Towards content-centric geometric routing

Content delivery is a crucial feature of existing cloud and telecom networks. This is confirmed by the tremendous success of media streaming services such as Spotify and Netftix, as well as the content and file-distribution systems such as BitTorrent. A recurring problem in these type of network services is about keeping the protocol overhead as low as possible while maximizing the efficiency of such systems in terms of network delay to customers. In this paper we propose the use of a routing system-inferred coordinate system to improve: i) content server selection upon receiving content requests, and ii) the mapping of content to servers/caches. We describe the required protocol mechanisms, and evaluate potential gains using coordinates of Geometric Tree Routing and compare it to pure IP-based mechanisms or measurement-based content systems relying on coordinates. The proposed approach can be further extended in order to include alternate geometric systems for example supporting hyperbolic geometries

Routing at Large Scale: Advances and Challenges for Complex Networks

International audienceA wide range of social, technological and communication systems can be described as complex networks. Scale-free networks are one of the well-known classes of complex networks in which nodes degree follow a power-law distribution. The design of scalable, adaptive and resilient routing schemes in such networks is very challenging. In this article we present an overview of required routing functionality, categorize the potential design dimensions of routing protocols among existing routing schemes and analyze experimental results and analytical studies performed so far to identify the main trends/trade-offs and draw main conclusions. Besides traditional schemes such as hierarchical/shortest-path path-vector routing, the article pays attention to advances in compact routing and geometric routing since they are known to significantly improve the scalability in terms of memory space. The identified trade-offs and the outcomes of this overview enable more careful conclusions regarding the (in-)suitability of different routing schemes to large-scale complex networks and provide a guideline for future routing research

Ono: an open platform for social robotics

In recent times, the focal point of research in robotics has shifted from industrial ro- bots toward robots that interact with humans in an intuitive and safe manner. This evolution has resulted in the subfield of social robotics, which pertains to robots that function in a human environment and that can communicate with humans in an int- uitive way, e.g. with facial expressions. Social robots have the potential to impact many different aspects of our lives, but one particularly promising application is the use of robots in therapy, such as the treatment of children with autism. Unfortunately, many of the existing social robots are neither suited for practical use in therapy nor for large scale studies, mainly because they are expensive, one-of-a-kind robots that are hard to modify to suit a specific need. We created Ono, a social robotics platform, to tackle these issues. Ono is composed entirely from off-the-shelf components and cheap materials, and can be built at a local FabLab at the fraction of the cost of other robots. Ono is also entirely open source and the modular design further encourages modification and reuse of parts of the platform

Naming and discovery in networks : architecture and economics

In less than three decades, the Internet was transformed from a research network available to the academic community into an international communication infrastructure. Despite its tremendous success, there is a growing consensus in the research community that the Internet has architectural limitations that need to be addressed in a effort to design a future Internet. Among the main technical limitations are the lack of mobility support, and the lack of security and trust. The Internet, and particularly TCP/IP, identifies endpoints using a location/routing identifier, the IP address. Coupling the endpoint identifier to the location identifier hinders mobility and poorly identifies the actual endpoint. On the other hand, the lack of security has been attributed to limitations in both the network and the endpoint. Authentication for example is one of the main concerns in the architecture and is hard to implement partly due to lack of identity support. The general problem that this dissertation is concerned with is that of designing a future Internet. Towards this end, we focus on two specific sub-problems. The first problem is the lack of a framework for thinking about architectures and their design implications. It was obvious after surveying the literature that the majority of the architectural work remains idiosyncratic and descriptions of network architectures are mostly idiomatic. This has led to the overloading of architectural terms, and to the emergence of a large body of network architecture proposals with no clear understanding of their cross similarities, compatibility points, their unique properties, and architectural performance and soundness. On the other hand, the second problem concerns the limitations of traditional naming and discovery schemes in terms of service differentiation and economic incentives. One of the recurring themes in the community is the need to separate an entity\u27s identifier from its locator to enhance mobility and security. Separation of identifier and locator is a widely accepted design principle for a future Internet. Separation however requires a process to translate from the identifier to the locator when discovering a network path to some identified entity. We refer to this process as identifier-based discovery, or simply discovery, and we recognize two limitations that are inherent in the design of traditional discovery schemes. The first limitation is the homogeneity of the service where all entities are assumed to have the same discovery performance requirements. The second limitation is the inherent incentive mismatch as it relates to sharing the cost of discovery. This dissertation addresses both subproblems, the architectural framework as well as the naming and discovery limitations

