Which could be the role of Hybrid Fibre Coax in Next Generation Access networks?

Next generation access networks (NGAN) will support a renewed communication structure where opportunities lie in the provision of ubiquitous broadband connectivity, a wide variety of new applications, appealing contents and a general support to the sustainable growth of diverse sectors. From their deployment it is expected a wealth of innovations, jobs creation and a new wave of economic growth. In this paper we discuss which could be the role of Hybrid Fibre Coax (HFC) in the Next Generation Access Network (NGAN) roadmap. Thus, we propose a simplified model for making approximate cost calculations for HFC deployment based on the geographic and sociodemographic characteristics of Spain. Considering the latest evolution of HFC based on DOCSIS 3.0 from integrated (I-CMTS) towards modular (M-CMTS), the results from the model are compared with the most competitive NGAN for ultrabroadband speeds: Fibre to the Home (FTTH) based on Gigabitcapable Passive Optical Networks (GPON)

How network operators can enhance ambient assisted living applications through next generation networks

Within the technological framework of Information and Communication Technologies (ICT), consumers are currently requesting multimedia services with simplicity of use, reliability, security and service availability through mobile and fixed access. Network operators are proposing the Next Generation Networks (NGN) to address the challenges of providing both services and network convergence. Apart from these considerations, there is a need to provide social and healthcare assistance services in order to support the progressive aging in the elderly population. In order to achieve this objective, the Ambient Assisted Living (AAL) initiative proposes ICT systems and services to promote autonomy and an independent life among the elderly. This paper describes the design and implementation of a group of services, called “service enablers”, which helps AAL applications to be supported in NGN. The presented enablers are identified to support the teleconsulting applications requirements in an NGN environment, involving the implementation of a virtual waiting room, a virtual whiteboard, a multimedia multiconference and a vital-signs monitoring presence status. A use case is defined and implemented to evaluate the developed enablers' performance.

El núcleo de red en redes de nueva generación

El presente proyecto fin de carrera tiene como objetivo realizar un estudio del núcleo de red en las de redes de nueva generación (NGN) y de cómo la evolución de las redes actuales hacia estos conceptos producirá un cambio en la forma de pensar y desarrollar las redes de comunicaciones del futuro. El estudio esta desglosado en tres grandes partes y se inicia con el análisis de la evolución que ha sufrido el núcleo de red en las redes de comunicaciones móviles digitales desde la implantación de las primeras redes digitales hasta la actualidad abarcando tanto la evolución de las redes troncales como de las redes de acceso así como los cambios que han tenido lugar tanto dentro de las propias estructuras de red de los operadores como la forma de interconectarse entre sus redes. Una segunda parte que constituye el cuerpo teórico del trabajo donde se estudia a nivel funcional y de arquitectura de red el desarrollo de los nuevos modelos de red proporcionados por los organismos de estandarización que dan lugar a la aparición de las redes de nueva generación (NGN) y que constituirán el siguiente paso en la evolución de las redes de comunicaciones hacia una infraestructura de red común para todas las redes de acceso actuales. Y una tercera parte que tiene como objetivo el estudio del grado de transformación que tienen que sufrir el núcleo de red en actuales redes troncales de comunicaciones móviles y terrestres, así como una valoración del estado actual de dicha integración, de las dificultades que están encontrando fabricantes y proveedores de servicio para la implementación de dichas redes en el contexto tecnológico y económico actual y su respectivo análisis de como afectará este cambio a los modelos de negocio de los proveedores de servicios de telecomunicaciones. Finalmente se estudia como se esta llevando a cabo este proceso por medio de un caso práctico de implantación e interconexión de la solución propuesta por un fabricante de equipamiento basándose en los modelos anteriormente expuestos en una red comercial de un operador en España y todas las implicaciones asociadas a esta caso concreto. The object of this work is to provide a deep view about the core network inside next generation network (NGN) and how the evolution of the current comunications networks towards the concepts introduced by these new networks brings a change in the way of think and develop communications networks of the future. This work is composed of three blocks and one real case and it starts with the analysis of the evolution of the core network in digital mobile comunications networks since the beginning of the digital mobile comunications networks deployments until nowadays both in core network side and access network side and how the providers have made changes inside their comunications infrastructure and how they interconnect them with other networks. A second part which is the central theoretical part of this work where it is studied the next generation network models stablished by telecomunications associations and how they will be the next step in the evolution of comunications networks towards a common network infrastructure for all existing access networks. A third part where it is studied the level of transformation that core network in mobile and terrestrial comunications networks have to experienced since current situation up to next generation scenarios and what it is the impact of these changes, the issues that are arising for developers, manufactures and service providers in this process, the way that these changes will improve and shift telecomunications business models and how the current economic and technological context is influencing in the whole process. Finally it is studied a actual case about a proposed solution by a manufacturer that based on the models exposed in second part take place a integration and interconection process in a the comercial network of one telecomunication service providers in Spain. This final part regards to all implications associated with this specific case.

