A study into scalable transport networks for IoT deployment

The growth of the internet towards the Internet of Things (IoT) has impacted the way we live. Intelligent (smart) devices which can act autonomously has resulted in new applications for example industrial automation, smart healthcare systems, autonomous transportation to name just a few. These applications have dramatically improved the way we live as citizens. While the internet is continuing to grow at an unprecedented rate, this has also been coupled with the growing demands for new services e.g. machine-to machine (M2M) communications, smart metering etc. Transmission Control Protocol/Internet Protocol (TCP/IP) architecture was developed decades ago and was not prepared nor designed to meet these exponential demands. This has led to the complexity of the internet coupled with its inflexible and a rigid state. The challenges of reliability, scalability, interoperability, inflexibility and vendor lock-in amongst the many challenges still remain a concern over the existing (traditional) networks. In this study, an evolutionary approach into implementing a "Scalable IoT Data Transmission Network" (S-IoT-N) is proposed while leveraging on existing transport networks. Most Importantly, the proposed evolutionary approach attempts to address the above challenges by using open (existing) standards and by leveraging on the (traditional/existing) transport networks. The Proof-of-Concept (PoC) of the proposed S-IoT-N is attempted on a physical network testbed and is demonstrated along with basic network connectivity services over it. Finally, the results are validated by an experimental performance evaluation of the PoC physical network testbed along with the recommendations for improvement and future work

A survey of Virtual Private LAN Services (VPLS): Past, present and future

Virtual Private LAN services (VPLS) is a Layer 2 Virtual Private Network (L2VPN) service that has gained immense popularity due to a number of its features, such as protocol independence, multipoint-to-multipoint mesh connectivity, robust security, low operational cost (in terms of optimal resource utilization), and high scalability. In addition to the traditional VPLS architectures, novel VPLS solutions have been designed leveraging new emerging paradigms, such as Software Defined Networking (SDN) and Network Function Virtualization (NFV), to keep up with the increasing demand. These emerging solutions help in enhancing scalability, strengthening security, and optimizing resource utilization. This paper aims to conduct an in-depth survey of various VPLS architectures and highlight different characteristics through insightful comparisons. Moreover, the article discusses numerous technical aspects such as security, scalability, compatibility, tunnel management, operational issues, and complexity, along with the lessons learned. Finally, the paper outlines future research directions related to VPLS. To the best of our knowledge, this paper is the first to furnish a detailed survey of VPLS.University College DublinAcademy of Finlan

Intelligent based Packet Scheduling Scheme using Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) Technology for 5G. Design and Investigation of Bandwidth Management Technique for Service-Aware Traffic Engineering using Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) for 5G

Multi-Protocol Label Switching (MPLS) makes use of traffic engineering (TE) techniques and a variety of protocols to establish pre-determined highly efficient routes in Wide Area Network (WAN). Unlike IP networks in which routing decision has to be made through header analysis on a hop-by-hop basis, MPLS makes use of a short bit sequence that indicates the forwarding equivalence class (FEC) of a packet and utilises a predefined routing table to handle packets of a specific FEC type. Thus header analysis of packets is not required, resulting in lower latency. In addition, packets of similar characteristics can be routed in a consistent manner. For example, packets carrying real-time information can be routed to low latency paths across the networks. Thus the key success to MPLS is to efficiently control and distribute the bandwidth available between applications across the networks. A lot of research effort on bandwidth management in MPLS networks has already been devoted in the past. However, with the imminent roll out of 5G, MPLS is seen as a key technology for mobile backhaul. To cope with the 5G demands of rich, context aware and multimedia-based user applications, more efficient bandwidth management solutions need to be derived. This thesis focuses on the design of bandwidth management algorithms, more specifically QoS scheduling, in MPLS network for 5G mobile backhaul. The aim is to ensure the reliability and the speed of packet transfer across the network. As 5G is expected to greatly improve the user experience with innovative and high quality services, users’ perceived quality of service (QoS) needs to be taken into account when deriving such bandwidth management solutions. QoS expectation from users are often subjective and vague. Thus this thesis proposes the use of fuzzy logic based solution to provide service aware and user-centric bandwidth management in order to satisfy requirements imposed by the network and users. Unfortunately, the disadvantage of fuzzy logic is scalability since dependable fuzzy rules and membership functions increase when the complexity of being modelled increases. To resolve this issue, this thesis proposes the use of neuro-fuzzy to solicit interpretable IF-THEN rules.The algorithms are implemented and tested through NS2 and Matlab simulations. The performance of the algorithms are evaluated and compared with other conventional algorithms in terms of average throughput, delay, reliability, cost, packet loss ratio, and utilization rate. Simulation results show that the neuro-fuzzy based algorithm perform better than fuzzy and other conventional packet scheduling algorithms using IP and IP over MPLS technologies.Tertiary Education Trust Fund (TETFUND

