SDN Architecture and Southbound APIs for IPv6 Segment Routing Enabled Wide Area Networks

The SRv6 architecture (Segment Routing based on IPv6 data plane) is a promising solution to support services like Traffic Engineering, Service Function Chaining and Virtual Private Networks in IPv6 backbones and datacenters. The SRv6 architecture has interesting scalability properties as it reduces the amount of state information that needs to be configured in the nodes to support the network services. In this paper, we describe the advantages of complementing the SRv6 technology with an SDN based approach in backbone networks. We discuss the architecture of a SRv6 enabled network based on Linux nodes. In addition, we present the design and implementation of the Southbound API between the SDN controller and the SRv6 device. We have defined a data-model and four different implementations of the API, respectively based on gRPC, REST, NETCONF and remote Command Line Interface (CLI). Since it is important to support both the development and testing aspects we have realized an Intent based emulation system to build realistic and reproducible experiments. This collection of tools automate most of the configuration aspects relieving the experimenter from a significant effort. Finally, we have realized an evaluation of some performance aspects of our architecture and of the different variants of the Southbound APIs and we have analyzed the effects of the configuration updates in the SRv6 enabled nodes

Segment Routing: a Comprehensive Survey of Research Activities, Standardization Efforts and Implementation Results

Fixed and mobile telecom operators, enterprise network operators and cloud providers strive to face the challenging demands coming from the evolution of IP networks (e.g. huge bandwidth requirements, integration of billions of devices and millions of services in the cloud). Proposed in the early 2010s, Segment Routing (SR) architecture helps face these challenging demands, and it is currently being adopted and deployed. SR architecture is based on the concept of source routing and has interesting scalability properties, as it dramatically reduces the amount of state information to be configured in the core nodes to support complex services. SR architecture was first implemented with the MPLS dataplane and then, quite recently, with the IPv6 dataplane (SRv6). IPv6 SR architecture (SRv6) has been extended from the simple steering of packets across nodes to a general network programming approach, making it very suitable for use cases such as Service Function Chaining and Network Function Virtualization. In this paper we present a tutorial and a comprehensive survey on SR technology, analyzing standardization efforts, patents, research activities and implementation results. We start with an introduction on the motivations for Segment Routing and an overview of its evolution and standardization. Then, we provide a tutorial on Segment Routing technology, with a focus on the novel SRv6 solution. We discuss the standardization efforts and the patents providing details on the most important documents and mentioning other ongoing activities. We then thoroughly analyze research activities according to a taxonomy. We have identified 8 main categories during our analysis of the current state of play: Monitoring, Traffic Engineering, Failure Recovery, Centrally Controlled Architectures, Path Encoding, Network Programming, Performance Evaluation and Miscellaneous...Comment: SUBMITTED TO IEEE COMMUNICATIONS SURVEYS & TUTORIAL

Integrated IT and SDN Orchestration of multi-domain multi-layer transport networks

