Multi-Layer Architektur und System Design von Internet Protocol (IP) und Optischen Netzwerken

The modeling of multi-layer networks is well-researched problem, but existing models for IP-optical integration do not consider technology specific capabilities and operational aspects for employing dynamic optical circuits in IP networks. This thesis presents an ILP-based model which identifies and incorporates novel constraints for numerous technology specific aspects, such as IP forwarding capabilities and behavior of routing protocols. Novel solutions for critical operational aspects of IP-optical integration, such as optical circuit decommissioning and computation under unknown traffic conditions, are also proposed in this thesis. The thesis identifies changes in routing as a major deterrent for employing dynamic optical circuits in IP networks, and proposes the new Optical Bypass approach to address the same. Quantitative studies presented indicate that the introduction of an optical circuit under this approach significantly reduces the effect on IP routing, while lowering optical capacity requirements as compared to the traditional SPF based approaches. The proposed solution can also compute near-optimal solutions under unknown IP traffic matrix conditions, making it ideal for application in dynamic network scenarios. The thesis also addresses specific management challenges with IP-optical integration, and outlines solutions to address the same. The solutions are built around enabling coordination of management subsystems in the two network layers. The thesis presents the general architecture to facilitate coordination between management subsystems in a programmable fashion and demonstrates the capability of the architecture to be used in legacy as well as SDN-capable infrastructure. The thesis also outlines the design and implementation of the first open-source PCE, which is a critical management subsystem for enabling multi-layer path computation in IP-optical networks.Grundsätzlich ist die Modellierung von Multilayer-Netzen ein bekanntes Problem, dennoch lassen die vorhandenen Modelle für IP-optische Integration viele technologiespezifische Eigenschaften und kritische Aspekte bei Einrichtung und Betrieb dynamischer optischer Verbindungen in IP-Netzwerken außer Acht. Hierzu gehören vor allem die Eigenheiten des Forwarding, sowie das Verhalten von Routingprotokollen. Die vorliegende Dissertation präsentiert ein ILP Modell, dass solche Aspekte und Bedingungen identifiziert und integriert, sowie die Notwendigkeit hierfür anhand numerischer Evaluierung nachweist. Die Modellierungsaspekte der IP-optischen Integration umfassen bezüglich des Netzbetriebs vor allem Probleme wie die optimale Berechnung im Falle einer unbekannten Verkehrsmatrix sowie deren Verbindungsabbau. Ein wesentliches Hindernis in dynamische IP-optischen Netzwerken sind die aus ihrer Einrichtung resultierenden protokollspezifischen Änderungen im Routing. Als Lösung wird der optische Bypass vorgeschlagen. Die Untersuchungen zeigen, dass der Einsatz optischer Bypässe die Auswirkungen auf das IP-Routing stark reduziert und gleichzeitig die dafür notwendigen Kapazitätsanforderungen verringert. Damit sind optische Bypässe ebenfalls für Anwendungsszenarien geeignet, in denen die IP-Verkehrsmatrix nicht bekannt ist. Im Weiteren werden noch Probleme aus dem Bereich Netzwerkmanagement behandelt, die sich spezifisch aus der IP-optischen Integration entwickeln, und es werden entsprechende Lösungsansätze vorgestellt. Diese basieren auf der Abstimmung und dem koordinierten Betrieb der Management-Subsysteme in den beiden betroffenen Netzschichten. Gezeigt wird dann eine allgemeine Architektur, die eine Koordination von Management-Subsystemen (auch für SDN), in programmierbarer Form ermöglicht. Außerdem wird der Entwurf und die Implementierung des Open Source PCE beschrieben, welches die Berechnung von Multilayer Verbindungswegen in IP-optischen Netzwerken ermöglicht

Automatic Intent-Based Secure Service Creation Through a Multilayer SDN Network Orchestration

Growing traffic demands and increasing security awareness are driving the need for secure services. Current solutions require manual configuration and deployment based on the customer's requirements. In this work, we present an architecture for an automatic intent-based provisioning of a secure service in a multilayer - IP, Ethernet, and optical - network while choosing the appropriate encryption layer using an open-source software-defined networking (SDN) orchestrator. The approach is experimentally evaluated in a testbed with commercial equipment. Results indicate that the processing impact of secure channel creation on a controller is negligible. As the time for setting up services over WDM varies between technologies, it needs to be taken into account in the decision-making process.Comment: Parts of the presented work has received funding from the European Commission within the H2020 Research and Innovation Programme, under grant agreeement n.645127, project ACIN

Intent-Based In-flight Service Encryption in Multi-Layer Transport Networks

We demonstrate multi-layer encrypted service provisioning via the ACINO orchestrator. ACINO combines a novel intent interface with an ONOS-based SDN orchestrator to facilitate encrypted services at IP, Ethernet and optical network layers.Comment: Optical Fiber Communication Conferenc