High-fidelity rendering on shared computational resources

The generation of high-fidelity imagery is a computationally expensive process and parallel computing has been traditionally employed to alleviate this cost. However, traditional parallel rendering has been restricted to expensive shared memory or dedicated distributed processors. In contrast, parallel computing on shared resources such as a computational or a desktop grid, offers a low cost alternative. But, the prevalent rendering systems are currently incapable of seamlessly handling such shared resources as they suffer from high latencies, restricted bandwidth and volatility. A conventional approach of rescheduling failed jobs in a volatile environment inhibits performance by using redundant computations. Instead, clever task subdivision along with image reconstruction techniques provides an unrestrictive fault-tolerance mechanism, which is highly suitable for high-fidelity rendering. This thesis presents novel fault-tolerant parallel rendering algorithms for effectively tapping the enormous inexpensive computational power provided by shared resources. A first of its kind system for fully dynamic high-fidelity interactive rendering on idle resources is presented which is key for providing an immediate feedback to the changes made by a user. The system achieves interactivity by monitoring and adapting computations according to run-time variations in the computational power and employs a spatio-temporal image reconstruction technique for enhancing the visual fidelity. Furthermore, algorithms described for time-constrained offline rendering of still images and animation sequences, make it possible to deliver the results in a user-defined limit. These novel methods enable the employment of variable resources in deadline-driven environments