Telecom operators networks' management and control remains partitioned by technology, equipment supplier and networking layer. In some segments, the network operations are highly costly due to the need of the individual, and even manual, configuration of the network equipment by highly specialized personnel. In multi-vendor networks, expensive and never ending integration processes between Network Management Systems (NMSs) and the rest of systems (OSSs, BSSs) is a common situation, due to lack of adoption of standard interfaces in the management systems of the different equipment suppliers. Moreover, the increasing impact of the new traffic flows introduced by the deployment of massive Data Centers (DCs) is also imposing new challenges that traditional networking is not ready to overcome. The Fifth Generation of Mobile Technology (5G) is also introducing stringent network requirements such as the need of connecting to the network billions of new devices in IoT paradigm, new ultra-low latency applications (i.e., remote surgery) and vehicular communications. All these new services, together with enhanced broadband network access, are supposed to be delivered over the same network infrastructure. In this PhD Thesis, an holistic view of Network and Cloud Computing resources, based on the recent innovations introduced by Software Defined Networking (SDN), is proposed as the solution for designing an end-to-end multi-layer, multi-technology and multi-domain cloud and transport network management architecture, capable to offer end-to-end services from the DC networks to customers access networks and the virtualization of network resources, allowing new ways of slicing the network resources for the forthcoming 5G deployments. The first contribution of this PhD Thesis deals with the design and validation of SDN based network orchestration architectures capable to improve the current solutions for the management and control of multi-layer, multi-domain backbone transport networks. These problems have been assessed and progressively solved by different control and management architectures which has been designed and evaluated in real evaluation environments. One of the major findings of this work has been the need of developed a common information model for transport network's management, capable to describe the resources and services of multilayer networks. In this line, the Control Orchestration Protocol (COP) has been proposed as a first contriution towards an standard management interface based on the main principles driven by SDN. Furthermore, this PhD Thesis introduces a novel architecture capable to coordinate the management of IT computing resources together with inter- and intra-DC networks. The provisioning and migration of virtual machines together with the dynamic reconfiguration of the network has been successfully demonstrated in a feasible timescale. Moreover, a resource optimization engine is introduced in the architecture to introduce optimization algorithms capable to solve allocation problems such the optimal deployment of Virtual Machine Graphs over different DCs locations minimizing the inter-DC network resources allocation. A baseline blocking probability results over different network loads are also presented. The third major contribution is the result of the previous two. With a converged cloud and network infrastructure controlled and operated jointly, the holistic view of the network allows the on-demand provisioning of network slices consisting of dedicated network and cloud resources over a distributed DC infrastructure interconnected by an optical transport network. The last chapters of this thesis discuss the management and orchestration of 5G slices based over the control and management components designed in the previous chapters. The design of one of the first network slicing architectures and the deployment of a 5G network slice in a real Testbed, is one of the major contributions of this PhD Thesis.La gestión y el control de las redes de los operadores de red (Telcos), todavía hoy, está segmentado por tecnología, por proveedor de equipamiento y por capa de red. En algunos segmentos (por ejemplo en IP) la operación de la red es tremendamente costosa, ya que en muchos casos aún se requiere con guración individual, e incluso manual, de los equipos por parte de personal altamente especializado. En redes con múltiples proveedores, los procesos de integración entre los sistemas de gestión de red (NMS) y el resto de sistemas (p. ej., OSS/BSS) son habitualmente largos y extremadamente costosos debido a la falta de adopción de interfaces estándar por parte de los diferentes proveedores de red. Además, el impacto creciente en las redes de transporte de los nuevos flujos de tráfico introducidos por el despliegue masivo de Data Centers (DC), introduce nuevos desafíos que las arquitecturas de gestión y control de las redes tradicionales no están preparadas para afrontar. La quinta generación de tecnología móvil (5G) introduce nuevos requisitos de red, como la necesidad de conectar a la red billones de dispositivos nuevos (Internet de las cosas - IoT), aplicaciones de ultra baja latencia (p. ej., cirugía a distancia) y las comunicaciones vehiculares. Todos estos servicios, junto con un acceso mejorado a la red de banda ancha, deberán ser proporcionados a través de la misma infraestructura de red. Esta tesis doctoral propone una visión holística de los recursos de red y cloud, basada en los principios introducidos por Software Defined Networking (SDN), como la solución para el diseño de una arquitectura de gestión extremo a extremo (E2E) para escenarios de red multi-capa y multi-dominio, capaz de ofrecer servicios de E2E, desde las redes intra-DC hasta las redes de acceso, y ofrecer ademas virtualización de los recursos de la red, permitiendo nuevas formas de segmentación en las redes de transporte y la infrastructura de cloud, para los próximos despliegues de 5G. La primera contribución de esta tesis consiste en la validación de arquitecturas de orquestración de red, basadas en SDN, para la gestión y control de redes de transporte troncales multi-dominio y multi-capa. Estos problemas (gestion de redes multi-capa y multi-dominio), han sido evaluados de manera incremental, mediante el diseño y la evaluación experimental, en entornos de pruebas reales, de diferentes arquitecturas de control y gestión. Uno de los principales hallazgos de este