The all-over trend for an universal access and ubiquitous access to the Internet is driving a revolution in our societies. In order to support this era of nomadic applications, new flexible network architectures have emerged. They are referred to as “wireless ad-hoc networks.” Since human-operated devices will more likely be used indoor, it leads to many issues related to the strength of the fading in this environment. Recently, it has been suggested that a possible interaction might exist between various parameters of the ad-hoc networks and, more precisely, between the propagation model and the routing protocol. To address this question, we present in this dissertation a cross-layer perspective of the analysis of these indoor ad-hoc networks. Our reasoning is made of four stages. First, the cross-layer interactions are analyzed by the means of multivariate statistical techniques. Since a cross-layering between the physical layer and the routing protocol has been proven to be significant, we further investigate the possible development a physical layer-constrained routing algorithm. Second, fundamental equations governing the wireless telecommunications systems are developed in order to provide insightful informations on how a reliable routing strategy should be implemented in a strongly-faded environment. After that, and in order to allow a better spatial reuse, the routing protocol we propose is further enhanced by the adjonction of a power control algorithm. This last feature is extensively analyzed and a closed-form expression of the link probability of outage in presence of non-homogeneous transmission powers is given. Numerous simulations corroborate the applicability and the performance of the derived protocol. Also, we evaluate the gain, in terms of radio channel ressources, that has been achieved by the means of the power control algorithm. Third, an architecture for the interconnection with a cellular network is investigated. A closed-form expression of the relaying stability of a node is given. This equation expresses the minimal requirement that a relaying node from the ad-hoc network must fullfil in order to bridge properly the connections to the base-station. Finally, a real-life implementation is provided as a validation of the applicability of this novel ad-hoc routing protocol. It is concluded that, both from the performance and the spatial re-use point-of-views, it can be taken advantage from the cross-layering between the physical and the routing layers to positively enhance the networking architectures deployed in an indoor environment.

Today's society has developed a reliance on networking infrastructures. Health, financial, and many other institutions deploy mission critical and even life critical applications on local networks and the global Internet. The security of this infrastructure has been called into question over the last decade. In particular, the protocols directing traffic through the network have been found to be vulnerable. One such protocol is the Open Shortest Path First (OSPF) protocol. This thesis proposes a security extension to OSPF containing a decentralized certificate authentication scheme (DecentCA) that eliminates the single point of failure/attack present in current OSPF security extensions. An analysis of the security of the DecentCA is performed. Furthermore, an implementation of DecentCA in the Quagga routing software suite is accomplished.

Wireless sensor networks(WSNs) are different to traditional networks and are highly dependent on applications, thus traditional routing protocols cannot be applied efficiently to the networks. As the variability of both the application and the network architecture, the majority of the attention, therefore, has been given to the routing protocols. This work surveys and evaluates state-of-the-art routing protocols based on many factors including energy efficiency, delay andcomplexity, and presents several classifications for the various approaches pursued. Additionally, more attention is paid to several routing protocols and their advantages and disadvantages and, indeed, this work implements two of selected protocols, LEACH and THVRG, on the OPNET, and compares them in many aspects based on a large amount of experimental data. The survey also provides a valuable framework for comparing new and existing routing protocols. According to the evaluation for the performance of the routing protocols, this thesis provides assistance in relation to further improving the performance in relation to routing protocols. Finally, future research strategies and trends in relation to routing technology in wireless sensor networks are also provided.