An optimized QoS scheme for IMS-NEMO in heterogeneous networks

The network mobility (NEMO) is proposed to support the mobility management when users move as a whole. In IP Multimedia Subsystem (IMS), the individual Quality of Service (QoS) control for NEMO results in excessive signaling cost. On the other hand, current QoS schemes have two drawbacks: unawareness of the heterogeneous wireless environment and inefficient utilization of the reserved bandwidth. To solve these problems, we present a novel heterogeneous bandwidth sharing (HBS) scheme for QoS provision under IMS-based NEMO (IMS-NEMO). The HBS scheme selects the most suitable access network for each session and enables the new coming non-real-time sessions to share bandwidth with the Variable Bit Rate (VBR) coded media flows. The modeling and simulation results demonstrate that the HBS can satisfy users' QoS requirement and obtain a more efficient use of the scarce wireless bandwidth.

QKD in standard optical telecommunications networks

To perform Quantum Key Distribution, the mastering of the extremely weak signals carried by the quantum channel is required. Transporting these signals without disturbance is customarily done by isolating the quantum channel from any noise sources using a dedicated physical channel. However, to really profit from this technology, a full integration with conventional network technologies would be highly desirable. Trying to use single photon signals with others that carry an average power many orders of magnitude bigger while sharing as much infrastructure with a conventional network as possible brings obvious problems. The purpose of the present paper is to report our efforts in researching the limits of the integration of QKD in modern optical networks scenarios. We have built a full metropolitan area network testbed comprising a backbone and an access network. The emphasis is put in using as much as possible the same industrial grade technology that is actually used in already installed networks, in order to understand the throughput, limits and cost of deploying QKD in a real network.

Requisitos en la infraestructura de red para servicios de comunicación entre paciente y centro sanitario

El presente Proyecto Fin de Carrera consiste en un estudio de los accesos a red que utilizan los servicios a los que están adscritos los usuarios de servicios de teleasistencia, planteando al final del mismo un modelo de previsión de caídas que permita que ese acceso a red no sea un problema para la prestación del servicio. Para poder llegar a los objetivos anteriormente descritos, iniciaremos este documento presentando qué se entiende actualmente como servicios de telemedicina y teleasistencia. Prestaremos atención a los actores que intervienen, usos y beneficios que tienen tanto para los pacientes como para las administraciones públicas. Una vez sepamos en qué consisten, centraremos la atención en las redes de acceso que se utilizan para prestar los servicios de telemedicina, con sus ventajas y desventajas. Puesto que no todos los servicios tienen los mismos requisitos generales de fiabilidad o velocidad de transmisión, veremos cómo se puede garantizar las necesidades de cada tipo de servicio por parte del proveedor de red. El siguiente paso para llegar a establecer el modelo de previsión de caídas será conocer las necesidades técnicas y de los actores para prestar un servicio de teleasistencia en el hogar de un paciente. Esto incluirá estudiar qué equipos se necesitan, cómo gestionarlos y cómo marcar el tráfico para que el operador de red sepa cómo tratarlo según el servicio de teleasistencia que se está utilizando, llevando a generar un modelo de supervisión de enlaces de teleasistencia. Llegados a este punto estaremos ya preparados para establecer un modelo de previsión de caídas de la conexión, describiendo la lógica que se necesite para ello, y poniéndolo en práctica con dos ejemplo concretos: un servicio de telemonitorización domiciliaria y otro servicio de telemonitorización ambulatoria. Para finalizar, realizaremos una recapitulación sobre lo estudiado en este documento y realizaremos una serie de recomendaciones. ABSTRACT. This Thesis is a study of the access network to be used with services assigned to patients that are users of telecare services. In the last chapter we will describe a fall forecasting model that allows the access network to not be an issue for the service. For achieving the objectives described above, this paper will begin with the presentation of what is now understood as telemedicine and telecare services. We pay attention to the actors involved, uses and benefits that they have both for patients and for public administrations. Once we know what telecare means and what requisites they have, we will focus on access networks which are used to provide telemedicine services, with their advantages and disadvantages. Since not all services have the same general requirements of reliability and transmission speed, we will try to see how you can ensure the needs of each type of service from the network provider's point of view. The next step is to establish that the forecasting model of falls will meet the technical needs and actors to provide telecare service in the home of a patient. This will include a study of what equipment is needed, how to manage and how to mark traffic for the network operator knowing how to treat it according to the telecare service being used, and this will lead us to the creation of a model of telecare link monitoring. At this point we are already prepared to establish a forecasting model of connection drops, describing the logic that is needed for this, and putting it into practice with two concrete examples: telemonitoring service and an ambulatory telemonitoring service. Finally, we will have a recap on what has been studied in this paper and will make a series of recommendations.