trabajo ha sido la necesidad de un modelo de información común para las interfaces de gestión entre entidades de control SDN. En esta línea, el Protocolo de Control Orchestration (COP) ha sido propuesto como interfaz de gestión de red estándar para redes SDN de transporte multi-capa. Además, en esta tesis presentamos una arquitectura capaz de coordinar la gestión de los recursos IT y red. La provisión y la migración de máquinas virtuales junto con la reconfiguración dinámica de la red, han sido demostradas con éxito en una escala de tiempo factible. Además, la arquitectura incorpora una plataforma para la ejecución de algoritmos de optimización de recursos capaces de resolver diferentes problemas de asignación, como el despliegue óptimo de Grafos de Máquinas Virtuales (VMG) en diferentes DCs que minimizan la asignación de recursos de red. Esta tesis propone una solución para este problema, que ha sido evaluada en terminos de probabilidad de bloqueo para diferentes cargas de red. La tercera contribución es el resultado de las dos anteriores. La arquitectura integrada de red y cloud presentada permite la creación bajo demanda de "network slices", que consisten en sub-conjuntos de recursos de red y cloud dedicados para diferentes clientes sobre una infraestructura común. El diseño de una de las primeras arquitecturas de "network slicing" y el despliegue de un "slice" de red 5G totalmente operativo en un Testbed real, es una de las principales contribuciones de esta tesis.La gestió i el control de les xarxes dels operadors de telecomunicacions (Telcos), encara avui, està segmentat per tecnologia, per proveïdors d’equipament i per capes de xarxa. En alguns segments (Per exemple en IP) l’operació de la xarxa és tremendament costosa, ja que en molts casos encara es requereix de configuració individual, i fins i tot manual, dels equips per part de personal altament especialitzat. En xarxes amb múltiples proveïdors, els processos d’integració entre els Sistemes de gestió de xarxa (NMS) i la resta de sistemes (per exemple, Sistemes de suport d’operacions - OSS i Sistemes de suport de negocis - BSS) són habitualment interminables i extremadament costosos a causa de la falta d’adopció d’interfícies estàndard per part dels diferents proveïdors de xarxa. A més, l’impacte creixent en les xarxes de transport dels nous fluxos de trànsit introduïts pel desplegament massius de Data Centers (DC), introdueix nous desafiaments que les arquitectures de gestió i control de les xarxes tradicionals que no estan llestes per afrontar. Per acabar de descriure el context, la cinquena generació de tecnologia mòbil (5G) també presenta nous requisits de xarxa altament exigents, com la necessitat de connectar a la xarxa milers de milions de dispositius nous, dins el context de l’Internet de les coses (IOT), o les noves aplicacions d’ultra baixa latència (com ara la cirurgia a distància) i les comunicacions vehiculars. Se suposa que tots aquests nous serveis, juntament amb l’accés millorat a la xarxa de banda ampla, es lliuraran a través de la mateixa infraestructura de xarxa. Aquesta tesi doctoral proposa una visió holística dels recursos de xarxa i cloud, basada en els principis introduïts per Software Defined Networking (SDN), com la solució per al disseny de una arquitectura de gestió extrem a extrem per a escenaris de xarxa multi-capa, multi-domini i consistents en múltiples tecnologies de transport. Aquesta arquitectura de gestió i control de xarxes transport i recursos IT, ha de ser capaç d’oferir serveis d’extrem a extrem, des de les xarxes intra-DC fins a les xarxes d’accés dels clients i oferir a més virtualització dels recursos de la xarxa, obrint la porta a noves formes de segmentació a les xarxes de transport i la infrastructura de cloud, pels propers desplegaments de 5G. La primera contribució d’aquesta tesi doctoral consisteix en la validació de diferents arquitectures d’orquestració de xarxa basades en SDN capaces de millorar les solucions existents per a la gestió i control de xarxes de transport troncals multi-domini i multicapa. Aquests problemes (gestió de xarxes multicapa i multi-domini), han estat avaluats de manera incremental, mitjançant el disseny i l’avaluació experimental, en entorns de proves reals, de diferents arquitectures de control i gestió. Un dels principals troballes d’aquest treball ha estat la necessitat de dissenyar un model d’informació comú per a les interfícies de gestió de xarxes, capaç de descriure els recursos i serveis de la xarxes transport multicapa. En aquesta línia, el Protocol de Control Orchestration (COP, en les seves sigles en anglès) ha estat proposat en aquesta Tesi, com una primera contribució cap a una interfície de gestió de xarxa estàndard basada en els principis bàsics de SDN. A més, en aquesta tesi presentem una arquitectura innovadora capaç de coordinar la gestió de els recursos IT juntament amb les xarxes inter i intra-DC. L’aprovisionament i la migració de màquines virtuals juntament amb la reconfiguració dinàmica de la xarxa, ha estat demostrat amb èxit en una escala de temps factible. A més, l’arquitectura incorpora una plataforma per a l’execució d’algorismes d’optimització de recursos, capaços de resoldre diferents problemes d’assignació, com el desplegament òptim de Grafs de Màquines Virtuals (VMG) en diferents ubicacions de DC que minimitzen la assignació de recursos de xarxa entre DC. També es presenta una solució bàsica per a aquest problema, així com els resultats de probabilitat de bloqueig per a diferents càrregues de xarxa. La tercera contribució principal és el resultat dels dos anteriors. Amb una infraestructura de xarxa i cloud convergent, controlada i operada de manera conjunta, la visió holística de la xarxa permet l’aprovisionament sota demanda de "network slices" que consisteixen en subconjunts de recursos d’xarxa i cloud, dedicats per a diferents clients, sobre una infraestructura de Data Centers distribuïda i interconnectada per una xarxa de transport òptica. Els últims capítols d’aquesta tesi tracten sobre la gestió i organització de "network slices" per a xarxes 5G en funció dels components de control i administració dissenyats i desenvolupats en els capítols anteriors. El disseny d’una de les primeres arquitectures de "network slicing" i el desplegament d’un "slice" de xarxa 5G totalment operatiu en un Testbed real, és una de les principals contribucions d’aquesta tesi.Postprint (published version

