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Mobile Ad hoc Networks (MANETs) are wireless networks, which consist of a collection of mobile nodes with no fixed infrastructure, where each node acts as a router that participates in forwarding data packets. They are a new paradigm of wireless communications for mobile hosts that are resource-constrained with only limited energy, computing power and memory. Previous studies on MANETs concentrated more on energy conservation in an idealistic environment without taking into consideration, the effects of realistic mobility, interference and fading. The definition of realistic mobility models is one of the most critical and, at the same time, difficult aspects of the simulations of networks designed for real mobile ad hoc environments. The reason for this is that most scenarios for which ad hoc networks are used have features such as dynamicity and extreme uncertainties. Thus use of real life measurements is currently almost impossible and most certainly expensive. Hence the commonly used alternative is to simulate the movement patterns and hence the reproduction of movement traces quite similar to human mobility behavior is extremely important. The synthetic models used for movement pattern generation should reflect the movement of the real mobile devices, which are usually carried by humans, so the movement of such devices is necessarily based on human decisions. Regularity is an important characteristic of human movement patterns. All simulated movement models are suspect because there is no means of accessing to what extent they map reality. However it is not difficult to see that random mobility models such as Random Walk, Random Waypoint (default model used in almost all network simulations), etc., generate movements that are most non-humanlike. Hence we need to focus on more realistic mobility models such as Gauss Markov, Manhattan Grid, Reference Point Group Mobility Model (RPGM), Column, Pursue and other Hybrid mobility models. These models capture certain mobility characteristics that emulate the realistic MANETs movement, such as temporal dependency, spatial dependency and geographic restriction. Also a Rayleigh/Ricean fading channel is introduced to obtain a realistic fading environment. The energy consumed by the data, MAC, ARP and RTR packets using IEEE 802.11 MAC protocol with the various mobility models in fading and non-fading channel conditions are obtained using ns-2 simulations and AWK programs. The realistic movement patterns are generated using three different mobility generators BonnMotion Mobility Generator, Toilers Code and Scengen Mobility Generator. This thesis work performs an in-depth study on th eeffects of realistic mobility and fading on energy consumption, packet delivery ratio and control overhead of MANETs.

<p>Technology has reached a point where it has become feasible to develop unmanned aerial vehicles (UAVs), that is aircraft without a human pilot on board. Given that future UAVs can be autonomous and cheap, applications of swarming UAVs are possible. In this thesis we have studied a reconnaissance application using swarming UAVs and how these UAVs can communicate the reconnaissance data. To guide the UAVs in their reconnaissance mission we have proposed a pheromone based mobility model that in a distributed manner guides the UAVs to areas not recently visited. Each UAV has a local pheromone map that it updates based on its reconnaissance scans. The information in the local map is regularly shared with a UAV’s neighbors. Evaluations have shown that the pheromone logic is very good at guiding the UAVs in their cooperative reconnaissance mission in a distributed manner.</p><p>Analyzing the connectivity of the UAVs we found that they were heavily partitioned which meant that contemporaneous communication paths generally were not possible to establish. This means that traditional mobile ad hoc network (MANET) routing protocols like AODV, DSR and GPSR will generally fail. By using node mobility and the store-carry-forward principle of delay-tolerant routing the transfer of messages between nodes is still possible. In this thesis we propose location aware routing for delay-tolerant networks (LAROD). LAROD is a beacon-less geographical routing protocol for intermittently connected mobile ad hoc networks. Using static destinations we have shown by a comparative study that LAROD has almost as good delivery rate as an epidemic routing scheme, but at a substantially lower overhead.</p> / Report code: LiU-Tek-Lic-2008:14

Using pooled European Social Survey data (Rounds 4-7, 2008-2014), we investigate the relationship between intergenerational educational mobility and subjective wellbeing (SWB) for young Europeans (N = 16,050 individuals aged 25-34 from 18 countries). Previous research has been struggling with inconclusive results due to the methodological challenge of disentangling the independent (i.e., "net") effect of social mobility over and above the effects of social origin and destination. We contribute to this line of research by contrasting mobility effects estimated in a conventional linear regression framework with net mobility effects estimated by (non-linear) diagonal mobility models (DMM). We show how model selection influences estimates of mobility effects and how different specifications lead to radically different findings. Using DMM, we estimate how intergenerational educational mobility affects the SWB of young Europeans, differentiating between downward and upward mobility and different country groups. Our results suggest that status loss/gain across generations affects young adults' SWB in addition to the level-effect of ending up in a lower/ higher status position only in Continental Europe.