Towards a reliable seamless mobility support in heterogeneous IP networks

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Next Generation networks (3G and beyond) are evolving towards all IP based systems with the aim to provide global coverage. For Mobility in IP based networks, Mobile IPv6 is considered as a standard by both industry and research community, but this mobility protocol has some reliability issues. There are a number of elements that can interrupt the communication between Mobile Node (MN) and Corresponding Node (CN), however the scope of this research is limited to the following issues only: • Reliability of Mobility Protocol • Home Agent Management • Handovers • Path failures between MN and CN First entity that can disrupt Mobile IPv6 based communication is the Mobility Anchor point itself, i.e. Home Agent. Reliability of Home Agent is addressed first because if this mobility agent is not reliable there would be no reliability of mobile communication. Next scenario where mobile communication can get disrupted is created by MN itself and it is due to its mobility. When a MN moves around, at some point it will be out of range of its active base station and at the same time it may enter the coverage area of another base station. In such a situation, the MN should perform a handover, which is a very slow process. This handover delay is reduced by introducing a “make before break” style handover in IP network. Another situation in which the Mobile IPv6 based communication can fail is when there is a path failure between MN and CN. This situation can be addressed by utilizing multiple interfaces of MN at the same time. One such protocol which can utilize multiple interfaces is SHIM6 but it was not designed to work on mobile node. It was designed for core networks but after some modification in the protocol , it can be deployed on mobile nodes. In this thesis, these issues related to reliability of IPv6 based mobile communication have been addressed

Towards a reliable seamless mobility support in heterogeneous IP networks

Next Generation networks (3G and beyond) are evolving towards all IP based systems with the aim to provide global coverage. For Mobility in IP based networks, Mobile IPv6 is considered as a standard by both industry and research community, but this mobility protocol has some reliability issues. There are a number of elements that can interrupt the communication between Mobile Node (MN) and Corresponding Node (CN), however the scope of this research is limited to the following issues only: • Reliability of Mobility Protocol • Home Agent Management • Handovers • Path failures between MN and CN First entity that can disrupt Mobile IPv6 based communication is the Mobility Anchor point itself, i.e. Home Agent. Reliability of Home Agent is addressed first because if this mobility agent is not reliable there would be no reliability of mobile communication. Next scenario where mobile communication can get disrupted is created by MN itself and it is due to its mobility. When a MN moves around, at some point it will be out of range of its active base station and at the same time it may enter the coverage area of another base station. In such a situation, the MN should perform a handover, which is a very slow process. This handover delay is reduced by introducing a “make before break” style handover in IP network. Another situation in which the Mobile IPv6 based communication can fail is when there is a path failure between MN and CN. This situation can be addressed by utilizing multiple interfaces of MN at the same time. One such protocol which can utilize multiple interfaces is SHIM6 but it was not designed to work on mobile node. It was designed for core networks but after some modification in the protocol , it can be deployed on mobile nodes. In this thesis, these issues related to reliability of IPv6 based mobile communication have been addressed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

An ontology-based approach toward the configuration of heterogeneous network devices