Automatic provisioning in multi-domain software defined networking

Multi-domain Software Defined Networking (SDN) is the extension of the SDN paradigm to multi-domain networking and the interconnection of different administrative domains. By utilising SDN in the core telecommunication networks, benefits are found including improved traffic flow control, fast route updates and the potential for routing centralisation across domains. The Border Gateway Protocol (BGP) was designed three decades ago, and efforts to redesign interdomain routing that would include a replacement or upgrade to the existing BGP have yet to be realised. For the near real-time flow control provided by SDN, the domain boundary presents a challenge that is difficult to overcome when utilising existing protocols. Replacing the existing gateway mechanism, that provides routing updates between the different administrative domains, with a multi-domain centralised SDN-based solution may not be supported by the network operators, so it is a challenge to identify an approach that works within this constraint. In this research, BGP was studied and selected as the inter-domain SDN communication protocol, and it was used as the baseline protocol for a novel framework for automatic multi-domain SDN provisioning. The framework utilises the BGP UPDATE message with Communities and Extended Communities as the attributes for message exchange. A new application called Inter-Domain Provisioning of Routing Policy in ONOS (INDOPRONOS), for the framework implementation, was developed and tested. This application was built as an ONOS controller application, which collaborated with the existing ONOS SDN-IP application. The framework implementation was tested to verify the information exchange mechanism between domains, and it successfully carried out the provisioning actions that are triggered by that exchanged information. The test results show that the framework was successfully verified. The information carried inside the two attributes can successfully be transferred between domains, and it can be used to trigger INDOPRONOS to create and install new alternative intents to override the default intents of the ONOS controller. The intents installed by INDOPRONOS immediately change the route of the existing connection, which demonstrated that the correct request sent from the other domain, can carry out a modification in network settings inside a domain. Finally, the framework was tested using a bandwidth on demand use case. In this use case, a customer network administrator can immediately change the network service bandwidth which was provided by the service provider, without any intervention from the service provider administrator, based on an agreed-predefined configuration setting. This ability will provide benefits for both customer and service provider, in terms of customer satisfaction and network operations efficiency

An architecture for software defined wireless networking

Software defined networking, characterized by a clear separation of the control and data planes, is being adopted as a novel paradigm for wired networking. With SDN, network operators can run their infrastructure more efficiently, supporting faster deployment of new services while enabling key features such as virtualization. In this article, we adopt an SDN-like approach applied to wireless mobile networks that will not only benefit from the same features as in the wired case, but will also leverage on the distinct features of mobile deployments to push improvements even further. We illustrate with a number of representative use cases the benefits of the adoption of the proposed architecture, which is detailed in terms of modules, interfaces, and high-level signaling. We also review the ongoing standardization efforts, and discuss the potential advantages and weaknesses, and the need for a coordinated approach.The research leading to these results has been partly funded by the European Community's Seventh Framework Programme FP7/2007–2013 under grant agreement no. 317941-project iJOIN, http://www.ict-ijoin.eu/Publicad