1. CONTEXTO1.1. MANETMANET (Mobile and Ad hoc NETworks) (Redes móviles sin cables) son redes formadas por nodos móviles. Se comunican sin cables i lo hacen de manera 'ad hoc'. En este tipo de redes, los protocolos de enrutamiento tienen que ser diferentes de los utilizados en redes fijas.Hoy en día, existen protocolos de enrutamiento capaces de operar en este tipo de redes. No obstante, son completamente inseguras y confían en que los nodos no actuarán de manera malintencionada. En una red donde no se puede contar con la presencia de servidores centrales, se necesita que los nodos puedan comunicarse sin el riesgo de que otros nodos se hagan pasar por aquellos con quien quieren comunicarse. En una red donde todo el mundo es anónimo conceptos como identidad y confianza deben ser redefinidos.1.2. AODVAd Hoc On-Demand Vector Routing (AODV) es un protocolo de enrutamiento reactivo para redes MANET. Esto significa que AODV no hace nada hasta que un nodo necesita transmitir un paquete a otro nodo para el cual no tiene ruta. AODV sólo mantiene rutas entre nodos que necesitan comunicarse. Sus mensajes no contienen información de toda la ruta, solo contienen información sobre el origen i el destino. Por lo tanto los mensajes de AODV tienen tamaño constante independientemente del numero de nodos de la ruta. Utiliza números de secuencia para especificar lo reciente que es una ruta (en relación con otra), lo cual garantiza ausencia de 'loops' (bucles).En AODV, un nodo realiza un descubrimiento de ruta haciendo un 'flooding' de la red con un mensaje llamado 'Route Request' (RREQ). Una vez llega a un nodo que conoce la ruta pedida responde con un 'Route Reply' (RREP) que viaja de vuelta al originador del RREQ. Después de esto, todos los nodos de la ruta descubierta conocen las rutas hacia los dos extremos de la ruta.2. CONTRIBUTIONS2.1. SAODVSAODV (Secure Ad hoc On-Demand Distance Vector) es una extensión de AODV que protege el mecanismo de descubrimiento de ruta. Proporciona funcionalidades de seguridad como ahora integridad i autenticación.Se utilizan firmas digitales para autenticar los campos de los mensajes que no son modificados en ruta y cadenas de hash para proteger el 'hop count' (que es el único campo que se modifica en ruta).2.2. SAKMSAKM (Simple Ad hoc Key Management) proporciona un sistema de gestión de llaves que hace posible para cada nodo obtener las llaves públicas de los otros nodos de la red. Además, permite que cada nodo pueda verificar la relación entre la identidad de un nodo y la llave pública de otro.Esto se consigue a través del uso de direcciones estadísticamente únicas y criptográficamente verificables.2.2.1. Verificación pospuestaEl método 'verificación pospuesta' permite tener rutas pendientes de verificación. Estas serán verificadas cuando el procesador disponga de tiempo para ello y (en cualquier caso) antes de que esas rutas deban ser utilizadas para transmitir paquetes.2.3. Detección de atajosCuando un protocolo de enrutamiento para redes MANET realiza un descubrimiento de ruta, no descubre la ruta más corta sino la ruta a través de la cual el mensaje de petición de ruta viajó más rápidamente. Además, debido a que los nodos son móviles, la ruta que era la más corta en el momento del descubrimiento puede dejar de ser-lo en breve. Esto causa un retraso de transmisión mucho mayor de lo necesario y provoca muchas más colisiones de paquetes.Para evitar esto, los nodos podrían realizar descubrimientos de atajos periódicos para las rutas que están siendo utilizadas. Este mismo mecanismo puede ser utilizado para 'recuperar' rutas que se han roto. / 1. BACKGROUND1.1. MANETMANET (Mobile and Ad hoc NETworks) are networks formed by nodes that are mobile. They use wireless communication to speak among them and they do it in an ad hoc manner. In this kind of networks, routing protocols have to be different than from the ones used for fixed networks. In addition, nodes use the air to communicate, so a lot of nodes might hear what a node transmits and there are messages that are lost due to collisions.Nowadays, routing in such scenario has been achieved. Nevertheless, if it has to be broadly used, it is necessary to be able to do it in a secure way. In a network where the existance of central servers cannot be expected, it is needed that nodes will be able to communicate without the risk of malicious nodes impersonating the entities they want to communicate with. In a network where everybody is anonymous, identity and trust need to be redefined.1.2. AODVAd Hoc On-Demand Vector Routing (AODV) protocol is a reactive routing protocol for ad hoc and mobile networks. That means that AODV does nothing until a node needs to transmit a packet to a node for which it does not know a route. In addition, it only maintains routes between nodes which need to communicate. Its routing messages do not contain information about the whole route path, but only about the source and the destination. Therefore, routing messages have a constant size, independently of the number of hops of the route. It uses destination sequence numbers to specify how fresh a route is (in relation to another), which is used to grant loop freedom.In AODV, a node does route discovery by flooding the network with a 'Route Request' message (RREQ). Once it reaches a node that knows the requested route, it replies with a 'Route Reply' message (RREP) that travels back to the originator of the RREQ. After this, all the nodes of the discovered path have routes to both ends of the path. 2. CONTRIBUTIONS2.1. SAODVThe Secure Ad hoc On-Demand Distance Vector (SAODV) is an extension of the AODV routing protocol that can be used to protect the route discovery mechanism providing security features like integrity and authentication.Two mechanisms are used to secure the AODV messages: digital signatures to authenticate the non-mutable fields of the messages, and hash chains to secure the hop count information (the only mutable information in the messages).The information relative to the hash chains and the signatures is transmitted with the AODV message as an extension message.2.2. SAKMSimple Ad hoc Key Management (SAKM) provides a key management system that makes it possible for each ad hoc node to obtain public keys from the other nodes of the network. Further, each ad hoc node is capable of securely verifying the association between the identity of a given ad hoc node and the public key of that node.This is achieved by using statistically unique and cryptographically verifiable address.2.2.1. Delayed VerificationDelayed verification allows to have route entries and route entry deletions in the routing table that are pending of verification. They will be verified whenever the node has spared processor time or before these entries should be used to forward data packages.2.3. Short Cut DetectionWhen a routing protocol for MANET networks does a route discovery, it does not discover the shortest route but the route through which the route request flood traveled faster. In addition, since nodes are moving, a route that was the shortest one at discovery time might stop being so in quite a short period of time. This causes, not only a much bigger end-to-end delay, but also more collisions and a faster power consumption.In order to avoid all the performance loss due to these problems, nodes could periodically discover shortcuts to the active routes that can be used with any destination vector routing protocol. The same mechanism can be used also as a bidirectional route recovery mechanism.

