used to run voice simulations (Session Initiation Protocol and Exponential traffic generator). We evaluate two different cases for voice traffics, voice calls between two MANET nodes and voice calls between MANET nodes and external nodes. After running the simulations, there are some performance parameters which will reveal the results. The key findings of the simulations are: adding gateways, number of voice traffic flows and the number of hops between source and destinations. There are some interesting results which reveal for example, that adding gateways is not always beneficial.

In the last few years, the exploit of ad hoc wireless networks has increased thanks to their commercial and military potential. An application of wireless ad hoc networks is Bluetooth technology, which allows wireless communication among different devices. As a military application, we can report the establishment of communications between groups of soldiers in a not safe territory. Additionally, ad hoc networks are useful in emergency operations, where no fixed infrastructure is feasible. A mobile ad hoc network (MANET) represents a system of wireless mobile nodes that can self-organize freely and dynamically into arbitrary and temporary network topology. On one hand, they can be quick deployed anywhere at anytime as they eliminate the complexity of infrastructure setup. On the other hand, other problems arise, such as route errors or higher overhead, caused by the mobility of nodes. The main goal of this master’s thesis has been the improvement of the communication between MAC 802.11 protocol and DSR (Dynamic Source Routing) protocol, to run in the ns- 2 network simulator.