Analyzing challenging aspects of IPv6 over IPv4

The exponential expansion of the Internet has exhausted the IPv4 addresses provided by IANA. The new IP edition, i.e. IPv6 introduced by IETF with new features such as a simplified packet header, a greater address space, a different address sort, improved encryption, powerful section routing, and stronger QoS. ISPs are slowly seeking to migrate from current IPv4 physical networks to new generation IPv6 networks. ‎The move from actual IPv4 to software-based IPv6 is very sluggish, since billions of computers across the globe use IPv4 addresses. The configuration and actions of IP4 and IPv6 protocols are distinct. Direct correspondence between IPv4 and IPv6 is also not feasible. In terms of the incompatibility problems, all protocols can co-exist throughout the transformation for a few years. Compatibility, interoperability, and stability are key concerns between IP4 and IPv6 protocols. After the conversion of the network through an IPv6, the move causes several issues for ISPs. The key challenges faced by ISPs are packet traversing, routing scalability, performance reliability, and protection. Within this study, we meticulously analyzed a detailed overview of all aforementioned issues during switching into ipv6 network

Virtual network function development for NG-PON Access Network Architecture

Dissertação de mestrado em Engenharia de Redes e Serviços TelemáticosThe access to Internet services on a large scale, high throughput and low latency has grown at a very high pace over time, with a growing demand for media content and applications increasingly oriented towards data consumption. This fact about the use of data at the edge of the network requires the Central Offices (CO) of telecommunication providers, to be pre pared to absorb these demands. COs generally offer data from various access methods, such as Passive Optical Network (PON) technologies, mobile networks, copper wired and oth ers. For each of these technologies there may be different manufacturers that support only their respective hardware and software solutions, although they all share different network resources and have management, configuration and monitoring tools (Fault, Configuration, Accounting, Performance, and Security management - FCAPS) similar, but being distinct and isolated from each other, which produces huge investment in Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) and can cause barriers to innovation. Such panora mas forced the development of more flexible, scalable solutions that share platforms and net work architectures that can meet this need and enable the evolution of networks. It is then proposed the architecture of Software-Defined Network (SDN) which has in its proposal to abstract the control plane from the data plane, in addition to the virtualization of several Net work Function Virtualization (NFV). The SDN architecture allows APIs and protocols such as Openflow, NETCONF / YANG, RESTCONF, gRPC and others to be used so that there is communication between the various hardware and software elements that compose the net work and consume network resources, such as services AAA, DHCP, routing, orchestration, management or various applications that may exist in this context. This work then aims at the development of a virtualized network function, namely a VNF in the context of network security to be integrated as a component of an architecture guided by the SDN paradigm applied to broadband networks, and also adherent to the architecture OB-BAA promoted by the Broadband Forum. Such OB-BAA architecture fits into the initia tive to modernize the Information Technology (IT) components of broadband networks, more specifically the Central Offices. With such development, it was intended to explore the con cepts of network security, such as the IEEE 802.1X protocol applied in NG-PON networks for authentication and authorization of new network equipment. To achieve this goal, the development of the applications was based on the Golang language combined with gRPC programmable interfaces for communication between the various elements of the architec ture. Network emulators were initially used, and then the components were ”containerized” and inserted in the Docker and Kubernetes virtualization frameworks. Finally, performance metrics were analyzed in the usage tests, namely computational resource usage metrics (CPU, memory and network I/O), in addition to the execution time of several processes performed by the developed applications.O acesso aos serviços de Internet em larga escala, alto débito e baixa latência têm crescido em um ritmo bastante elevado ao longo dos tempos, com uma demanda crescente por conteúdos de media e aplicações cada vez mais orientadas ao consumo de dados. Tal fato acerca da uti lização de dados na periferia da rede, obriga a que os Central Offices (CO) dos provedores de telecomunicações estejam preparados para absorver estas demandas. Os CO geralmente re cebem dados de diversos métodos de acesso, como tecnologias Passive Optical Network (PON), redes móveis, cabladas em cobre, entre outros. Para cada uma destas tecnologias pode haver diferentes fabricantes que suportam somente suas respetivas soluções de hardware e software, apesar de todas compartilharem diversos recursos de rede e possuírem ferramentas de gestão, configuração e monitoração (Fault-management, Configuration, Accounting, Performance e Segurança - FCAPS) similares, mas serem distintas e isoladas entre si, o que se traduz em um enorme investimento em Capital Expenditure (CAPEX) e Operational Expenditure (OPEX) e pode causar barreiras à inovação. Tais panoramas forçaram o desenvolvimento de soluções mais flexíveis, escaláveis e que compartilhem plataformas e arquiteturas de redes que pos sam suprir tal necessidade e possibilitar a evolução das redes. Propõe-se então a arquitetura de redes definidas por software (Software-Defined Network - SDN) que tem em sua proposta abstrair o plano de controle do plano de dados, além da virtualização de diversas funções de rede (Network Function Virtualization - NFV). A arquitetura SDN possibilita que API’s e pro tocolos como Openflow, NETCONF/YANG, RESTCONF, gRPC e outros, sejam utilizados para que haja comunicação entre os diversos elementos de hardware e software que estejam a compor a rede e a consumir recursos de redes, como serviços de AAA, DHCP, roteamento, orquestração, gestão ou diversas outras aplicações que possam existir neste contexto. Este trabalho visa então o desenvolvimento de uma função de rede virtualizada nomeada mente uma (Virtual Network Function - VNF) no âmbito de segurança de redes a ser integrada como um componente de uma arquitetura orientada pelo paradigma de SDN aplicado a re des de banda larga, e aderente também à arquitetura OB-BAA promovida pelo Broadband Fo rum. Tal arquitetura OB-BAA se enquadra na iniciativa de modernização dos componentes de Tecnologia da Informação (TI) das redes de banda larga, mais especificamente dos Cen tral Offices. Com tal desenvolvimento pretende-se explorar conceitos de segurança de redes, como o protocolo IEEE 802.1X aplicado em redes NG-PON para autenticação e autorização de novos equipamentos de rede. Para atingir tal objetivo, utilizou-se desenvolvimento de aplicações baseadas na linguagem Golang aliado com interfaces programáveis gRPC para comunicação entre os diversos elementos da arquitetura. Para emular tais componentes, utilizou-se inicialmente emuladores de rede, e em um segundo momento os componentes foram ”containerizados” e inseridos nos frameworks de virtualização Docker e Kubernetes.Por fim, foram analisadas métricas de desempenho nos testes executados, nomeadamente métricas de utilização de recursos computacionais (CPU, memória e tráfego de rede), além do tempo de execução de diversos processos desempenhados pelas aplicações desenvolvidas

