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Network programming as a service : an innovation friendly business model; Programabilidade de redes como serviço : um modelo de negócios propício à inovação

Jesus, Wanderson Paim de
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.66%
Computer networks have evolved to accommodate a wide variety of services, such as streaming of high quality videos and delay-sensitive content delivery. These services have increased the demand for features not originally considered in the Internet. Aiming to address novel network demands quickly, some researchers proposed Programmable Networks, in which network devices behavior can be changed using applications. Notwithstanding, such behavior might not be a consensus between computer network stakeholders. The emergence of Virtualized Networks overcame this issue by allowing the coexistence of multiple virtual networks on the same physical infrastructure. Finally, the convergence of programmability and virtualization techniques are explored within a third concept, the Programmable Virtual Networks (PVN). Faced with this new reality, network administrators are no longer just looking at network devices. They are looking at a system made of virtual devices and applications that define each virtual network behavior. This requires not just new tools and management approaches, over and above that, requires new thinking. PVN deployments are found mostly in shared experimental facilities (also known as testbeds) and Cloud Computing environments. Testbeds are very innovation friendly...

A case for spiking neural network simulation based on configurable multiple-FPGA systems

Yang, Shufan; Wu, Qiang; Li, Renfa
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.32%
Recent neuropsychological research has begun to reveal that neurons encode information in the timing of spikes. Spiking neural network simulations are a flexible and powerful method for investigating the behaviour of neuronal systems. Simulation of the spiking neural networks in software is unable to rapidly generate output spikes in large-scale of neural network. An alternative approach, hardware implementation of such system, provides the possibility to generate independent spikes precisely and simultaneously output spike waves in real time, under the premise that spiking neural network can take full advantage of hardware inherent parallelism. We introduce a configurable FPGA-oriented hardware platform for spiking neural network simulation in this work. We aim to use this platform to combine the speed of dedicated hardware with the programmability of software so that it might allow neuroscientists to put together sophisticated computation experiments of their own model. A feed-forward hierarchy network is developed as a case study to describe the operation of biological neural systems (such as orientation selectivity of visual cortex) and computational models of such systems. This model demonstrates how a feed-forward neural network constructs the circuitry required for orientation selectivity and provides platform for reaching a deeper understanding of the primate visual system. In the future...

Application-aware software-defined networking to accelerate mapreduce applications

Neves, Marcelo Veiga
Fonte: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre Publicador: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
16.36%
O modelo de programação MapReduce (MR), tal como implementado por Hadoop, tornou-se o padrão de facto para análise de dados de larga escala em data centers, sendo também a base para uma grande variedade de tecnologias de Big Data que são utilizadas atualmente. Neste contexto, Hadoop é um framework escalável que permite a utilização de um grande número de servidores para manipular os crescentes conjutos de dados da área de Big Data. Enquanto capacidade de processamento e E/S podem ser escalados através da adição de mais servidores, isto gera um tráfego acentuado na rede. No caso de MR, a fase que realiza comunicações via rede representa uma significante parcela do tempo total de execução. Esse problema é agravado ainda mais quando os padrões de comunicação são desbalanceados, o que não é incomum para muitas aplicações MR.MR normalmente executa em grandes data centers (DC) de commodity hardware. A rede de tais DCs normalmente utiliza topologias densas que oferecem múltiplos caminhos alternativos (multipath) entre cada par de hosts. Este tipo de topologia, combinado com a emergente tecnologia de redes definidas por software (SDN), possibilita a criação de protocolos inteligentes para distribuir o tráfego entre os diferentes caminhos disponíveis e reduzir o tempo de execução das aplicações. Assim...

Projeto de Sistemas Integrados de Propósito Geral Baseados em Redes em Chip Expandindo as Funcionalidades dos Roteadores para Execução de Operações: A plataforma IPNoSys

Araújo, Sílvio Roberto Fernandes de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Sistemas e Computação; Ciência da Computação Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Sistemas e Computação; Ciência da Computação
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
26.27%
It bet on the next generation of computers as architecture with multiple processors and/or multicore processors. In this sense there are challenges related to features interconnection, operating frequency, the area on chip, power dissipation, performance and programmability. The mechanism of interconnection and communication it was considered ideal for this type of architecture are the networks-on-chip, due its scalability, reusability and intrinsic parallelism. The networks-on-chip communication is accomplished by transmitting packets that carry data and instructions that represent requests and responses between the processing elements interconnected by the network. The transmission of packets is accomplished as in a pipeline between the routers in the network, from source to destination of the communication, even allowing simultaneous communications between pairs of different sources and destinations. From this fact, it is proposed to transform the entire infrastructure communication of network-on-chip, using the routing mechanisms, arbitration and storage, in a parallel processing system for high performance. In this proposal, the packages are formed by instructions and data that represent the applications, which are executed on routers as well as they are transmitted...

