Uma Rede Móvel Ad Hoc (MANET) consiste em uma coleção de terminais que possuem uma interface de transmissão e recepção sem fio (wireless) e que se movimentam em uma determinada área de abrangência. Geralmente esses terminais fazem uso de freqüências de rádio nas comunicações e configuram uma rede não infraestruturada. As MANETs, também conhecidas como independentes, não necessitam de qualquer infra-estrutura pré-existente para prover comunicação entre os nós, contudo, são utilizadas, principalmente quando integradas à Internet. Essa integração, apesar de possível, normalmente necessita de um gateway que encaminhe os pacotes entre as redes de computadores, respeitando as suas características individuais. Problemas, assim como atrasos e perdas de pacotes, podem ser provocados pelas diferenças intríncias aos protocolos de roteamento. Embora o Internet Engineering Task Force (IETF) proponha diversos protocolos de roteamento para as MANETs, o presente trabalho investiga o protocolo de roteamento Ad hoc On-Demand Distance Vector (AODV), por ser considerado um dos protocolos mais implementados e estudados pelo grupo de trabalho do IETF. O nodo gateway, embora já esteja implementado no protocolo de roteamento AODV (HAMIDIAN, 2003), deve ser capaz de interagir com as funções de roteamento da Internet, trocando tráfego com a mesma, de modo transparente e eficiente. O protocolo AODV, por ser reativo, pode demorar até 0,05 segundos para estabelecer uma rota entre um nodo origem e um nodo destino. Nos padrões atuais esse tempo pode ser considerado exageradamente alto, gerando gargalos entre sub-redes, descarte de pacotes e baixa eficiência. O presente trabalho apresenta uma proposta de customização do protocolo de roteamento AODV com atuação restrita ao nodo gateway. Esta customização consiste na adição de uma métrica de confiabilidade no processo de descoberta e utilização de rotas visando a redução no número de pacotes descartados e um ganho de eficiência no fluxo de dados entre as sub-redes envolvidas. / A Mobile Ad Hoc Network (MANET) consists of a collection of mobile hosts, moving in certain range area, that has a wireless interface for transmission and receiving data. Usually these terminals make use of radio frequencies in communications and configure a non infrastructured network. The MANETs, also known as independent, require no pre-existing infrastructure to provide communication between network mobile nodes, however, are used, preferably when integrated with the Internet. This integration, although possible, usually need a gateway that forwards packets between both computer networks, keeping their individual characteristics. Problems such as delays and packet losses can be caused by differences inherent in the routing protocols. Although the Internet Engineering Task Force (IETF) proposes several routing protocols for MANETs, this paper investigates the Ad hoc On-Demand Distance Vector (AODV) routing protocol, viewed as one of more implemented and studied protocol by the IETF work group. The gateway node, which is already implemented in the AODV routing protocol (Hamidian, 2003), should be able to interact, transparently and efficiently, with the Internet routing functions exchanging traffic between them. The AODV protocol, being reactive, can take up to 0.05 seconds to establish a route between a source node and a destination node. By today's standards this time may be considered excessively high, creating bottlenecks between subnets, packet drop and low efficiency. This paper proposes an AODV routing protocol customization restricted to the gateway node activities. This customization consists of adding reliability metric in the route discovery process and its consequent use in order to reduce the number of dropped packets and get increased efficiency in the data flow between the subnets involved.

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.