Quantum key distribution based on selective post-processing in passive optical networks

One of the main obstacles to the widespread adoption of quantum cryptography has been the difficulty of integration into standard optical networks, largely due to the tremendous difference in power of classical signals compared with the single quantum used for quantum key distribution. This makes the technology expensive and hard to deploy. In this letter, we show an easy and straightforward integration method of quantum cryptography into optical access networks. In particular, we analyze how a quantum key distribution system can be seamlessly integrated in a standard access network based on the passive optical and time division multiplexing paradigms. The novelty of this proposal is based on the selective post-processing that allows for the distillation of secret keys avoiding the noise produced by other network users. Importantly, the proposal does not require the modification of the quantum or classical hardware specifications neither the use of any synchronization mechanism between the network and quantum cryptography devices.

Providing 30Mbit/s to Spain’s final third. -A techno-economic assessment.

Since the Digital Agenda for Europe released the Europe2020 flagship, Member States are looking for ways of fulfilling their agreed commitments to fast and ultrafast internet deployment. However, Europe is not a homogenous reality. The economic, geographic, social and demographic features of each country make it a highly diverse region to develop best practices over Next Generation Access Networks (NGAN) deployments. There are special concerns about NGAN deployments for “the final third”, as referred to the last 25% of the country’s population who, usually, live in rural areas. This paper assesses, through a techno-economic analysis, the access cost of providing over 30 Mbps broadband for the final third of Spain`s population in municipalities, which are classified into area types, referred to as geotypes. Fixed and mobile technologies are compared in order to determine which is the most cost-effective technology for each geotype. The demographic limit for fixed networks (cable, fibre and copper) is also discussed. The assessment focuses on the supply side and the results show the access network cost only. The research completes a previous published assessment (Techno-economic analysis of next generation access networks roll-out. The case of platform competition, regulation and public policy in Spain) by including the LTE scenario. The LTE scenario is dimensioned to provide 30 Mbps (best effort) broadband, considering a network take-up of 25%. The Rocket techno-economic model is used to assess a ten-year study period deployment. Nevertheless, the deployment must start in 2014 and be completed by 2020, in order to fulfil the Digital Agenda’s goals. The feasibility of the deployment is defined as the ability to recoup the investment at the end of the study period. This ability is highly related to network take-up and, therefore, to service adoption. Network deployment in each geotype is compared with the cost of the deployment in the Urban geotype and broadband expected penetration rates for clarity and simplicity. Debating the cost-effective deployments for each geotype, while addressing the Digital Agenda’s goals regarding fast and ultrafast internet, is the main purpose of this paper. At the end of the last year, the independent Spanish regulation agency released the Spain broadband coverage report at the first half of 2013. This document claimed that 59% and 52% of Spain’s population was already covered by NGAN capable of providing 30 Mbps and 100 Mbps broadband respectively. HFC, with 47% of population coverage, and FTTH, with 14%, were considered as a 100 Mbps capable NGAN. Meanwhile VDSL, with 12% of the population covered, was the only NGAN network considered for the 30 Mbps segment. Despite not being an NGAN, the 99% population coverage of HSPA networks was also noted in the report. Since mobile operators are also required to provide 30 Mbps broadband to 90% of the population in rural areas by the end of 2020, mobile networks will play a significant role on the achievement of the 30 Mbps goal in Spain’s final third. The assessment indicates the cost of the deployment per cumulative households coverage with 4 different NGANs: FTTH, HFC, VDSL and LTE. Research shows that an investment ranging from €2,700 (VDSL) to €5,400 (HFC) million will be needed to cover the first half of the population with any fixed technology assessed. The results state that at least €3,000 million will be required to cover these areas with the least expensive technology (LTE). However, if we consider the throughput that fixed networks could provide and achievement of the Digital Agenda’s objectives, fixed network deployments are recommended for up to 90% of the population. Fibre and cable deployments could cover up to a maximum of 88% of the Spanish population cost efficiently. As there are some concerns about the service adoption, we recommend VDSL and mobile network deployments for the final third of the population. Despite LTE being able to provide the most economical roll-out, VDSL could also provide 50 Mbps from 75% to 90% of the Spanish population cost efficiently. For this population gap, facility based competition between VDSL providers and LTE providers must be encouraged. Regarding 90% to 98.5% of the Spanish population, LTE deployment is the most appropriate. Since costumers in less populated the municipalities are more sensitive to the cost of the service, we consider that a single network deployment could be most appropriate. Finally, it has become clear that it is not possible to deliver 30Mbps to the final 1.5% of the population cost-efficiently and adoption predictions are not optimistic either. As there are other broadband alternatives able to deliver up to 20 Mbps, in the authors’ opinion, it is not necessary to cover the extreme rural areas, where public financing would be required.