Region-based techniques for modeling and enhancing cluster OpenMP performance

Cai, Jie
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
Português
Relevância na Pesquisa
16.23%
Cluster OpenMP enables the use of the OpenMP shared memory programming clusters. Intel has released a cluster OpenMP implementation called Intel Cluster OpenMP (CLOMP). While this offers better programmability than message passing alternatives such as the Message Passing Interface (MPI), such convenience comes with overheads resulting from having to maintain the consistency of underlying shared memory abstractions. CLOMP is no exception. This thesis introduces models for understanding these overheads of cluster OpenMP implementations like CLOMP and proposes techniques for enhancing their performance. Cluster OpenMP systems are usually implemented using page-based software distributed shared memory systems. A key issue for such system is maintaining the consistency of the shared memory space. This forms a major source of overhead, and it is driven by detecting and servicing page faults. To understand these systems, we evaluate their performance with different OpenMP applications, and we also develop a benchmark, called MCBENCH, to characterize the memory consistency costs. Using MCBENCH, we discover that this overhead is proportional to the number of writers to the same shared page and the number of shared pages. Furthermore...

Improving Networking Server Performance with Programmable Network Interfaces

Kim, Hyong-youb; Kim, Hyong-youb
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
36.66%
Masters Thesis; Networking servers, such as web servers, have been widely deployed in recent years. While developments in the operating system and applications continue to improve server performance, programmable network interfaces with local memory provide new opportunities to improve server performance through extended network services on the network interface. However, due to their embedded nature, programmable processors on the network interface may suffer from inadequate processing power when compared to non-programmable application-specific network interfaces. This thesis first shows that exploiting a multiprocessor architecture and task-level concurrency in network interface processing enables programmable network interfaces to overcome the performance disadvantages over application-specific network interfaces that result from programmability. Then, the thesis presents a network service on a programmable network interface that exploits the storage capacity of the interfaces to alleviate the local I/O interconnect bottleneck, thereby improving server performance. Thus, these two results show that programmable network interfaces can offset the performance disadvantages due to programmability and improve networking server performance through extended network services that exploit their computation power and storage capacity.

Improving networking server performance with programmable network interfaces

Kim, Hyong-Youb
Fonte: Universidade Rice Publicador: Universidade Rice
Português
Relevância na Pesquisa
26.65%
Networking servers, such as web servers, have been widely deployed in recent years. While developments in the operating system and applications continue to improve server performance, programmable network interfaces with local memory provide new opportunities to improve server performance through extended network services on the network interface. However, due to their embedded nature, programmable processors on the network interface may suffer from inadequate processing power when compared to non-programmable application-specific network interfaces. This thesis first shows that exploiting a multiprocessor architecture and task-level concurrency in network interface processing enables programmable network interfaces to overcome the performance disadvantages over application-specific network interfaces that result from programmability. Then, the thesis presents a network service on a programmable network interface that exploits the storage capacity of the interfaces to alleviate the local I/O interconnect bottleneck, thereby improving server performance. Thus, these two results show that programmable network interfaces can offset the performance disadvantages due to programmability and improve networking server performance through extended network services that exploit their computation power and storage capacity.

WARP, a UnifiedWireless Network Testbed for Education and Research

Amiri, Kiarash; Sun, Yang; Murphy, Patrick; Hunter, Chris; Cavallaro, Joseph R.; Sabharwal, Ashutosh
Fonte: IEEE Publicador: IEEE
Tipo: Conference paper
Português
Relevância na Pesquisa
36.46%
In this paper, we introduce the Wireless Open-Access Research Platform (WARP) developed at CMC lab, Rice University. WARP provides a scalable and configurable platform mainly designed to prototype wireless communication algorithms for educational and research oriented applications. Its programmability and flexibility makes it easy to implement various physical and network layer protocols and standards. Moreover, the online open-access WARP repository is used to document and share different wireless architectures and cross-layer designs developed at educational and research centers. This repository is a fast and easy solution for students and researchers with a wide range of backgrounds in hardware implementation and algorithm development to collaborate and initiate multi-disciplinary system designs.