Advanced techniques for multicast service provision in core transport networks

Although the network-based multicast service is the optimal way to support of a large variety of popular applications such as high-definition television (HDTV), videoon- demand (VoD), virtual private LAN service (VPLS), grid computing, optical storage area networks (O-SAN), video conferencing, e-learning, massive multiplayer online role-playing games (MMORPG), networked virtual reality, etc., there are a number of technological and operational reasons that prevents a wider deployment. This PhD work addresses this problem in the context of core transport network, by proposing and analyzing new cost-effective and scalable techniques to support multicast both at the Optical layer and at the Network layer (MPLS-IP networks). In the Optical layer, in particular in Wavelength Division Multiplexing (WDM) Optical Circuit Switched networks, current multicast-capable OXC node designs are of a great complexity and have high attenuation levels, mainly because of the required signal splitting operation plus the traversal of a complex switching stage. This makes multi-point support rarely included in commercial OXC nodes. Inspired in previous works in the literature, we propose a novel architecture that combines the best of splitting and tap-and-continue (TaC), called 2-STC (2-split-tap-and-continue) in the framework of integrated optics. A 2-STC OXC node is a flexible design capable of tapping and splitting over up to two outgoing links in order to obtain lower end-to-end latency than in TaC and an improved power budget distribution over split-and-delivery (SaD) designs. Another advantage of this architecture is its simplicity and the reduced number of components required, scaling well even for implementations of the node with many input/output ports. Extensive simulations show that the binary split (2-split) is quite enough for most real-life core network topologies scenarios, since the average node degree is usually between 3 and 4. A variant of this design, called 2-STCg, for making the node capable of optical traffic grooming (i.e. accommodation of low-speed demands into wavelength-links) is also presented. At the Network layer, one of the main reasons that hinder multicast deployment is the high amount of forwarding state information required in core routers, especially when a large number of medium/small-sized multicast demands arrive to the core network, because the state data that needs to be kept at intermediate core routers grows proportionally to the number of multicast demands. In this scenario, we study the aggregation of multicast demands into shared distribution trees, providing a set of techniques to observe the trade-off between bandwidth and state information. This study is made in the context of MPLS VPN-based networks, with the aggregation of multicast VPNs in different real network scenarios and using novel heuristics for aggregation. Still, the main problem of aggregation is the high percentage of wasted bandwidth that depends mainly on the amount of shared trees used. On the other hand, recent works have brought back Bloom filters as an alternative for multicast forwarding. In this approach the packet header contains a Bloom filter that is evaluated at each hop for matching with the corresponding outgoing link ID. Although this approach is claimed to be stateless, it presents serious drawbacks due to false positives, namely important forwarding anomalies (duplicated flows, packet storms and loops) and the header overhead. In order to solve these drawbacks we propose D-MPSS (Depth-Wise Multi-Protocol Stateless Switching). This technique makes use of a stack of Bloom filters instead of a single one for all the path/tree, each one including only the links of a given depth of the tree. Analytical studies and simulations show that our approach reduces the forwarding anomalies present in similar state-of-the-art techniques, achieving in most network scenarios a forwarding efficiency (useful traffic) greater than 95%. Finally, we study the possibility of using tree aggregation and Bloom filters together, and propose a set of techniques grouped as H-ABF techniques (hybrid aggregation - Bloom filter-based forwarding), which improve D-MPSS and other previously proposed techniques, practically eliminating the forwarding loops and increasing the forwarding efficiency up to more than 99% in most network scenarios. -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Aunque el servicio de multidifusión (multicast) basado en redes es la mejor manera de dar soporte a una gran variedad de aplicaciones populares como la televisión de alta definición (HDTV), el video bajo demanda (VoD), el servicio de LAN privadas virtuales (VPLS), la computación grid, las redes de área de