Network convergence and QoS for future multimedia services in the VISION project

The emerging use of real-time 3D-based multimedia applications imposes strict quality of service (QoS) requirements on both access and core networks. These requirements and their impact to provide end-to-end 3D videoconferencing services have been studied within the Spanish-funded VISION project, where different scenarios were implemented showing an agile stereoscopic video call that might be offered to the general public in the near future. In view of the requirements, we designed an integrated access and core converged network architecture which provides the requested QoS to end-to-end IP sessions. Novel functional blocks are proposed to control core optical networks, the functionality of the standard ones is redefined, and the signaling improved to better meet the requirements of future multimedia services. An experimental test-bed to assess the feasibility of the solution was also deployed. In such test-bed, set-up and release of end-to-end sessions meeting specific QoS requirements are shown and the impact of QoS degradation in terms of the user perceived quality degradation is quantified. In addition, scalability results show that the proposed signaling architecture is able to cope with large number of requests introducing almost negligible delay.

A simplified energy consumption model for fiber-based Next Generation Access Networks

ICTs account nowadays for 2% of total carbon emissions. However, in a time when strict measures to reduce energyconsumption in all the industrial and services sectors are required, the ICT sector faces an increase in services and bandwidth demand. The deployment of NextGenerationNetworks (NGN) will be the answer to this new demand and specifically, the NextGenerationAccessNetworks (NGANs) will provide higher bandwidth access to users. Several policy and cost analysis are being carried out to understand the risks and opportunities of new deployments, though the question of which is the role of energyconsumption in NGANs seems off the table. Thus, this paper proposes amodel to analyze the energyconsumption of the main fiber-based NGAN architectures, i.e. Fiber To The House (FTTH) in both Passive Optical Network (PON) and Point-to-Point (PtP) variations, and FTTx/VDSL. The aim of this analysis is to provide deeper insight on the impact of new deployments on the energyconsumption of the ICT sector and the effects of energyconsumption on the life-cycle cost of NGANs. The paper presents also an energyconsumption comparison of the presented architectures, particularized in the specific geographic and demographic distribution of users of Spain, but easily extendable to other countries.

Wireless Sensor Network based on OCDMA for closed environments

An infrared optical wireless system is presented, consisting on autonomous remote nodes communicating with a central node. The network is designed for telecommand/telemetry purposes, comprising a large number of nodes at a low data rate. Simultaneous access is granted by using CDMA techniques, and an appropriate selection of the code family can also keep power consumption to a minimum

An Analysis of Next Generation Access Networks Deployment in rural areas

Next generation access networks (NGAN) will support a renewed electronic communication market where main opportunities lie in the provision of ubiquitous broadband connectivity, applications and content. From their deployment it is expected a wealth of innovations. Within this framework, the project reviews the variety of NGAN deployment options available for rural environments, derives a simple method for approximate cost calculations, and then discusses and compares the results obtained. Data for Spain are used for practical calculations, but the model is applicable with minor modifications to most of the rural areas of European countries. The final part of the paper is devoted to review the techno-economic implications of a network deployment in a rural environment as well as the adequacy and possible developments of the regulatory framework involved