WARP, a Modular Testbed for Configurable Wireless Network Research at Rice

Amiri, Kiarash; Sun, Yang; Murphy, Patrick; Hunter, Chris; Cavallaro, Joseph R.; Sabharwal, Ashutosh
Fonte: IEEE Publicador: IEEE
Tipo: Conference paper
Português
Relevância na Pesquisa
26.27%
Wireless Open-Access Research Platform (WARP), developed at CMC lab, Rice University, provides a scalable and configurable platform for wireless network research. Its programmability and flexibility makes it easy to prototype and implement various physical and network layer protocols and standards. In order to share algorithms and implementations developed at different research centers, an online open-access repository is used so that wireless network researchers can collaborate to initiate multi-disciplinary system designs.

Proposta e validação de nova arquitetura de roteamento IP com separação de planos; Proposal and evaluation of a new IP routing architecture with separation of planes

Marcelo Ribeiro Nascimento
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 21/06/2012 Português
Relevância na Pesquisa
26.17%
Os roteadores atuais implementam uma arquitetura verticalmente integrada composta de uma camada de software e um hardware proprietários. Este modelo resulta em soluções de alto custo e inviabiliza a experimentação de novas idéias. Em contrapartida, existem alternativas de alta flexibilidade baseadas em software e, consequentemente, de baixo custo. Entretanto, essas soluções apresentam baixo desempenho. Motivado pela disponibilidade de uma API aberta para programação do plano de encaminhamento (ex. OpenFlow), esta dissertação apresenta uma proposta de arquitetura de roteamento IP com separação de planos. Trata-se de uma abordagem que procura combinar o alto desempenho de hardwares de prateleira (commodities) com a flexibilidade de uma pilha de roteamento executada remotamente em computadores de uso geral. O grande desafio é garantir confiabilidade, escalabilidade e desempenho à rede, a partir de um controle remoto e centralizado sobre uma arquitetura que permita maior flexibilidade no mapeamento entre os elementos de controle e encaminhamento. O resultado corresponde a uma nova proposta de roteamento IP com perspectivas promissoras do ponto de vista do custo e da flexibilidade. Com o objetivo de avaliar a arquitetura proposta foi desenvolvido um protótipo com base em uma versão simplificada do modelo. Os resultados da avaliação apresentados nesta dissertação comprovam a viabilidade da arquitetura.; Today's networking gear follows the model of computer mainframes...

Towards secure software-defined networks

Magalhães, Cátia Alexandra Bimbo
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2015 Português
Relevância na Pesquisa
16.31%
Tese de mestrado, Informática, Universidade de Lisboa, Faculdade de Ciências, 2015; Computer networks are complex, difficult to configure and manage. The number of devices and their diversity hampers the process of configuration and management. Besides these aspects, there are also other requirements to be fulfilled, e.g. introduction of security policies or intrusion detection. Issues related with security are particularly important. But makes network management harder. Software-Defined Networking (SDN) was to take the complexity and cost of managing network infrastructures. SDN offers flexibility, interoperability between devices and introduces programmability in the network. Besides addressing the limitations of existing network infrastructures, it allows their development and innovation. Security is still one of the major challenges of SDN. Given that security issues are a priority concern for the adoption of SDN, it is necessary to ensure the essential security mechanisms for the proper functioning of the infrastructure. In this sense, control plane communications represent the most crucial link between network devices and, at the same time, one of the weakest links from a security and dependability viewpoint. By compromising or controlling the control plane communications an attacker can easily take over the entire network. With this issue in mind...

Traffic Management Applications for Stateful SDN Data Plane

Cascone, Carmelo; Pollini, Luca; Sanvito, Davide; Capone, Antonio
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.06%
The successful OpenFlow approach to Software Defined Networking (SDN) allows network programmability through a central controller able to orchestrate a set of dumb switches. However, the simple match/action abstraction of OpenFlow switches constrains the evolution of the forwarding rules to be fully managed by the controller. This can be particularly limiting for a number of applications that are affected by the delay of the slow control path, like traffic management applications. Some recent proposals are pushing toward an evolution of the OpenFlow abstraction to enable the evolution of forwarding policies directly in the data plane based on state machines and local events. In this paper, we present two traffic management applications that exploit a stateful data plane and their prototype implementation based on OpenState, an OpenFlow evolution that we recently proposed.; Comment: 6 pages, 9 figures