The thesis investigates the process of modeling and simulation of the mobile ad-hoc networks. It provides a overview of the actual state of art together with a literature survey. Basic ideas of both security issues in mobile ad-hoc networks as well as intrusion detection systems are presented. Additionally some new ideas for improvements - like the AGM mobility model - are proposed, and tested during the simulation proces. As an addition a set of applications designer for automating the simulation processes were created.

Technology has reached a point where it has become feasible to develop unmanned aerial vehicles (UAVs), that is aircraft without a human pilot on board. Given that future UAVs can be autonomous and cheap, applications of swarming UAVs are possible. In this thesis we have studied a reconnaissance application using swarming UAVs and how these UAVs can communicate the reconnaissance data. To guide the UAVs in their reconnaissance mission we have proposed a pheromone based mobility model that in a distributed manner guides the UAVs to areas not recently visited. Each UAV has a local pheromone map that it updates based on its reconnaissance scans. The information in the local map is regularly shared with a UAV’s neighbors. Evaluations have shown that the pheromone logic is very good at guiding the UAVs in their cooperative reconnaissance mission in a distributed manner. Analyzing the connectivity of the UAVs we found that they were heavily partitioned which meant that contemporaneous communication paths generally were not possible to establish. This means that traditional mobile ad hoc network (MANET) routing protocols like AODV, DSR and GPSR will generally fail. By using node mobility and the store-carry-forward principle of delay-tolerant routing the transfer of messages between nodes is still possible. In this thesis we propose location aware routing for delay-tolerant networks (LAROD). LAROD is a beacon-less geographical routing protocol for intermittently connected mobile ad hoc networks. Using static destinations we have shown by a comparative study that LAROD has almost as good delivery rate as an epidemic routing scheme, but at a substantially lower overhead. / <p>Report code: LiU-Tek-Lic-2008:14</p>