An ad-hoc network is a packet radio network in which individual mobile nodes perform routing functions. Typically, an ad-hoc networking concept allows users wanting to communicate with each other while forming a temporary network, without any form of centralized administration. Each node participating in the network performs both the host and router function, and willing to forward packets for other nodes. For this purpose a routing protocol is needed. A novel approach utilizes the uniqueness of such a network i. e. distance, location and speed of the nodes, introducing a Distance Routing Effect Algorithm for Mobility (DREAM). The protocol uses the <i>distance effect</i> and the <i>mobility rate</i> as a means to assure routing accuracy. When data needs to be exchanged between two nodes, the directional algorithm sends messages in the recorded direction of the destination node, guaranteeing the delivery by following the direction. The improved algorithm suggested within this thesis project includes an additional parameter, direction of travel, as a means of determining the location of a destination node. When data needs to be exchanged between two nodes, the directional algorithm sends messages in the recorded direction of the destination node, guaranteeing the delivery by following the direction. The end result is an enhancement to the delivery ratio, of the sent to the received packet. This also allows the reduction in the number of control packets that need to be distributed, reducing the overall control overhead of the Improved Dream protocol.

An ad-hoc network is a packet radio network in which individual mobile nodes perform routing functions. Typically, an ad-hoc networking concept allows users wanting to communicate with each other while forming a temporary network, without any form of centralized administration. Each node participating in the network performs both the host and router function, and willing to forward packets for other nodes. For this purpose a routing protocol is needed. A novel approach utilizes the uniqueness of such a network i. e. distance, location and speed of the nodes, introducing a Distance Routing Effect Algorithm for Mobility (DREAM). The protocol uses the <i>distance effect</i> and the <i>mobility rate</i> as a means to assure routing accuracy. When data needs to be exchanged between two nodes, the directional algorithm sends messages in the recorded direction of the destination node, guaranteeing the delivery by following the direction. The improved algorithm suggested within this thesis project includes an additional parameter, direction of travel, as a means of determining the location of a destination node. When data needs to be exchanged between two nodes, the directional algorithm sends messages in the recorded direction of the destination node, guaranteeing the delivery by following the direction. The end result is an enhancement to the delivery ratio, of the sent to the received packet. This also allows the reduction in the number of control packets that need to be distributed, reducing the overall control overhead of the Improved Dream protocol.

Thesis--Auburn University, 2007. / Abstract. Includes bibliographic references (p.44-46).

Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 84-86). Also available via World Wide Web.

Thesis (Ph.D.)--University of Central Florida, 2009. / Adviser: Kien A. Hua. Includes bibliographical references (p. 131-138).

Thesis (M.S.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 163-166)