Service Provider DevOps network capabilities and tools

Steinert, Rebecca; John, Wolfgang; Sköldström, Pontus; Pechenot, Bertrand; Gulyás, András; Pelle, István; Lévai, Tamás; Németh, Felicián; Kim, Juhoon; Meirosu, Catalin; Cai, Xuejun; Fu, Chunyan; Pentikousis, Kostas; Sharma, Sachin; Papafili, Ioan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.23%
This report provides an understanding of how the UNIFY Service Provider (SP)-DevOps concept can be applied and integrated with a combined cloud and transport network NFV architecture. Specifically, the report contains technical descriptions of a set of novel SP-DevOps tools and support functions that facilitate observability, troubleshooting, verification, and VNF development processes. The tools and support functions are described in detail together with their architectural mapping, giving a wider understanding of the SP-DevOps concept as a whole, and how SP-DevOps tools can be used for supporting orchestration and programmability in the UNIFY NFV framework. The concept is further exemplified in a case study for deployment and scaling of an Elastic Firewall.; Comment: This is the public deliverable D4.2 of the EU FP7 UNIFY project (ICT-619609) - "Proposal for SP-DevOps network capabilities and tools". Original Deliverable published at https://www.fp7-unify.eu/files/fp7-unify-eu-docs/UNIFY-WP4-D4.2%20Proposal%20for%20SP-DevOps%20network%20capabilities%20and%20tools.pdf

Programming Flows in Dense Mobile Environments: A Multi-user Diversity Perspective

Gasparis, Ioannis; Kozat, Ulas C.; Sunay, M. Oguz
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/06/2015 Português
Relevância na Pesquisa
26.71%
The emergence of OpenFlow and Software Defined Networks brings new perspectives into how we design the next generation networks, where the number of base stations/access points as well as the devices per subscriber will be dramatically higher. In such dense environments, devices can communicate with each other directly and can attach to multiple base stations (or access points) for simultaneous data communication over multiple paths. This paper explores how networks can maximally enable this multi-path diversity through network programmability. In particular, we propose programmable flow clustering and set policies for inter-group as well as intra-group wireless scheduling. Further, we propose programmable demultiplexing of a single network flow onto multiple paths before the congestion areas and multiplexing them together post congestion areas. We show the benefits of such programmability first for legacy applications that cannot take advantage of multi-homing without such programmability. We then evaluate the benefits for smart applications that take advantage of multi-homing by either opening multiple TCP connections over multiple paths or utilizing a transport protocol such as MP-TCP designed for supporting such environments. More specifically...

Disaster-Resilient Control Plane Design and Mapping in Software-Defined Networks

Savas, S. Sedef; Tornatore, Massimo; Habib, M. Farhan; Chowdhury, Pulak; Mukherjee, Biswanath
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/09/2015 Português
Relevância na Pesquisa
26.31%
Communication networks, such as core optical networks, heavily depend on their physical infrastructure, and hence they are vulnerable to man-made disasters, such as Electromagnetic Pulse (EMP) or Weapons of Mass Destruction (WMD) attacks, as well as to natural disasters. Large-scale disasters may cause huge data loss and connectivity disruption in these networks. As our dependence on network services increases, the need for novel survivability methods to mitigate the effects of disasters on communication networks becomes a major concern. Software-Defined Networking (SDN), by centralizing control logic and separating it from physical equipment, facilitates network programmability and opens up new ways to design disaster-resilient networks. On the other hand, to fully exploit the potential of SDN, along with data-plane survivability, we also need to design the control plane to be resilient enough to survive network failures caused by disasters. Several distributed SDN controller architectures have been proposed to mitigate the risks of overload and failure, but they are optimized for limited faults without addressing the extent of large-scale disaster failures. For disaster resiliency of the control plane, we propose to design it as a virtual network...

Construction of a Scalable, Uniform and Universal Quantum Network and Its Applications

Wang, An Min
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.29%
We present a possible candidate of construction of a scalable, uniform and universal quantum network, which is built from quantum gates to elements of quantum circuit, again to quantum subnetworks and finally to an entire quantum network. Our scheme can overcome some difficulties of the existing schemes and makes improvements to different extent in the scale of quantum network, ability of computation, implementation of engineering, efficiency of quantum network, universality, compatibility, design principle, programmability, fault tolerance, error control, industrialization and commercialization {\it et. al} aspects. As the applications of this construction scheme, we obtain the entire quantum networks for Shor's algorithm, Grover's algorithm and solving Schr\"odinger equation in general. This implies that the scalable, uniform and universal quantum networks are able to generally describe the known main results and can be further applied to more interesting examples in quantum computations.; Comment: 38 pages, Revised Version, Revtex