With the proliferation of mobile devices and wireless connectivity technologies, mobile social communities offer novel opportunities for targeted marketing by service or product providers. Unfortunately, marketers are still unable to realize the full potential of these markets due to their inability to effectively target right audiences. This thesis presents a novel middleware for identifying spontaneous social communities (SSCs) of mobile users in ad hoc networks in order to facilitate marketers' advertisements. The contributions of the presented work are two fold; the first is a novel model for SSCs that captures their unique dynamic nature, in terms of community structure and interest in different \textit{hot-topics} over time. These time-varying interests are represented through an inferred \textit{community profile prototype} that reflects dominant characteristics of community members. This prototype is then employed to facilitate the identification of new potential members. The selected community prototypes are also used by marketers to identify the right communities for their services or products promotions. The second contribution of this paper is novel distributed techniques for efficient calculation of the community prototypes and identification of potential community links. In contrast to traditional models of detecting fixed and mobile social networks that rely on pre-existing friendships among its members to predict new ones, the proposed model focuses on measuring the degree of similarity between the new user's profile and the profiles of members of each community in order to predict new users' relationships in the community. The adopted model of SSCs can foster many existing and new socially-aware applications such as recommender systems for social events and tools for collaborative work. It is also an ideal target for business-oriented applications such as short-message-service (SMS) advertisement messages, podcasting news feeds in addition to location/context-aware services. The performance of the proposed work was evaluated using the NetLogo platform where obtained experimental results demonstrate the achieved high degree of stability in the resulting communities in addition to the effectiveness of the proposed middleware in terms of the reduction in the number of routing messages required for advertisements.

Over a period of time, it has been studied that a mobile “edge-cloud” formed by hand-held devices could be a productive resource entity for providing a service in the mobile cloud landscape. The ease of access to a pool of devices is much more arbitrary and based purely on the needs of the user. This pool can act as a provider of an infrastructure for various services that can be processed with volunteer node participation, where the node in the vicinity is itself a service provider. This representation of cloud formation to engender a constellation of devices in turn providing a service is the basis for the concept of Mobile Ad-hoc Cloud Computing. In this thesis, an architecture is designed for providing an Infrastructure as a service in Mobile Ad-hoc Cloud Computing. The performance evaluation reveals the gain in execution time while offloading to the mobile ad-hoc cloud. Further, this novel architecture enables discovering a dedicated pool of volunteer devices for computation. An optimized task scheduling algorithm is proposed that provides a coordinated resource allocation. However, failure to maintain the service between heterogeneous networks shows the inability of the present day networks to adapt to frequent changes in a network. Thus, owing to the heavy dependence on the centralized mobile network, the service related issues in a mobile ad-hoc cloud needs to be addressed. As a result, using the principles of Software Defined Networking (SDN), a disruption tolerant Mobile Ad-hoc Cloud framework is proposed. To evaluate this framework a comprehensive case study is provided in this work that shows a round trip time improvement using an SDN controller.

The Internet has become an integral part of our nation's critical socio-economic infrastructure. With its heightened use and growing complexity however, organizations are at greater risk of cyber crimes. To aid in the investigation of crimes committed on or via the Internet, a network forensics analysis tool pulls together needed digital evidence. It provides a platform for performing deep network analysis by capturing, recording and analyzing network events to find out the source of a security attack or other information security incidents. Existing network forensics work has been mostly focused on the Internet and fixed networks. But the exponential growth and use of wireless technologies, coupled with their unprecedented characteristics, necessitates the development of new network forensic analysis tools. This dissertation fostered the emergence of a new research field in cellular and ad-hoc network forensics. It was one of the first works to identify this problem and offer fundamental techniques and tools that laid the groundwork for future research. In particular, it introduced novel methods to record network incidents and report logged incidents. For recording incidents, location is considered essential to documenting network incidents. However, in network topology spaces, location cannot be measured due to absence of a 'distance metric'. Therefore, a novel solution was proposed to label locations of nodes within network topology spaces, and then to authenticate the identity of nodes in ad hoc environments. For reporting logged incidents, a novel technique based on Distributed Hash Tables (DHT) was adopted. Although the direct use of DHTs for reporting logged incidents would result in an uncontrollably recursive traffic, a new mechanism was introduced that overcome this recursive process. These logging and reporting techniques aided forensics over cellular and ad-hoc networks, which in turn increased their ability to track and trace attacks to their source. These techniques were a starting point for further research and development that would result in equipping future ad hoc networks with forensic components to complement existing security mechanisms.