ACINO: Second year report on dissemination and communication activities

This ACINO deliverable presents the communication and dissemination activities performed by the consortium during the first two years of the project. We have communicated using our website, Twitter account and by various communication actions: The website saw over 3000 unique visitors during the first year and over 4000 during the second year; The consortium Twitter account had 49 followers at the end of the first year and 80 at the end of the second year. We posted 50 tweets during the first year and 40 more during the second year; We also held a press release and an interview in a magazine during the first year, and had three more similar communication actions during the second year. The dissemination activities have been composed of participation in public events where the goals and concepts of ACINO were presented via publications, presentation, workshops, courses and demonstrations. Overall, over forty different dissemination activities have been performed: An article has been published in peer-reviewed, open access Journal of Green Engineering; Eighteen articles have been published in conferences: four during the first year and fourteen during the second. One of them was a post-deadline and six were invited papers; We have co-organised three workshops: the Workshop on Network Function Virtualization and Programmable Networks at EUCNC 2015, the first Workshop on Multi-Layer Network Orchestration (NetOrch) at ICTON 2016 and the stand-alone ONOS/CORD workshop; We have held 16 talks, tutorial, courses and demonstrations; Consortium members have won two prizes for work related to ACINO: a team of developers won the 3rd prize of the ONOS Build Hackathon, and Telefónica won the Best SDN-NFV solution award at the LTE and 5G World conference by presenting a solution in which Sedona Systems was involved; We have contributed to six IETF standardisation documents and done some implementation and test of these standards. We have contributed to two open source projects: the NetPhony and ONOS controllers, with the implementation of main features being accepted and merged to the core code of these open source projects. Finally, the project has devised detailed plans for its dissemination activities for the last year of the project. We have: Confirmed plans for the organisation of a workshop, the second edition of the NetOrch workshop, co-located with the ICTON conference; A solid plan for continued dissemination in conferences (already five accepted conference papers, five talk invitations and a list of conferences of interest) and in peer-reviewed journals, with one article accepted for publication in the Journal of Lightwave Technology, two articles under review and plans for four more; Some more planned contribution to open source projects

Artificial intelligence (AI) methods in optical networks: A comprehensive survey

Producción CientíficaArtificial intelligence (AI) is an extensive scientific discipline which enables computer systems to solve problems by emulating complex biological processes such as learning, reasoning and self-correction. This paper presents a comprehensive review of the application of AI techniques for improving performance of optical communication systems and networks. The use of AI-based techniques is first studied in applications related to optical transmission, ranging from the characterization and operation of network components to performance monitoring, mitigation of nonlinearities, and quality of transmission estimation. Then, applications related to optical network control and management are also reviewed, including topics like optical network planning and operation in both transport and access networks. Finally, the paper also presents a summary of opportunities and challenges in optical networking where AI is expected to play a key role in the near future.Ministerio de Economía, Industria y Competitividad (Project EC2014-53071-C3-2-P, TEC2015-71932-REDT

Coordinated Computation of Multi-layer Paths via Inter-layer PCE Communication: Standards, Interoperability and Deployment

The Path Computation Element (PCE) is positioned nowadays as one of the solutions that almost every carrier will eventually deploy. The PCE architecture as well as a number of components, including the PCE Communication Protocol (PCEP), have been standardized by the IETF. However, a number of challenges remain to be solved on its way from standards to deployment. In particular, the existing proposals for multilayer path computation within the PCE framework need to be further developed and tested, before considering their possible integration into operational networks. This is especially true for the interoperability of the various PCE implementations and the extensions such as the Virtual Network Topology Manager (VNTM) which cannot be taken for granted. This paper presents a functional implementation of coordinated computation of multilayer paths supported through inter-layer PCE communication, where one PCE is developed by industry and the other as an open-source effort. To this end, we consider an IP/MPLS network deployed over a Wavelength Switched Optical Network (WSON), each of which deploying its own PCE, in an attempt to create an inter-operable multilayer solution. We discuss the key challenges that the research community will face in this area, which in turn will drive a considerable part of the upcoming efforts in terms of standardizationPostprint (published version

Multi-layer resilience schemes and their control plane support

Network operators design and manage IP/MPLS and optical networks on a per-layer basis, to the point that they are run as different business areas within the operator. However, there are clear CAPEX and OPEX savings that network operators can achieve by simplifying the network infrastructure. Moreover, the evolution of optical equipment and the introduction of network programmability are accelerating the adoption of multi-layer schemes in real networks. This paper revisions the planning process considering resilience schemes for IP and optical networks. It also presents an evolutionary view on the control plane and SDN paradigms that enable the support of multi-layer schemes in real networks