Transmissão de video melhorada com recurso a SDN em ambientes baseados em cloud

The great technological development of informatics has opened the way for provisioning various services and new online-based entertainment services, which have expanded significantly after the increase in social media applications and the number of users. This significant expansion has posed an additional challenge to Internet Service Providers (ISP)s in terms of management for network, equipment and the efficiency of service delivery. New notions and techniques have been developed to offer innovative solutions such as SDN for network management, virtualization for optimal resource utilization and others like cloud computing and network function virtualization. This dissertation aims to manage live video streaming in the network automatically by adding a design architecture to the virtual network environment that helps to filter video packets from the remaining ones into a certain tunnel and this tunnel will be handled as a higher priority to be able to provide better service for customers. With the dedicated architecture, side by side, a monitoring application integrated into the system was used to detect the video packets and notify the SDN server to the existence of the video through the networkOs grandes avanços tecnológicos em informática abriram o caminho para o fornecimento de vários serviços e novos aplicações de entretenimento baseadas na web, que expandiram significativamente com a explosão no número de aplicações e utilizadores das redes sociais. Esta expansão significativa colocou desafios adicionais aos fornecedores de serviços de rede, em termos de gestão de rede, equipamento e a eficácia do fornecimento de serviços. Novas noções e técnicas foram desenvolvidas para oferecer soluções inovadoras, tais como redes definidas por software (SDN) para a gestão de rede, virtualização para a optimização da utilização dos recursos e outros, tais como a computação em nuvem e as funções de rede virtualizadas. Esta dissertação pretende gerir automaticamente a emissão de vídeo ao vivo na rede, através da adição de uma arquitetura ao ambiente de rede virtualizado, que auxilie a filtragem de pacotes de vídeo dos do restante tráfego, para um túnel específico, que será gerido com uma prioridade maior, capaz de fornecer melhor serviço aos clientes. Além do desenho da arquitectura, scripts de Python foram usados para detectar os pacotes de vídeo e injetar novas regras no controlador SDN que monitoriza o tráfego ao longo da rede.Mestrado em Engenharia de Computadores e Telemátic