On-chip Monitoring: A Light-Weight Interconnection Network Approach

Current nanometer technologies are subjected to several adverse effects that seriously impact the yield and performance of integrated circuits. Such is the case of within-die parameters uncertainties, varying workload conditions, aging, temperature, etc. Monitoring, calibration and dynamic adaptation have appeared as promising solutions to these issues and many kinds of monitors have been presented recently. In this scenario, where systems with hundreds of monitors of different types have been proposed, the need for light-weight monitoring networks has become essential. In this work we present a light-weight network architecture based on digitization resource sharing of nodes that require a time-to-digital conversion. Our proposal employs a single wire interface, shared among all the nodes in the network, and quantizes the time domain to perform the access multiplexing and transmit the information. It supposes a 16% improvement in area and power consumption compared to traditional approaches.

A Simplified Energy Consumption Model for Fibre-Based Next Generation Access Networks

Presentación realizada en el PhD Seminar del ITS 2011 en Budapest. ICTs (Information and Communication Technologies) currently account for 2% of total carbon emissions. However, although modern standards require strict measures to reduce energy consumption across all industrial and services sectors, the ICT sector also faces an increase in services and bandwidth demand. The deployment of Next Generation Networks (NGN) will be the answer to this new demand; more specifically, Next Generation Access Networks (NGANs) will provide higher bandwidth access to users. Several policy and cost analyses are being carried out to understand the risks and opportunities of new deployments, but the question of what role energy consumption plays in NGANs seems off the table. Thus, this paper proposes a model to analyse the energy consumption of the main fibre-based NGAN architectures: Fibre To The House (FTTH), in both Passive Optical Network (PON) and Point-to-Point (PtP) variations, and FTTx/VDSL. The aim of this analysis is to provide deeper insight on the impact of new deployments on the energy consumption of the ICT sector and the effects of energy consumption on the life-cycle cost of NGANs. The paper also presents an energy consumption comparison of the presented architectures, particularised to the specific geographic and demographic distribution of users of Spain but easily extendable to other countries.

