A reduced reference video quality assessment method for provision as a service over SDN/NFV-enabled networks

139 p.The proliferation of multimedia applications and services has generarted a noteworthy upsurge in network traffic regarding video content and has created the need for trustworthy service quality assessment methods. Currently, predominent position among the technological trends in telecommunication networkds are Network Function Virtualization (NFV), Software Defined Networking (SDN) and 5G mobile networks equipped with small cells. Additionally Video Quality Assessment (VQA) methods are a very useful tool for both content providers and network operators, to understand of how users perceive quality and this study the feasibility of potential services and adapt the network available resources to satisfy the user requirements

A reduced reference video quality assessment method for provision as a service over SDN/NFV-enabled networks

139 p.The proliferation of multimedia applications and services has generarted a noteworthy upsurge in network traffic regarding video content and has created the need for trustworthy service quality assessment methods. Currently, predominent position among the technological trends in telecommunication networkds are Network Function Virtualization (NFV), Software Defined Networking (SDN) and 5G mobile networks equipped with small cells. Additionally Video Quality Assessment (VQA) methods are a very useful tool for both content providers and network operators, to understand of how users perceive quality and this study the feasibility of potential services and adapt the network available resources to satisfy the user requirements

Um arcabouço holístico para a execução de funções virtualizadas de rede : arquitetura, gerenciamento e aplicações

Orientador: Elias Procópio Duarte JúniorTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Programa de Pós-Graduação em Informática. Defesa : Curitiba, 16/12/2022Inclui referênciasÁrea de concentração: Ciência da ComputaçãoResumo: O paradigma de Virtualização de Funções de Rede (Network Function Virtualization - NFV) visa desacoplar as funções de rede de hardware dedicado, utilizando tecnologias de virtualização para implementar as funções em software. A arquitetura de referência NFV tem sido amplamente adotada, sendo esta composta por três domínios: Infraestrutura Virtualizada (Virtualized Infrastructure - VI), Gerenciamento e Orquestração de NFV (NFV Management and Orchestration - NFV-MANO), além das próprias Funções Virtualizadas de Rede (Virtualized Network Functions - VNF). Já serviços virtualizados são definidos como composições de funções virtualizadas, organizados através de topologias que estabelecem o fluxo de processamento do tráfego de rede. Apesar do grande potencial do paradigma NFV, ainda existem importantes desafios para garantir que seja amplamente adotado nas infraestruturas modernas de telecomunicação. Esta Tese tem como objetivo principal contribuir para a gerência do ciclo de vida de funções e serviços virtualizados de rede. Neste sentido assume-se a premissa de que é essencial garantir previsibilidade operacional e padronização dos elementos que atuam no domínio de VNF, i.e., das plataformas de execução de VNF e dos Sistemas de Gerenciamento de Elemento (Element Management System - EMS). São propostas na Tese arquiteturas que descrevem um modelo de execução e gerenciamento padronizado tanto para plataformas de execução de VNF, como para o EMS, compatíveis com a arquitetura de referência NFV-MANO. As arquiteturas propostas preveem protocolos, interfaces de comunicação e orientações de integração com demais elementos e sistemas NFV. Ambas as arquiteturas foram implementadas e estão disponíveis como software livre: a plataforma COVEN de execução de VNF e o EMS HoLMES. Resultados de avaliação experimental e estudos de caso são apresentados e discutidos. Também, uma investigação do impacto das arquiteturas propostas em três contextos distintos é então introduzida. Inicialmente, é explorado seu impacto como facilitador para a gerência de NFV. Em seguida, o foco fica no compartilhamento de instâncias de funções e serviços de rede, e na emulação NFV. A Tese apresenta também contribuições no contexto de serviços virtualizados de rede. Em particular, o mapeamento multidomínio consiste na implantação de serviços em infraestruturas de virtualização distribuídas. Assim, foi proposta uma estratégia de mapeamento baseado em heurísticas genéticas, denominada GeSeMa. A estratégia permite que seus operadores definam diferentes critérios de avaliação e otimização em busca de mapeamentos de serviço adequados às suas necessidades específicas. Neste sentido, o GeSeMa representa um avanço do estado da arte, pois outras soluções operam de maneira monolítica, não permitindo que operadores e gerentes de rede personalizem o esquema de otimização adotado (e.g., métricas a serem avaliadas, pesos a serem considerados e restrições de mapeamento relacionadas a cada serviço em particular). A solução foi testada em múltiplos estudos de caso e os resultados demonstram sua aplicabilidade e ?exibilidade ao lidar com diferentes cenários de otimização de mapeamentos multidomínio. Finalmente, outras duas contribuições da Tese relacionadas ao paradigma NFV são apresentadas como apêndices, nos contextos de tolerância a falhas e engenharia de tráfego.Abstract: The Network Function Virtualization (NFV) paradigm aims to decouple network functions from dedicated hardware, employing virtualization technologies to implement functions in software. The NFV reference architecture has been widely adopted. This architecture, in turn, is composed of three domains: Virtualized Infrastructure (VI), NFV Management and Orchestration (NFV-MANO), and Virtualized Network Functions (VNF). Compositions of virtualized functions define virtualized services, organized as topologies through which network trafic is steered. Despite the extraordinary potential of the NFV paradigm, there are still relevant challenges to ensure its wide adoption by modern telecommunication infrastructures. The main objective of this Thesis is to contribute to the life cycle management of virtualized network functions and services. In this context, we consider it essential to guarantee the operational predictability and organization of the elements of the VNF domain, i.e., VNF execution platforms, and the Element Management System (EMS). Thus, this Thesis presents architectures that describe a standardized execution and management model for both VNF execution platforms and EMS. The proposed architectures are compliant with the NFV-MANO reference architecture and provide protocols, communication interfaces, and guidelines for their integration with other NFV elements and systems. Both architectures have been implemented and are available as open-source software: the COVEN VNF execution platform and the HoLMES EMS. Experimental evaluation results and case studies are presented and discussed. An investigation of the impact of the proposed architectures in three di?erent contexts is also introduced. First, we explore the opportunities regarding the proposed architectures as enablers for NFV management. Then, the focus goes to sharing instances of network functions and services and NFV emulation. In addition, the Thesis presents contributions in the context of virtualized network services. Multidomain mapping consists of deploying services on distributed virtualization infrastructures. A mapping strategy based on genetic heuristics, called GeSeMa, was proposed. GeSeMa enables its operators to define multiple optimization criteria for searching candidate service mappings tailored to their specific requirements. The proposed strategy represents a state-of-the-art advance, as other solutions operate in a monolithic manner: they do not allow operators and network managers to customize the adopted evaluation setup (e.g., metrics to be evaluated, weights to be considered, and mapping constraints related to each specific service). We tested GeSeMa in multiple case studies; the results demonstrate its applicability and flexibility in dealing with different multidomain mapping optimization scenarios. Finally, two other contributions related to the NFV paradigm, approaching fault tolerance and trafic engineering, are presented as appendices

