Software Defined Applications in Cellular and Optical Networks

abstract: Small wireless cells have the potential to overcome bottlenecks in wireless access through the sharing of spectrum resources. A novel access backhaul network architecture based on a Smart Gateway (Sm-GW) between the small cell base stations, e.g., LTE eNBs, and the conventional backhaul gateways, e.g., LTE Servicing/Packet Gateways (S/P-GWs) has been introduced to address the bottleneck. The Sm-GW flexibly schedules uplink transmissions for the eNBs. Based on software defined networking (SDN) a management mechanism that allows multiple operator to flexibly inter-operate via multiple Sm-GWs with a multitude of small cells has been proposed. This dissertation also comprehensively survey the studies that examine the SDN paradigm in optical networks. Along with the PHY functional split improvements, the performance of Distributed Converged Cable Access Platform (DCCAP) in the cable architectures especially for the Remote-PHY and Remote-MACPHY nodes has been evaluated. In the PHY functional split, in addition to the re-use of infrastructure with a common FFT module for multiple technologies, a novel cross functional split interaction to cache the repetitive QAM symbols across time at the remote node to reduce the transmission rate requirement of the fronthaul link has been proposed.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

A Survey on the Path Computation Element (PCE) Architecture

Quality of Service-enabled applications and services rely on Traffic Engineering-based (TE) Label Switched Paths (LSP) established in core networks and controlled by the GMPLS control plane. Path computation process is crucial to achieve the desired TE objective. Its actual effectiveness depends on a number of factors. Mechanisms utilized to update topology and TE information, as well as the latency between path computation and resource reservation, which is typically distributed, may affect path computation efficiency. Moreover, TE visibility is limited in many network scenarios, such as multi-layer, multi-domain and multi-carrier networks, and it may negatively impact resource utilization. The Internet Engineering Task Force (IETF) has promoted the Path Computation Element (PCE) architecture, proposing a dedicated network entity devoted to path computation process. The PCE represents a flexible instrument to overcome visibility and distributed provisioning inefficiencies. Communications between path computation clients (PCC) and PCEs, realized through the PCE Protocol (PCEP), also enable inter-PCE communications offering an attractive way to perform TE-based path computation among cooperating PCEs in multi-layer/domain scenarios, while preserving scalability and confidentiality. This survey presents the state-of-the-art on the PCE architecture for GMPLS-controlled networks carried out by research and standardization community. In this work, packet (i.e., MPLS-TE and MPLS-TP) and wavelength/spectrum (i.e., WSON and SSON) switching capabilities are the considered technological platforms, in which the PCE is shown to achieve a number of evident benefits

Network Virtualization Over Elastic Optical Networks: A Survey of Allocation Algorithms

Network virtualization has emerged as a paradigm for cloud computing services by providing key functionalities such as abstraction of network resources kept hidden to the cloud service user, isolation of different cloud computing applications, flexibility in terms of resources granularity, and on‐demand setup/teardown of service. In parallel, flex‐grid (also known as elastic) optical networks have become an alternative to deal with the constant traffic growth. These advances have triggered research on network virtualization over flex‐grid optical networks. Effort has been focused on the design of flexible and virtualized devices, on the definition of network architectures and on virtual network allocation algorithms. In this chapter, a survey on the virtual network allocation algorithms over flexible‐grid networks is presented. Proposals are classified according to a taxonomy made of three main categories: performance metrics, operation conditions and the type of service offered to users. Based on such classification, this work also identifies open research areas as multi‐objective optimization approaches, distributed architectures, meta‐heuristics, reconfiguration and protection mechanisms for virtual networks over elastic optical networks

On the resource abstraction, partitioning and composition for virtual GMPLS-controlled multi-layer optical networks

