Internet sharing in community networks

Cotutela Universitat Politècnica de Catalunya i Instituto Superior TécnicoThe majority of the world's population does not have any or adequate Internet access. This implies that the Internet cannot provide universal service, reaching everyone without discrimination. Global access to the Internet for all requires the expansion of network infrastructures and a dramatic reduction in Internet access costs especially in less developed geographical regions. Local communities come together to build their own network infrastructures, known as Community Networks, and provide accessible and affordable local and Internet inter-networking. Sharing resources, such as infrastructure or Internet access, is encouraged at all levels, in order to lower the cost of connectivity and services. Communities can develop their own network infrastructures as a commons, using several interconnected sub-networks when the scale requires it, and sharing several Internet gateways among their participants. Shared Internet access is offered through web proxy gateways, where individuals or organisations share the full or spare capacity of their Internet connections with other participants. However, these gateway nodes may be overloaded by the demand, and their Internet capacity may degrade due to lack of regulation. This thesis investigates whether shared Internet access in community networks can be utilized to provide universal Internet access. As a first step in this direction, in this thesis we explored characteristics, limitations and usability of a concrete shared Internet Web proxy service in community networks. Based on our findings we studied and proposed mechanisms to improve the user experience and fairness of Internet sharing Web proxy services in community networks, without introducing significant overhead to the network and other services. More specifically, we proposed a scalable client-side Internet gateway selection mechanism suitable for heterogeneous environments such as community networks. Finally, we studied and proposed techniques for sharing spare Internet capacity without deteriorating the contributors' performance.La mayoría de la población mundial no tiene ningún o un adecuado acceso a Internet. Esto implica que Internet no puede prestar un servicio universal, llegando a todos sin discriminación. El acceso global a Internet para todos requiere una drástica reducción de los costos de acceso a Internet, especialmente en zonas geográficas y poblaciones menos desarrolladas. Las comunidades locales se organizan para construir sus propias infraestructuras de red, conocidas como redes comunitarias, y proporcionan interconexión local y con Internet de forma accesible y asequible. Se fomenta la compartición de recursos, como la infraestructura o el acceso a Internet, para reducir el coste de la conectividad y los servicios. Las comunidades pueden desarrollar sus propias infraestructuras de red como un recurso común, utilizando varias subredes interconectadas dado su tamaño, y compartiendo varias pasarelas de Internet entre sus participantes. El acceso compartido a Internet se ofrece a través de pasarelas que son proxy web, donde los participantes o las organizaciones comparten la capacidad total o excedente de su conexión a Internet con otros participantes. Sin embargo, estas pasarelas pueden saturarse por la demanda, y su capacidad de acceso a Internet se puede degradar debido la falta de regulación. Esta tesis investiga si las redes comunitarias se pueden utilizar para proporcionar acceso universal a Internet. Como primer paso en esta dirección, exploramos las características, limitaciones y usabilidad de un servicio concreto de acceso compartido a Internet con proxies web en una red comunitaria. Sobre la base de nuestros hallazgos, estudiamos y proponemos mecanismos para mejorar la experiencia del usuario y la equitatividad de la compartición, sin introducir una sobrecarga significativa en la red y a otros servicios. Más específicamente, proponemos un mecanismo escalable de selección de pasarela a Internet del lado del cliente, adecuado para entornos heterogéneos como las redes comunitarias. Además, estudiamos y proponemos técnicas para compartir la capacidad de Internet sin deteriorar el desempeño de los participantes que contribuyen.Postprint (published version

Software defined networking for community network testbeds

Wireless Community Networks have received increasing attention the latest years. In an effort to set the cornerstone for an internet without central authorities and monopolies, network engineers throughout the world have started creating community networks. To enhance this effort, Community-lab, a wireless community networks testbed, was created which allows researchers to experiment with new protocols and applications in a realistic environment. Nevertheless, this testbed does not offer the ability to perform L2 experiments. To address this gap, we developed a platform that allows Community-Lab researchers to perform L2 experiments. Moreover, we decided to reach our goal using Software Defined Networking(SDN) techniques, due to the attention they received lately and their promise for a complete networking solution. Overall, we propose an architecture that allows researchers to perform L2 experiments in a generic community networks testbed. To prove the feasibility of our architecture we implemented it for Community-Lab using the OpenFlow SDN protocol, enabling researchers to manage their L2 topology of their experiment.Peer Reviewe