Online learning on the programmable dataplane

This thesis makes the case for managing computer networks with datadriven methods automated statistical inference and control based on measurement data and runtime observations—and argues for their tight integration with programmable dataplane hardware to make management decisions faster and from more precise data. Optimisation, defence, and measurement of networked infrastructure are each challenging tasks in their own right, which are currently dominated by the use of hand-crafted heuristic methods. These become harder to reason about and deploy as networks scale in rates and number of forwarding elements, but their design requires expert knowledge and care around unexpected protocol interactions. This makes tailored, per-deployment or -workload solutions infeasible to develop. Recent advances in machine learning offer capable function approximation and closed-loop control which suit many of these tasks. New, programmable dataplane hardware enables more agility in the network— runtime reprogrammability, precise traffic measurement, and low latency on-path processing. The synthesis of these two developments allows complex decisions to be made on previously unusable state, and made quicker by offloading inference to the network. To justify this argument, I advance the state of the art in data-driven defence of networks, novel dataplane-friendly online reinforcement learning algorithms, and in-network data reduction to allow classification of switchscale data. Each requires co-design aware of the network, and of the failure modes of systems and carried traffic. To make online learning possible in the dataplane, I use fixed-point arithmetic and modify classical (non-neural) approaches to take advantage of the SmartNIC compute model and make use of rich device local state. I show that data-driven solutions still require great care to correctly design, but with the right domain expertise they can improve on pathological cases in DDoS defence, such as protecting legitimate UDP traffic. In-network aggregation to histograms is shown to enable accurate classification from fine temporal effects, and allows hosts to scale such classification to far larger flow counts and traffic volume. Moving reinforcement learning to the dataplane is shown to offer substantial benefits to stateaction latency and online learning throughput versus host machines; allowing policies to react faster to fine-grained network events. The dataplane environment is key in making reactive online learning feasible—to port further algorithms and learnt functions, I collate and analyse the strengths of current and future hardware designs, as well as individual algorithms

Bowdoin Orient v.131, no.1-24 (1999-2000)

https://digitalcommons.bowdoin.edu/bowdoinorient-2000s/1000/thumbnail.jp