Despite the numerous efforts of standardization, semantic issues remain in effect in many subfields of networking. The inability to exchange data unambiguously between information systems and human resources is an issue that hinders technology implementation, semantic interoperability, service deployment, network management, technology migration, among many others. In this thesis, we will approach the semantic issues in two critical subfields of networking, namely, network configuration management and network addressing architectures. The fact that makes the study in these areas rather appealing is that in both scenarios semantic issues have been around from the very early days of networking. However, as networks continue to grow in size and complexity current practices are becoming neither scalable nor practical. One of the most complex and essential tasks in network management is the configuration of network devices. The lack of comprehensive and standard means for modifying and controlling the configuration of network elements has led to the continuous and extended use of proprietary Command Line Interfaces (CLIs). Unfortunately, CLIs are generally both, device and vendor-specific. In the context of heterogeneous network infrastructures---i.e., networks typically composed of multiple devices from different vendors---the use of several CLIs raises serious Operation, Administration and Management (OAM) issues. Accordingly, network administrators are forced to gain specialized expertise and to continuously keep knowledge and skills up to date as new features, system upgrades or technologies appear. Overall, the utilization of proprietary mechanisms allows neither sharing knowledge consistently between vendors' domains nor reusing configurations to achieve full automation of network configuration tasks---which are typically required in autonomic management. Due to this heterogeneity, CLIs typically provide a help feature which is in turn an useful source of knowledge to enable semantic interpretation of a vendor's configuration space. The large amount of information a network administrator must learn and manage makes Information Extraction (IE) and other forms of natural language analysis of the Artificial Intelligence (AI) field key enablers for the network device configuration space. This thesis presents the design and implementation specification of the first Ontology-Based Information Extraction (OBIE) System from the CLI of network devices for the automation and abstraction of device configurations. Moreover, the so-called semantic overload of IP addresses---wherein addresses are both identifiers and locators of a node at the same time---is one of the main constraints over mobility of network hosts, multi-homing and scalability of the routing system. In light of this, numerous approaches have emerged in an effort to decouple the semantics of the network addressing scheme. In this thesis, we approach this issue from two perspectives, namely, a non-disruptive (i.e., evolutionary) solution to the current Internet and a clean-slate approach for Future Internet. In the first scenario, we analyze the Locator/Identifier Separation Protocol (LISP) as it is currently one of the strongest solutions to the semantic overload issue. However, its adoption is hindered by existing problems in the proposed mapping systems. Herein, we propose the LISP Redundancy Protocol (LRP) aimed to complement the LISP framework and strengthen feasibility of deployment, while at the same time, minimize mapping table size, latency time and maximize reachability in the network. In the second scenario, we explore TARIFA a Next Generation Internet architecture and introduce a novel service-centric addressing scheme which aims to overcome the issues related to routing and semantic overload of IP addresses.A pesar de los numerosos esfuerzos de estandarización, los problemas de semántica continúan en efecto en muchas subáreas de networking. La inabilidad de intercambiar data sin ambiguedad entre sistemas es un problema que limita la interoperabilidad semántica. En esta tesis, abordamos los problemas de semántica en dos áreas: (i) la gestión de configuración y (ii) arquitecturas de direccionamiento. El hecho que hace el estudio en estas áreas de interés, es que los problemas de semántica datan desde los inicios del Internet. Sin embargo, mientras las redes continúan creciendo en tamaño y complejidad, los mecanismos desplegados dejan de ser escalabales y prácticos. Una de las tareas más complejas y esenciales en la gestión de redes es la configuración de equipos. La falta de mecanismos estándar para la modificación y control de la configuración de equipos ha llevado al uso continuado y extendido de interfaces por líneas de comando (CLI). Desafortunadamente, las CLIs son generalmente, específicos por fabricante y dispositivo. En el contexto de redes heterogéneas--es decir, redes típicamente compuestas por múltiples dispositivos de distintos fabricantes--el uso de varias CLIs trae consigo serios problemas de operación, administración y gestión. En consecuencia, los administradores de red se ven forzados a adquirir experiencia en el manejo específico de múltiples tecnologías y además, a mantenerse continuamente actualizados en la medida en que nuevas funcionalidades o tecnologías emergen, o bien con actualizaciones de sistemas operativos. En general, la utilización de mecanismos propietarios no permite compartir conocimientos de forma consistente a lo largo de plataformas heterogéneas, ni reutilizar configuraciones con el objetivo de alcanzar la completa automatización de tareas de configuración--que son típicamente requeridas en el área de gestión autonómica. Debido a esta heterogeneidad, las CLIs suelen proporcionar una función de ayuda que fundamentalmente aporta información para la interpretación semántica del entorno de configuración de un fabricante. La gran cantidad de información que un administrador debe aprender y manejar, hace de la extracción de información y otras formas de análisis de lenguaje natural del campo de Inteligencia Artificial, potenciales herramientas para la configuración de equipos en entornos heterogéneos. Esta tesis presenta el diseño y especificaciones de implementación del primer sistema de extracción de información basada en ontologías desde el CLI de dispositivos de red, para la automatización y abstracción de configuraciones. Por otra parte, la denominada sobrecarga semántica de direcciones IP--en donde, las direcciones son identificadores y localizadores al mismo tiempo--es una de las principales limitaciones sobre mobilidad, multi-homing y escalabilidad del sistema de enrutamiento. Por esta razón, numerosas propuestas han emergido en un esfuerzo por desacoplar la semántica del esquema de direccionamiento de las redes actuales. En esta tesis, abordamos este problema desde dos perspectivas, la primera de ellas una aproximación no-disruptiva (es decir, evolucionaria) al problema del Internet actual y la segunda, una nueva propuesta en torno a futuras arquitecturas del Internet. En el primer escenario, analizamos el protocolo LISP (del inglés, Locator/Identifier Separation Protocol) ya que es en efecto, una de las soluciones con mayor potencial para la resolucion del problema de semántica. Sin embargo, su adopción está limitada por problemas en los sistemas de mapeo propuestos. En esta tesis, proponemos LRP (del inglés, LISP Redundancy Protocol) un protocolo destinado a complementar LISP e incrementar la factibilidad de despliegue, a la vez que, reduce el tamaño de las tablas de mapeo, tiempo de latencia y maximiza accesibilidad. En el segundo escenario, exploramos TARIFA una arquitectura de red de nueva generación e introducimos un novedoso esquema de direccionamiento orientado a servicios