Network Issues in Virtual Machine Migration

Ibn-Khedher, Hatem; Abd-Elrahman, Emad; Afifi, Hossam; Forestier, Jacky
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/08/2015 Português
Relevância na Pesquisa
26.27%
Software Defined Networking (SDN) is based basically on three features: centralization of the control plane, programmability of network functions and traffic engineering. The network function migration poses interesting problems that we try to expose and solve in this paper. Content Distribution Network virtualization is presented as use case.; Comment: 6 pages, 8 figures

Cross-Layer Software-Defined 5G Network

Yang, Mao; Li, Yong; Hu, Long; Li, Bo; Jin, Depeng; Chen, Sheng; Yan, Zhongjiang
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/11/2014 Português
Relevância na Pesquisa
26.32%
In the past few decades, the world has witnessed a rapid growth in mobile communication and reaped great benefits from it. Even though the fourth generation (4G) mobile communication system is just being deployed worldwide, proliferating mobile demands call for newer wireless communication technologies with even better performance. Consequently, the fifth generation (5G) system is already emerging in the research field. However, simply evolving the current mobile networks can hardly meet such great expectations, because over the years the infrastructures have generally become ossified, closed, and vertically constructed. Aiming to establish a new paradigm for 5G mobile networks, in this article, we propose a cross-layer software-defined 5G network architecture. By jointly considering both the network layer and the physical layer together, we establish the two software-defined programmable components, the control plane and the cloud computing pool, which enable an effective control of the mobile network from the global perspective and benefit technological innovations. Specifically, by the cross-layer design for software-defining, the logically centralized and programmable control plane abstracts the control functions from the network layer down to the physical layer...

Reconfigurable Network Systems and Software-Defined Networking

Zilberman, Noa; Rotsos, Charalampos; Moore, Andrew W.
Fonte: IEEE Publicador: IEEE
Tipo: Article; published version
Português
Relevância na Pesquisa
26.61%
This is the final version of the article. It first appeared from IEEE via http://dx.doi.org/10.1109/JPROC.2015.2435732; Modern high-speed networks have evolved from relatively static networks to highly adaptive networks facilitating dynamic reconfiguration. This evolution has influenced all levels of network design and management, introducing increased programmability and configuration flexibility. This influence has extended from the lowest level of physical hardware interfaces to the highest level of network management by software. A key representative of this evolution is the emergence of softwaredefined networking (SDN). In this paper, we review the current state of the art in reconfigurable network systems, covering hardware reconfiguration, SDN, and the interplay between them. We take a top-down approach, starting with a tutorial on software-defined networks. We then continue to discuss programming languages as the linking element between different levels of software and hardware in the network. We review electronic switching systems, highlighting programmability and reconfiguration aspects, and describe the trends in reconfigurable network elements. Finally, we describe the state of the art in the integration of photonic transceiver and switching elements with electronic technologies...

Algoritmo de agrupamento Fuzzy C-Means para aprendizado e tomada de decisão em redes ópticas de próxima geração  ; Fuzzy C-Means algorithm for learning and decision making in next generation optical network

Tronco, Tania Regina
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 31/08/2015 Português
Relevância na Pesquisa
26.36%
As redes ópticas têm evoluído de forma contínua dentro de um paradigma de aumento das taxas de transmissão e extensão dos enlaces, devido à demanda crescente de banda em função do crescimento do tráfego da Internet. Além disso, atualmente, diversas propostas vêm sendo implementadas visando torná-las mais dinâmicas e flexíveis. Uma destas propostas que atualmente está no âmbito de pesquisa e desenvolvimento refere-se às redes ópticas definidas por software (Software Defined Optical Network, SDON). Nas SDONs, o plano de controle é desacoplado do plano de encaminhamento de dados possibilitando que controladores remotos configurem em tempo real diversos parâmetros dos canais ópticos, tais como a taxa de transmissão, o formato de modulação, a largura do espectro, entre outros. Nestas redes, o sistema de controle torna-se bastante complexo, uma vez que diversos parâmetros têm que ser ajustados de forma dinâmica e autônoma, ou seja, com a mínima intervenção humana. O emprego de técnicas de inteligência computacional em tal controle possibilita a configuração autônoma dos parâmetros dos equipamentos com base em dados coletados por monitores de rede e o aprendizado, a partir de eventos passados, visando a otimização do desempenho da rede. Esta arquitetura de controle constitui um novo paradigma na evolução das redes ópticas...