almacenamiento óptico (O-SAN), la videoconferencia, la educación a distancia, los juegos masivos de rol en línea de múltiples jugadores (MMORPG), la realidad virtual en red, etc., hay varias razones tecnológicas y operacionales que le impiden un mayor despliegue. Esta tesis doctoral aborda este problema en el contexto de las redes troncales de transporte, proponiendo y analizando técnicas de bajo coste y escalables para dar soporte al multicast tanto para la capa óptica como para la capa de red (redes MPLS-IP). En la capa óptica, en particular en las redes ópticas conmutadas por circuitos con multiplexación de longitud de onda (WDM), los diseños de nodos OXC con capacidades multicast muestran una gran complejidad y altos niveles de atenuación, principalmente debido a la necesaria operación de división de la señal, además del paso de ella a través de una compleja fase de conmutación. Esto hace que el soporte multi-punto sea raramente incluido en los nodos OXC comerciales. Inspirados en trabajos previos de la literatura, proponemos una novedosa arquitectura que combina lo mejor de dividir (splitting) y tap-y-continuar (TaC), llamado 2-STC (2-split-tapand- continue) en el marco de trabajo de la óptica integrada. Un nodo OXC 2-STC es un diseño flexible capaz de hacer tapping (tomar una pequeña muestra de la señal) y dividir la señal hacia un máximo de dos enlaces de salida, con el fin de obtener una menor latencia terminal-a-terminal que en TaC y una mejorada distribución de la disponibilidad de potencia por encima de los diseños split-and-delivery (SaD). Otra ventaja de esta arquitectura es su simplicidad y el número reducido de componentes requerido, escalando bien para las implementaciones del nodo con muchos puertos de entrada/salida. Extensas simulaciones muestran que la división binaria (2-split) es prácticamente suficiente para la mayoría de las topologías de redes de transporte en la vida real, debido a que el grado promedio de los nodos es usualmente 3 y 4. Una variante de este diseño, llamada 2-STCg, para hacer el nodo capaz de realizar grooming (es decir, la capacidad de acomodar demandas de menor velocidad en longitudes de onda - enlaces) de tráfico óptico, es también presentada. En la capa de red, una de las principales razones que obstaculizan el despliegue del multicast es la gran cantidad de información del estado de reenvío requerida en los enrutadores de la red de transporte, especialmente cuando un gran número de demandas multicast de tamaño mediano/pequeño llegan a la red de transporte, ya que los datos de estado a ser almacenados en los enrutadores crecen proporcionalmente con el número de demandas multicast. En este escenario, estudiamos la agregación de demandas multicast en árboles de distribución, proporcionando un conjunto de técnicas para observar el equilibrio entre el ancho de banda y la información de estado. Este estudio está hecho en el contexto de las redes basadas en redes privadas virtuales (VPN) MPLS, con la agregación de VPNs multicast en distintos escenarios de redes reales y utilizando nuevos heurísticos para la agregación. Aún así, el principal problema de la agregación es el alto porcentaje de ancho de banda desperdiciado que depende principalmente de la cantidad de árboles compartidos usados. Por otro lado, trabajos recientes han vuelto a traer a los filtros de Bloom como una alternativa para realizar el reenvío multicast. En esta aproximación la cabecera del paquete contiene un filtro de Bloom que es evaluado en cada salto para emparejarlo con el identificador del enlace de salida correspondiente. Aunque se afirma que esta solución no utiliza información de estado, presenta serias desventajas debido a los falsos positivos, esto es, anomalías de reenvío importantes (flujos duplicados, tormentas de paquetes y bucles) y gasto de ancho de banda por la cabecera de los paquetes. Para poder resolver estos problemas proponemos D-MPSS (Depth- Wise Multi-Protocol Stateless Switching). Esta técnica hace uso de una pila de filtros de Bloom en lugar de uno sólo para todo el camino/árbol, incluyendo cada uno sólo los enlaces de una determinada profundidad del árbol. Estudios analíticos y simulaciones demuestran que nuestra propuesta reduce los anomalías de reenvío presentes en otras técnicas similares del estado del arte, alcanzando en la mayoría de escenarios reales una eficiencia de reenvío (tráfico útil) mayor que 95%. Finalmente, estudiamos la posibilidad de usar agregación de árboles y filtros de Bloom juntos, y proponemos un conjunto de técnicas agrupadas como técnicas HABF (hybrid aggregation - Bloom filter-based forwarding), que mejoran D-MPSS y las otras técnicas propuestas previamente, eliminando prácticamente los bucles e incrementando la eficiencia de reenvío hasta más de un 99% en la mayoría de los escenarios de redes