Indiana University-Purdue University Indianapolis (IUPUI) / This thesis discusses about developing a routing protocol of mobile ad hoc networks in a bio inspired manner. Algorithms inspired by collective behaviour of social insect colonies, bird flocking, honey bee dancing, etc., promises to be capable of catering to the challenges faced by tiny wireless sensor networks. Challenges include but are not limited to low bandwidth, low memory, limited battery life, etc. This thesis proposes an energy efficient multi-path routing algorithm based on foraging nature of ant colonies and considers many other meta-heuristic factors to provide good robust paths from source node to destination node in a hope to overcome the challenges posed by resource constrained sensors. / 2020-12-31

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Mobile Ad hoc NETworks (MANETs) have attracted great research interest in recent years. Among many issues, lack of motivation for participating nodes to collaborate forms a major obstacle to the adoption of MANETs. Many contemporary collaboration enforcement techniques employ reputation mechanisms for nodes to avoid and penalize malicious participants. Reputation information is propagated among participants and updated based on complicated trust relationships to thwart false accusation of benign nodes. The aforementioned strategy suffers from low scalability and is likely to be exploited by adversaries. To address these problems, we first propose a finite state model. With this technique, no reputation information is propagated in the network and malicious nodes cannot cause false penalty to benign hosts. Misbehaving node detection is performed on-demand; and malicious node punishment and avoidance are accomplished by only maintaining reputation information within neighboring nodes. This scheme, however, requires that each node equip with a tamper-proof hardware. In the second technique, no such restriction applies. Participating nodes classify their one-hop neighbors through direct observation and misbehaving nodes are penalized within their localities. Data packets are dynamically rerouted to circumvent selfish nodes. In both schemes, overall network performance is greatly enhanced. Our approach significantly simplifies the collaboration enforcement process, incurs low overhead, and is robust against various malicious behaviors. Simulation results based on different system configurations indicate that the proposed technique can significantly improve network performance with very low communication cost.

Mobile Ad hoc Networks (MANETs) are of great interest to researchers and have become very popular in the last few years. One of the great challenges is to provide a routing protocol that is capable of offering the shortest and most reliable path in a MANET in which users are moving continuously and have no base station to be used as a reference for their position. This thesis proposes some new routing protocols based on the angles (directions) of the adjacent mobile nodes and also the node density. In choosing the next node in forming a route, the neighbour node with the closest heading angle to that of the node of interest is selected, so the connection between the source and the destination consists of a series of nodes that are moving in approximately the same direction. The rationale behind this concept is to maintain the connection between the nodes as long as possible. This is in contrast to the well known hop count method, which does not consider the connection lifetime. We propose three enhancements and modifications of the Ad-hoc on demand distance vector (AODV) protocol that can find a suitable path between source and destination using combinations and prioritization of angle direction and hop count. Firstly, we consider that if there are multiple routing paths available, the path with the minimum hop count is selected and when the hop counts are the same the path with the best angle direction is selected. Secondly, if multiple routing paths are available the paths with the best angle direction are chosen but if the angles are the same (fall within the same specified segment), the path with minimum hop count is chosen. Thirdly, if there is more than one path available, we calculate the average of all the heading angles in every path and find the best one (lowest average) from the source to the destination. In MANETs, flooding is a popular message broadcasting technique so we also propose a new scheme for MANETS where the value of the rebroadcast packets for every host node is dynamically adjusted according to the number of its neighbouring nodes. A fixed probabilistic scheme algorithm that can dynamically adjust the rebroadcasting probability at a given node according to its ID is also proposed; Fixed probabilistic schemes are one of the solutions to reduce rebroadcasts and so alleviate the broadcast storm problem. Performance evaluation of the proposed schemes is conducted using the Global Mobile Information System (GloMoSim) network simulator and varying a number of important MANET parameters, including node speed, node density, number of nodes and number of packets, all using a Random Waypoint (RWP) mobility model. Finally, we measure and compare the performance of all the proposed approaches by evaluating them against the standard AODV routing protocol. The simulation results reveal that the proposed approaches give relatively comparable overall performance but which is better than AODV for almost all performance measures and scenarios examined.

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