Virtual optical networking supports the dynamic provisioning of dedicated networks over the same network infrastructure, which has received a lot of attention by network providers. The stringent network requirements (e.g., Quality of Service -QoS-, Service Level Agreement -SLA-, dynamicity) of the emerging high bandwidth and dynamic applications such as high-definition video streaming (e.g., telepresence, television, remote surgery, etc.), and cloud computing (e.g., real-time data backup, remote desktop, etc.) can be supported by the deployment of dynamic infrastructure services to build ad-hoc Virtual Optical Networks (VON), which is known as Infrastructure as a Service (IaaS). Future Internet should support two separate entities: infrastructure providers (who manage the physical infrastructure) and service providers (who deploy network protocols and offer end-to-end services). Thus, network service providers shall request, on a per-need basis, a dedicated and application-specific VON and have full control over it. Optical network virtualization technologies allow the partitioning/composition of the network infrastructure (i.e., physical optical nodes and links) into independent virtual resources, adopting the same functionality as the physical resource. The composition of these virtual resources (i.e., virtual optical nodes and links) allows the deployment of multiple VONs. A VON must be composed of not only a virtual transport plane but also of a virtual control plane, with the purpose of providing the required independent and full control functionalities (i.e., automated connection provisioning and recovery (protection/restauration), traffic engineering (e.g., QoS, SLA), etc.). This PhD Thesis focuses on optical network virtualization, with three main objectives. The first objective consists on the design, implementation and evaluation of an architecture and the necessary protocols and interfaces for the virtualization of a Generalized Multi-Protocol Label Switching (GMPLS) controlled Wavelength Switched Optical Network (WSON) and the introduction of a resource broker for dynamic virtual GMPLS-controlled WSON infrastructure services, whose task is to dynamically deploy VONs from service provider requests. The introduction of a resource broker implies the need for virtual resource management and allocation algorithms for optimal usage of the shared physical infrastructure. Also, the deployment of independent virtual GMPLS control plane on top of each VON shall be performed by the resource broker. This objective also includes the introduction of optical network virtualization for Elastic Optical Networks (EON). The second objective is to design, implement and experimentally evaluate a system architecture for deploying virtual GMPLS-controlled Multi-Protocol Label Switching Transport Profile (MPLS-TP) networks over a shared WSON. With this purpose, this PhD Thesis also focuses on the design and development of MPLS-TP nodes which are deployed on the WSON of the ADRENALINE Testbed at CTTC premises. Finally, the third objective is the composition of multiple virtual optical networks with heterogeneous control domains (e.g., GMPLS, OpenFlow). A multi-domain resource broker has been designed, implemented and evaluated.La gestió de xarxes òptiques virtuals permet la provisió dinàmica de xarxes dedicades a sobre la mateixa infraestructura de xarxa i ha cridat molt l’atenció als proveïdors de xarxes. Els requisits de xarxa (per exemple la qualitat de servei, els acords de nivell de servei o la dinamicitat) són cada cop més astringents per a les aplicacions emergents d'elevat ample de banda i dinàmiques, que inclouen per exemple la reproducció en temps real de vídeo d'alta definició (telepresència, televisió, telemedicina) i serveis d’informàtica en núvol (còpies de seguretat en temps real, escriptori remot). Aquests requisits poden ser assolits a través del desplegament de serveis de infraestructura dinàmics per construir xarxes òptiques virtuals (VON, en anglès), fet que és conegut com a infraestructura com a servei (IaaS). La internet del futur hauria de suportar dos entitats diferenciades: els proveïdors d'infraestructures (responsables de gestionar la infraestructura física), i els proveïdors de serveis (responsables dels protocols de xarxa i d'oferir els serveis finals). D'aquesta forma els proveïdors de serveis podrien sol•licitar i gestionar en funció de les necessitats xarxes òptiques virtuals dedicades i específiques per les aplicacions. Les tecnologies de virtualització de xarxes òptiques virtuals permeten la partició i composició de infraestructura de xarxa (nodes i enllaços òptics) en recursos virtuals independents que adopten les mateixes funcionalitats que els recursos físics. La composició d'aquests recursos virtuals (nodes i enllaços òptics virtuals) permet el desplegament de múltiples VONs. Una VON no sols està composada per un pla de transport virtual, sinó també per un pla de control virtual, amb l'objectiu d'incorporar les funcionalitats necessàries a la VON (provisió de connexions automàtiques i recuperació (protecció/restauració), enginyeria de tràfic, etc.). Aquesta tesis es centra en la virtualització de xarxes òptiques amb tres objectius principals. El primer objectiu consisteix en el disseny, implementació i avaluació de l'arquitectura i els protocols i interfícies necessaris per la virtualització de xarxes encaminades a través de la longitud d'ona i controlades per GMPLS. També inclou la introducció d'un gestor de recursos per desplegar xarxes òptiques virtuals de forma dinàmica. La introducció d'aquest gestor de recursos implica la necessitat d'una gestió dels recursos virtuals i d’algoritmes d’assignació de recursos per a la utilització òptima dels recursos físics. A més el gestor de recursos ha de ser capaç del desplegament dels recursos assignats, incloent un pla de control GMPLS virtual independent per a cada VON desplegada. Finalment, aquest objectiu inclou la introducció de mecanismes de virtualització per a xarxes elàstiques òptiques (EON, en anglès). El segon objectiu és el disseny, la implementació i l’avaluació experimental d'una arquitectura de sistema per oferir xarxes MPLS-TP virtuals controlades per GMPLS sobre una infraestructura i WSON compartida. Per això, aquesta tesis també es centra en el disseny i desenvolupament d'un node MPLS-TP que ha estat desplegat al demostrador ADRENALINE, al CTTC. Finalment, el tercer objectiu és la composició de múltiples xarxes òptiques virtuals en dominis de control heterogenis (GMPLS i OpenFlow). Un gestor de recursos multi-domini ha estat dissenyat, implementat i avaluat.La gestión de redes ópticas virtuales permite la provisión dinámica de redes dedicadas encima la misma infraestructura de red y ha llamado mucho la atención a los proveedores de redes. Los requisitos de red (por ejemplo la calidad de servicio, los acuerdos de nivel de servicio o la dinamicidad) son cada vez más estringentes para las aplicaciones emergentes de elevado ancho de banda y dinámicas, que incluyen por ejemplo la reproducción en tiempo real de vídeo de alta definición (telepresencia, televisión, telemedicina) y servicios de computación en la nube (copias de seguridad en tiempo real, escritorio remoto). Estos requisitos pueden ser logrados a través del despliegue de servicios de infraestructura dinámicos para construir redes ópticas virtuales (VON, en inglés), hecho que es conocido como infraestructura como servicio (IaaS). La internet del futuro tendrá que soportar dos entidades diferenciadas: los proveedores de infraestructuras (responsables de gestionar la infraestructura física), y los proveedores de servicios (responsables de los protocolos de red y de ofrecer los servicios finales). De esta forma los proveedores de servicios podrán solicitar y gestionar en función de las necesitados redes ópticas virtuales dedicadas y específicas por las aplicaciones. Las tecnologías de virtualización de redes ópticas virtuales permiten la partición y composición de infraestructura de red (nodos y enlaces ópticos) en recursos virtuales independientes que adoptan las mismas funcionalidades que los recursos físicos. La composición de estos recursos virtuales (nodos y enlaces ópticos virtuales) permite el despliegue de múltiples VONs. Una VON no sólo está compuesta por un plan de transporte virtual, sino también por un plan de control virtual, con el objetivo de incorporar las funcionalidades necesarias a la VON (provisión de conexiones automáticas y recuperación (protección/restauración), ingeniería de tráfico, etc.). Esta tesis se centra en la virtualización de redes ópticas con tres objetivos principales. El primer objetivo consiste en el diseño, implementación y evaluación de la arquitectura y los protocolos e interfaces necesarios por la virtualización de redes encaminadas a través de la longitud de ola y controladas por GMPLS. También incluye la introducción de un gestor de recursos para desplegar redes ópticas virtuales de forma dinámica. La introducción de este gestor de recursos implica la necesidad de una gestión de los recursos virtuales y de algoritmos de asignación de recursos para la utilización óptima de los recursos físicos. Además el gestor de recursos tiene que ser capaz del despliegue de los recursos asignados, incluyendo un plan de control GMPLS virtual independiente para cada VON desplegada. Finalmente, este objetivo incluye la introducción de mecanismos de virtualización para redes elásticas ópticas (EON, en inglés). El segundo objetivo es el diseño, la implementación y la evaluación experimental de una arquitectura de sistema para ofrecer redes MPLS-TP virtuales controladas por GMPLS sobre una infraestructura WSON compartida. Por eso, esta tesis también se centra en el diseño y desarrollo de un nodo MPLS-TP que ha sido desplegado al demostrador ADRENALINE, en el CTTC. Finalmente, el tercer objetivo es la composición de múltiples redes ópticas virtuales en dominios de control heterogéneos (GMPLS y OpenFlow). Un gestor de recursos multi-dominio ha sido diseñado, implementado y evaluado