An outright open source approach for simple and pragmatic internet eXchange

L'Internet, le réseaux des réseaux, est indispensable à notre vie moderne et mondialisée et en tant que ressource publique il repose sur l'inter opérabilité et la confiance. Les logiciels libres et open source jouent un rôle majeur pour son développement. Les points d'échange Internet (IXP) où tous les opérateurs de type et de taille différents peuvent s'échanger du trafic sont essentiels en tant que lieux d'échange neutres et indépendants. Le service fondamental offert par un IXP est une fabrique de commutation de niveau 2 partagée. Aujourd'hui les IXP sont obligés d'utiliser des technologies propriétaires pour leur fabrique de commutations. Bien qu'une fabrique de commutations de niveau 2 se doit d'être une fonctionnalité de base, les solutions actuelles ne répondent pas correctement aux exigences des IXPs. Cette situation est principalement dûe au fait que les plans de contrôle et de données sont intriqués sans possibilités de programmer finement le plan de commutation. Avant toute mise en œuvre, il est primordial de tester chaque équipement afin de vérifier qu'il répond aux attentes mais les solutions de tests permettant de valider les équipements réseaux sont toutes non open source, commerciales et ne répondent pas aux besoins techniques d'indépendance et de neutralité. Le "Software Defined Networking" (SDN), nouveau paradigme découplant les plans de contrôle et de données utilise le protocole OpenFlow qui permet de programmer le plan de commutation Ethernet haute performance. Contrairement à tous les projets de recherches qui centralisent la totalité du plan de contrôle au dessus d'OpenFlow, altérant la stabilité des échanges, nous proposons d'utiliser OpenFlow pour gérer le plan de contrôle spécifique à la fabrique de commutation. L'objectif principal de cette thèse est de proposer "Umbrella", fabrique de commutation simple et pragmatique répondant à toutes les exigences des IXPs et en premier lieu à la garantie d'indépendance et de neutralité des échanges. Dans la première partie, nous présentons l'architecture "Umbrella" en détail avec l'ensemble des tests et validations démontrant la claire séparation du plan de contrôle et du plan de données pour augmenter la robustesse, la flexibilité et la fiabilité des IXPs. Pour une exigence d'autonomie des tests nécessaires pour les IXPs permettant l'examen de la mise en œuvre d'Umbrella et sa validation, nous avons développé l'"Open Source Network Tester" (OSNT), un système entièrement open source "hardware" de génération et de capture de trafic. OSNT est le socle pour l"OpenFLow Operations Per Second Turbo" (OFLOPS Turbo), la plate-forme d'évaluation de commutation OpenFlow. Le dernier chapitre présente le déploiement de l'architecture "Umbrella" en production sur un point d'échange régional. Les outils de test que nous avons développés ont été utilisés pour vérifier les équipements déployés en production. Ce point d'échange, stable depuis maintenant un an, est entièrement géré et contrôlé par une seule application Web remplaçant tous les systèmes complexes et propriétaires de gestion utilisés précédemment.In almost everything we do, we use the Internet. The Internet is indispensable for our today's lifestyle and to our globalized financial economy. The global Internet traffic is growing exponentially. IXPs are the heart of Internet. They are highly valuable for the Internet as neutral exchange places where all type and size of autonomous systems can "peer" together. The IXPs traffic explode. The 2013 global Internet traffic is equivalent with the largest european IXP today. The fundamental service offer by IXP is a shared layer2 switching fabric. Although it seems a basic functionality, today solutions never address their basic requirements properly. Today networks solutions are inflexible as proprietary closed implementation of a distributed control plane tight together with the data plane. Actual network functions are unmanageable and have no flexibility. We can understand how IXPs operators are desperate reading the EURO-IX "whishlist" of the requirements who need to be implemented in core Ethernet switching equipments. The network vendor solutions for IXPs based on MPLS are imperfect readjustment. SDN is an emerging paradigm decoupling the control and data planes, on opening high performance forwarding plane with OpenFlow. The aims of this thesis is to propose an IXP pragmatic Openflow switching fabric, addressing the critical requirements and bringing more flexibility. Transparency is better for neutrality. IXPs needs a straightforward more transparent layer2 fabric where IXP participants can exchange independently their traffic. Few SDN solutions have been presented already but all of them are proposing fuzzy layer2 and 3 separation. For a better stability not all control planes functions can be decoupled from the data plane. As other goal statement, networking testing tools are essential for qualifying networking equipment. Most of them are software based and enable to perform at high speed with accuracy. Moreover network hardware monitoring and testing being critical for computer networks, current solutions are both extremely expensive and inflexible. The experience in deploying Openflow in production networks has highlight so far significant limitations in the support of the protocol by hardware switches. We presents Umbrella, a new SDN-enabled IXP fabric architecture, that aims at strengthening the separation of control and data plane to increase both robustness, flexibility and reliability of the exchange. Umbrella abolish broadcasting with a pseudo wire and segment routing approach. We demonstrated for an IXP fabric not all the control plane can be decoupled from the date plane. We demonstrate Umbrella can scale and recycle legacy non OpenFlow core switch to reduce migration cost. Into the testing tools lacuna we launch the Open Source Network Tester (OSNT), a fully open-source traffic generator and capture system. Additionally, our approach has demonstrated lower-cost than comparable commercial systems while achieving comparable levels of precision and accuracy; all within an open-source framework extensible with new features to support new applications, while permitting validation and review of the implementation. And we presents the integration of OpenFLow Operations Per Second (OFLOPS), an OpenFlow switch evaluation platform, with the OSNT platform, a hardware-accelerated traffic generation and capturing platform. What is better justification than a real deployment ? We demonstrated the real flexibility and benefit of the Umbrella architecture persuading ten Internet Operators to migrate the entire Toulouse IXP. The hardware testing tools we have developed have been used to qualify the hardware who have been deployed in production. The TouIX is running stable from a year. It is fully managed and monitored through a single web application removing all the legacy complex management systems