A framework for building distributed social network websites

Las redes son la esencia de comunidades y sociedades humanas; constituyen el entramado en el que nos relacionamos y determinan cómo lo hacemos, cómo se disemina la información o incluso cómo las cosas se llevan a cabo. Pero el protagonismo de las redes va más allá del que adquiere en las redes sociales. Se encuentran en el seno de múltiples estructuras que conocemos, desde las interaciones entre las proteínas dentro de una célula hasta la interconexión de los routers de internet. Las redes sociales están presentes en internet desde sus principios, en el correo electrónico por tomar un ejemplo. Dentro de cada cliente de correo se manejan listas contactos que agregadas constituyen una red social. Sin embargo, ha sido con la aparición de los sitios web de redes sociales cuando este tipo de aplicaciones web han llegado a la conciencia general. Las redes sociales se han situado entre los sitios más populares y con más tráfico de la web. Páginas como Facebook o Twitter manejan cifras asombrosas en cuanto a número de usuarios activos, de tráfico o de tiempo invertido en el sitio. Pero las funcionalidades de red social no están restringidas a las redes sociales orientadas a contactos, aquellas enfocadas a construir tu lista de contactos e interactuar con ellos. Existen otros ejemplos de sitios que aprovechan las redes sociales para aumentar la actividad de los usuarios y su involucración alrededor de algún tipo de contenido. Estos ejemplos van desde una de las redes sociales más antiguas, Flickr, orientada al intercambio de fotografías, hasta Github, la red social de código libre más popular hoy en día. No es una casualidad que la popularidad de estos sitios web venga de la mano de sus funcionalidades de red social. El escenario es más rico aún, ya que los sitios de redes sociales interaccionan entre ellos, compartiendo y exportando listas de contactos, servicios de autenticación y proporcionando un valioso canal para publicitar la actividad de los usuarios en otros sitios web. Esta funcionalidad es reciente y aún les queda un paso hasta que las redes sociales superen su condición de bunkers y lleguen a un estado de verdadera interoperabilidad entre ellas, tal como funcionan hoy en día el correo electrónico o la mensajería instantánea. Este trabajo muestra una tecnología que permite construir sitios web con características de red social distribuída. En primer lugar, se presenta una tecnología para la construcción de un componente intermedio que permite proporcionar cualquier característica de gestión de contenidos al popular marco de desarrollo web modelo-vista-controlador (MVC) Ruby on Rails. Esta técnica constituye una herramienta para desarrolladores que les permita abstraerse de las complejidades de la gestión de contenidos y enfocarse en las particularidades de los propios contenidos. Esta técnica se usará también para proporcionar las características de red social. Se describe una nueva métrica de reusabilidad de código para demostrar la validez del componente intermedio en marcos MVC. En segundo lugar, se analizan las características de los sitios web de redes sociales más populares, con el objetivo de encontrar los patrones comunes que aparecen en ellos. Este análisis servirá como base para definir los requisitos que debe cumplir un marco para construir redes sociales. A continuación se propone una arquitectura de referencia que proporcione este tipo de características. Dicha arquitectura ha sido implementada en un componente, Social Stream, y probada en varias redes sociales, tanto orientadas a contactos como a contenido, en el contexto de una asociación vecinal tanto como en proyectos de investigación financiados por la UE. Ha sido la base de varios proyectos fin de carrera. Además, ha sido publicado como código libre, obteniendo una comunidad creciente y está siendo usado más allá del ámbito de este trabajo. Dicha arquitectura ha permitido la definición de un nuevo modelo de control de acceso social que supera varias limitaciones presentes en los modelos de control de acceso para redes sociales. Más aún, se han analizado casos de estudio de sitios de red social distribuídos, reuniendo un conjunto de caraterísticas que debe cumplir un marco para construir redes sociales distribuídas. Por último, se ha extendido la arquitectura del marco para dar cabida a las características de redes sociales distribuídas. Su implementación ha sido validada en proyectos de investigación financiados por la UE. Abstract Networks are the substance of human communities and societies; they constitute the structural framework on which we relate to each other and determine the way we do it, the way information is diseminated or even the way people get things done. But network prominence goes beyond the importance it acquires in social networks. Networks are found within numerous known structures, from protein interactions inside a cell to router connections on the internet. Social networks are present on the internet since its beginnings, in emails for example. Inside every email client, there are contact lists that added together constitute a social network. However, it has been with the emergence of social network sites (SNS) when these kinds of web applications have reached general awareness. SNS are now among the most popular sites in the web and with the higher traffic. Sites such as Facebook and Twitter hold astonishing figures of active users, traffic and time invested into the sites. Nevertheless, SNS functionalities are not restricted to contact-oriented social networks, those that are focused on building your own list of contacts and interacting with them. There are other examples of sites that leverage social networking to foster user activity and engagement around other types of content. Examples go from early SNS such as Flickr, the photography related networking site, to Github, the most popular social network repository nowadays. It is not an accident that the popularity of these websites comes hand-in-hand with their social network capabilities The scenario is even richer, due to the fact that SNS interact with each other, sharing and exporting contact lists and authentication as well as providing a valuable channel to publize user activity in other sites. These interactions are very recent and they are still finding their way to the point where SNS overcome their condition of data silos to a stage of full interoperability between sites, in the same way email and instant messaging networks work today. This work introduces a technology that allows to rapidly build any kind of distributed social network website. It first introduces a new technique to create middleware that can provide any kind of content management feature to a popular model-view-controller (MVC) web development framework, Ruby on Rails. It provides developers with tools that allow them to abstract from the complexities related with content management and focus on the development of specific content. This same technique is also used to provide the framework with social network features. Additionally, it describes a new metric of code reuse to assert the validity of the kind of middleware that is emerging in MVC frameworks. Secondly, the characteristics of top popular SNS are analysed in order to find the common patterns shown in them. This analysis is the ground for defining the requirements of a framework for building social network websites. Next, a reference architecture for supporting the features found in the analysis is proposed. This architecture has been implemented in a software component, called Social Stream, and tested in several social networks, both contact- and content-oriented, in local neighbourhood associations and EU-founded research projects. It has also been the ground for several Master’s theses. It has been released as a free and open source software that has obtained a growing community and that is now being used beyond the scope of this work. The social architecture has enabled the definition of a new social-based access control model that overcomes some of the limitations currenly present in access control models for social networks. Furthermore, paradigms and case studies in distributed SNS have been analysed, gathering a set of features for distributed social networking. Finally the architecture of the framework has been extended to support distributed SNS capabilities. Its implementation has also been validated in EU-founded research projects.