Les réseaux véhiculaires sont des systèmes de communication basés sur un échange d'informations de véhicules à infrastructures fixes installées au bord des routes, on parle alors de mode V2I (Vehicle-to-Infrastructure), ou de véhicules à véhicules dit mode V2V (Vehicle-to-Vehicle) ou VANET (Vehicular Ad hoc Network). L'objectif est de fournir aux conducteurs et aux opérateurs de transport des informations sur le trafic routier permettant d'améliorer l'efficacité des systèmes de transport, la sécurité et le confort des usagers. Depuis leur apparition, les VANET ont connu un très grand essor, de nombreux standards, applications et mécanismes de routage ont été proposés pour répondre aux spécificités de cette nouvelle classe de réseaux. Les défis à relever pour leur conception découlent principalement de la forte mobilité des véhicules, de la diversité spatio-temporelle de la densité du trafic et de la propagation des ondes radio en environnement extérieur défavorable à l'établissement des communications sans fil. La difficulté, aussi bien économique que logistique, de la mise en œuvre réelle des réseaux véhiculaires fait de la simulation le moyen le plus largement utilisé pour la conception et l'évaluation des solutions proposées. Cependant la validité des résultats de simulation dépend fortement de la capacité des modèles utilisés à reproduire le plus fidèlement possible les situations réelles. Deux aspects sont essentiellement importants dans les VANET : la mobilité des véhicules et la propagation des ondes radio. Nous proposons dans cette thèse un nouveau modèle de mobilité et un nouveau modèle de propagation d’ondes radio pour réseaux de véhicules en environnement urbain et suburbain. Pour définir des schémas réalistes, ces deux modèles se basent sur des données statiques et dynamiques réelles sur les caractéristiques topographiques et socio-économiques de l'environnement. Ces données décrivent particulièrement la distribution spatio-temporelle des véhicules et les infrastructures présentes dans l'environnement. Trois cas d'études sont présentés dans la thèse pour la validation des modèles développés ; un environnement théorique, urbain ou suburbain, défini par l'utilisateur, notamment le cas Manhattan très utilisé, et deux environnements réels qui représentent des agglomérations de taille moyenne. Une autre contribution de cette thèse est l'étude de la connectivité radio et des performances des protocoles de routage dans les VANET. A partir de graphes dynamiques de connexions représentant la variation des liens radio entre véhicules en déplacement, nous avons analysé et déterminé les propriétés de la topologie des liaisons radio des réseaux véhiculaires. Pour étudier les protocoles de routage, nous avons utilisé le modèle de mobilité et le modèle de propagation radio que nous avons développés en association avec le simulateur de réseaux ns-2. Nous avons comparé les performances des protocoles de routage les plus répandus et déterminé les mécanismes de routage les plus adaptés aux réseaux véhiculaires. / Vehicular networks are communication systems based on information exchange either between vehicles and roadside fixed infrastructure, which is called V2I (Vehicle-to-Infrastructure) mode, or from vehicle to vehicle V2V (Vehicle-to-Vehicle) mode also known as VANET (Vehicular Ad hoc Network). The objective of these networks is to provide drivers and transport authorities the most timely information on road traffic in order to improve the efficiency of transportation systems, users safety and comfort.Since their appearance, the VANET have been greatly developed; many standards, applications and routing mechanisms have been proposed to address the specifics of this new class of networks. The challenges arise mainly from the high vehicles mobility, the spatiotemporal diversity of traffic density and, the radio waves propagation in external environment unfavorable to wireless communications establishment.The difficulty, both economic and logistical, of a real implementation of vehicular networks makes the simulation widely used to conceive and assess the proposed solutions. The validity of simulation results depends strongly on the ability of the models to reproduce as faithfully as possible the real situations. Two aspects are mainly important in the VANET: the simulation of vehicles mobility and radio wave propagation.We propose in this thesis a new mobility model and a new radio propagation model for vehicular networks in urban and suburban environment. To be realistic, these two models are based on real static and dynamic data describing the topographic and socioeconomic characteristics of the environment. These data concern particularly the spatiotemporal vehicles distribution and the description of the infrastructures present in the environment. Three case studies are presented in the thesis to validate the models, a theoretical user-defined urban or suburban environment (the Manhattan case very often used) and two real environments from mean size cities.Another contribution of this thesis is the study of radio connectivity and performance of routing protocols in the VANET. From dynamic graphs representing the variation of the radio links between vehicles in motion, we have analyzed and determined the topology properties of vehicular networks. To study routing protocols, we used the mobility model and the radio propagation model in association with the network simulator ns-2. We have compared the performance of the widespread routing protocols and determined the most adapted routing mechanisms to vehicular networks.

Mobile wireless sensor networks are not widely implemented in the real world, even after years of research carried out in this field. One reason is the lack of understanding of the impact that mobility has on network performance. The simulation and emulation of mobile wireless sensor networks is necessary before they are deployed for the real-world applications. This thesis presents a simulation-based study of different mobility models. The total area coverage that depends on the pattern of node movements is observed through simulations. The spatial distribution of node locations is also studied. Various synthetic mobility models available are explored based on their theoretical descriptions. ‘BonnMotion' is used as the network simulator for investigating different mobility scenarios. The results obtained after simulations are imported to MATLAB and the analysis of node movements is done through various plots and inferences from the data. The comparison of mobility models is also discussed based on their spatial node distribution in the simulated scenarios.