Ethernet Networks for Real-Time Use in the ATLAS Experiment

Ethernet became today's de-facto standard technology for local area networks. Defined by the IEEE 802.3 and 802.1 working groups, the Ethernet standards cover technologies deployed at the first two layers of the OSI protocol stack. The architecture of modern Ethernet networks is based on switches. The switches are devices usually built using a store-and-forward concept. At the highest level, they can be seen as a collection of queues and mathematically modelled by means of queuing theory. However, the traffic profiles on modern Ethernet networks are rather different from those assumed in classical queuing theory. The standard recommendations for evaluating the performance of network devices define the values that should be measured but do not specify a way of reconciling these values with the internal architecture of the switches. The introduction of the 10 Gigabit Ethernet standard provided a direct gateway from the LAN to the WAN by the means of the WAN PHY. Certain aspects related to the actual use of WAN PHY technology were vaguely defined by the standard. The ATLAS experiment at CERN is scheduled to start operation at CERN in 2007. The communication infrastructure of the Trigger and Data Acquisition System will be built using Ethernet networks. The real-time operational needs impose a requirement for predictable performance on the network part. In view of the diversity of the architectures of Ethernet devices, testing and modelling is required in order to make sure the full system will operate predictably. This thesis focuses on the testing part of the problem and addresses issues in determining the performance for both LAN and WAN connections. The problem of reconciling results from measurements to architectural details of the switches will also be tackled. We developed a scalable traffic generator system based on commercial-off-the-shelf Gigabit Ethernet network interface cards. The generator was able to transmit traffic at the nominal Gigabit Ethernet line rate for all frame sizes specified in the Ethernet standard. The calculation of latency was performed with accuracy in the range of +/- 200 ns. We indicate how certain features of switch architectures may be identified through accurate throughput and latency values measured for specific traffic distributions. At this stage, we present a detailed analysis of Ethernet broadcast support in modern switches. We use a similar hands-on approach to address the problem of extending Ethernet networks over long distances. Based on the 1 Gbit/s traffic generator used in the LAN, we develop a methodology to characterise point-to-point connections over long distance networks. At higher speeds, a combination of commercial traffic generators and high-end servers is employed to determine the performance of the connection. We demonstrate that the new 10 Gigabit Ethernet technology can interoperate with the installed base of SONET/SDH equipment through a series of experiments on point-to-point circuits deployed over long-distance network infrastructure in a multi-operator domain. In this process, we provide a holistic view of the end-to-end performance of 10 Gigabit Ethernet WAN PHY connections through a sequence of measurements starting at the physical transmission layer and continuing up to the transport layer of the OSI protocol stack