Next Generation Flexible and Cognitive Heterogeneous Optical Networks:Supporting the Evolution to the Future Internet

Optical networking is the cornerstone of the Future Internet as it provides the physical infrastructure of the core backbone networks. Recent developments have enabled much better quality of service/experience for the end users, enabled through the much higher capacities that can be supported. Furthermore, optical networking developments facilitate the reduction of complexity of operations at the IP layer and therefore reduce the latency of the connections and the expenditures to deploy and operate the networks. New research directions in optical networking promise to further advance the capabilities of the Future Internet. In this book chapter, we highlight the latest activities of the optical networking community and in particular what has been the focus of EU funded research. The concepts of flexible and cognitive optical networks are introduced and their key expected benefits are highlighted. The overall framework envisioned for the future cognitive flexible optical networks are introduced and recent developments are presented

Software‐Defined Optical Networking (SDON): Principles and Applications

Featured by the advantages of high capacity, long transmission distance, and low energy consumption, optical network has been deployed widely as the most important infrastructure for backbone transport network. With the development of Internet, datacenter has become the popular infrastructure for cloud computing, which needs to be connected with high bitrate transport network to support heterogeneous applications. In this case, optical network also becomes a promising option for intra and inter‐datacenter networking. In the networking field, software‐defined networking (SDN) has gained a lot of attention from both academic and industry, and it aims to provide a flexible and programmable control plane. SDN is applicable to optical network, and the optical network integrated with SDN, namely software‐defined optical network (SDON), are expected as the future transport solutions, which can provide both high bitrate connectivity and flexible network applications. The principles and applications of SDON are introduced in this chapter

Next generation control of transport networks

It is widely understood by telecom operators and industry analysts that bandwidth demand is increasing dramatically, year on year, with typical growth figures of 50% for Internet-based traffic [5]. This trend means that the consumers will have both a wide variety of devices attaching to their networks and a range of high bandwidth service requirements. The corresponding impact is the effect on the traffic engineered network (often referred to as the “transport network”) to ensure that the current rate of growth of network traffic is supported and meets predicted future demands. As traffic demands increase and newer services continuously arise, novel network elements are needed to provide more flexibility, scalability, resilience, and adaptability to today’s transport network. The transport network provides transparent traffic engineered communication of user, application, and device traffic between attached clients (software and hardware) and establishing and maintaining point-to-point or point-to-multipoint connections. The research documented in this thesis was based on three initial research questions posed while performing research at British Telecom research labs and investigating control of transport networks of future transport networks: 1. How can we meet Internet bandwidth growth yet minimise network costs? 2. Which enabling network technologies might be leveraged to control network layers and functions cooperatively, instead of separated network layer and technology control? 3. Is it possible to utilise both centralised and distributed control mechanisms for automation and traffic optimisation? This thesis aims to provide the classification, motivation, invention, and evolution of a next generation control framework for transport networks, and special consideration of delivering broadcast video traffic to UK subscribers. The document outlines pertinent telecoms technology and current art, how requirements I gathered, and research I conducted, and by which the transport control framework functional components are identified and selected, and by which method the architecture was implemented and applied to key research projects requiring next generation control capabilities, both at British Telecom and the wider research community. Finally, in the closing chapters, the thesis outlines the next steps for ongoing research and development of the transport network framework and key areas for further study