Com base em três modelos de mobilidade MapBasedMovement, RandomWayPoint e RandomWalk presentes no simulador The One, sugerimos e discutimos vários modelos es- tocásticos para mobilidade. Primeiramente, a dinâmica das unidades móveis é reduzida a um processo chamado grafo dinâmico, de forma que a configuração espacial das unidades móveis em cada instante de tempo está resumida em um grafo. Os vértices desse grafo são unidades móveis e não mudam conforme o tempo: consideramos um sistema fechado, as unidades não desaparecem e não aparecem novas. O elo entre duas unidades (vértices) em um instante de tempo significa um contato neste instante (a distância entre as unidades é menor que um raio de contato), assim o conjunto de elos muda durante a evolução do sistema. Em seguida, modelamos a evolução do grafo dinâmico como um conjunto de pro- cessos aleatórios binários de forma que cada componente do processo está associada com um par de unidades móveis indicando presença ou ausência de contato entre elas. Três componentes principais constroem o processo: (i) distribuição de tempo de intercontato, (ii) distribuição de tempo de contato, e (iii) independência/interação entre as unidades. Nesta Tese mostramos teoricamente e através de simulações como escolher todos os três componentes para três modelos de mobilidade mencionados acima na situação de baixa densidade de unidades móveis, chamado DTNs (Delay Tolerant Networks). Considerar a modelagem da mobilidade desse ponto de vista é novo e não existe na literatura, até onde sabemos. Existe uma discussão na literatura sobre o tempo de intercontato, mas não conhecemos os resultados e discussão sobre a distribuição do tempo de contato e a interdependência de processos de contatos. / Based on three mobility models MapBasedMovement, RandomWayPoint and Ran- domWalk present on The One Simulator we suggest and discuss various stochastic mo- dels for mobility. First the dynamics of mobile units is reduced to process called dynamic graph, so that the spatial configuration of mobile units in every moment of time is sum- med up in a graph. The vertices of this graph are mobile units and do not change with the time: consider a closed system, the units dont disappear and not appear new. The link between two units (vertices) in an instant of time means a contact right now (dis- tance between the units is less that the radius contact). So the set of links changes during the system evolution. As a second step, the evolution of dynamic graph model as a set of random processes. Each process component is associated with a pair of mobile units indicating presence or absence of contact between them. Three major components build process: (i) distribution of intercontact time , (ii) distribution of contact time, and (iii) Independence interaction between units. In this work we show theoretically and by si- mulation how to choose all three components for three mobility models mentioned above on the situation of low density of mobile units, called DTNs (Delay Tolerant Networks). Consider the mobility modeling from that point of view is new and does not exist in the literature for our knowledge. There is a discussion in the literature about the intercontact time, but we dont know the results and discussion on the distribution of contact time and the interdependence of contact process.

Wireless sensor and actor networks are used in situations where interaction is required between a network and the environment in which the network is deployed. This research studies the functioning of a single mobile actor deployed in a sparsely connected network. When deployed in a sparsely connected network, an actor has to do more than acting. It has to perform the additional duties of an event collector - collecting events from the naturally occurring clusters - so that it can fulfill its primary obligation as an actor. The path taken by a mobile actor node is generated by a mobility model. The existing random mobility models are non-intelligent mobility models. While they may bring about a chance meeting between an actor and an event, there is no guarantee that these meetings will actually happen. This motivates the development of intelligent mobility models for the actor node, which will generate paths that are reflective of the network in which the actor is deployed. In this thesis, intelligent mobility models for the actor node were developed using the inherent clustering information of a sparsely connected network. These models were applied to an actor node in networks of varying sparseness and the following conclusions were reached: (i) Existing random mobility models are unsuitable for an actor in a sparsely connected network. (ii) High probability of events can be sensed when a sparsely connected network is used. (iii) 100% event detection by the actor node is possible at higher speeds. (iv) When the single actor functioned both as an event collector and as an actor, the number of events acted upon by the actor was very close to the number of events acted upon by an actor in a fully connected network. (v) The Correlation Theory developed in this research suggests using a combination of the intelligent mobility models to obtain the best performance results under all circumstances. (vi) Early detection of events can be supported where it is required. All of the above conclusions justify the deployment of a single actor and a sparsely connected network, either individually or as a combination.