End-to-end elasticity control of cloud-network slices

The design of efficient elasticity control mechanisms for dynamic resource allocation is crucial to increase the efficiency of future cloud-network slice-defined systems. Current elasticity control mechanisms proposed for cloud- or network-slicing, only consider cloud- or network-type resources respectively. In this paper, we introduce the elaSticity in cLOud-neTwork Slices (SLOTS) which aims to extend the horizontal elasticity control to multi-providers scenarios in an end-to-end fashion, as well as to provide a novel vertical elasticity mechanism to deal with critical insufficiency of resources by harvesting underused resources on other slices. Finally, we present a preliminary assessment of the SLOTS prototype in a real testbed, revealing outcomes that suggest the viability of the proposal.Peer ReviewedPostprint (published version

Architecture and prototype of an optical UNI for the GIGA network

Orientador: Mauricio Ferreira MagalhãesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Os principais interesses do Projeto GIGA são o desenvolvimento de Tecnologias de Redes Ópticas, Serviços e Aplicações de Rede, Serviços Experimentais de Telecomunicações e Aplicações Científicas. No contexto deste Projeto, nosso grupo de pesquisa tem trabalhado no desenvolvimento de um Plano de Controle IP/WDM para integrar a Rede Cliente IP/MPLS com a Rede Óptica de Transporte WDM, de acordo com as especificações GMPLS e ASON. Especificamente neste trabalho é proposta uma Arquitetura para a UNI (User Network Interface) independente de protocolo de sinalização para prover a integralização entre as Redes Cliente e a Rede Óptica de Transporte. A Arquitetura da UNI proposta neste trabalho mantém inalterada a semântica de sinalização das redes cliente e de transporte da rede de testes do Projeto GIGA. Esta dissertação descreve como a Arquitetura desenvolvida suporta a independência quanto ao protocolo de sinalização e apresenta o protótipo implementado para validar a Arquitetura propostaAbstract: The main interests of the GIGA Project are the deployment of Optical Network Technology, Network Services and Applications, Experimental Telecommunication Services and Scientific Applications. In the context of this Project, our research group has been working on the design of an IP/WDMControl Plane to integrate the IP/MPLS Client Network with the Optical Transport Network (WDM), according to the GMPLS and ASON specifications. Specifically in this work is proposed a signaling protocol independent UNI (User Network Interface) architecture to integrate the Client and the Optical Transport Networks. The proposed UNI architecture maintains unchanged the client and transport networks signaling semantics for the GIGA testbed network. This dissertation describes how the designed architecture supports the independence of the signaling protocol and presents the prototype implemented to validate the architectureMestradoEngenharia de ComputaçãoMestre em Engenharia Elétric

iRED: A disaggregated P4-AQM fully implemented in programmable data plane hardware

Routers employ queues to temporarily hold packets when the scheduler cannot immediately process them. Congestion occurs when the arrival rate of packets exceeds the processing capacity, leading to increased queueing delay. Over time, Active Queue Management (AQM) strategies have focused on directly draining packets from queues to alleviate congestion and reduce queuing delay. On Programmable Data Plane (PDP) hardware, AQMs traditionally reside in the Egress pipeline due to the availability of queue delay information there. We argue that this approach wastes the router's resources because the dropped packet has already consumed the entire pipeline of the device. In this work, we propose ingress Random Early Detection (iRED), a more efficient approach that addresses the Egress drop problem. iRED is a disaggregated P4-AQM fully implemented in programmable data plane hardware and also supports Low Latency, Low Loss, and Scalable Throughput (L4S) framework, saving device pipeline resources by dropping packets in the Ingress block. To evaluate iRED, we conducted three experiments using a Tofino2 programmable switch: i) An in-depth analysis of state-of-the-art AQMs on PDP hardware, using 12 different network configurations varying in bandwidth, Round-Trip Time (RTT), and Maximum Transmission Unit (MTU). The results demonstrate that iRED can significantly reduce router resource consumption, with up to a 10x reduction in memory usage, 12x fewer processing cycles, and 8x less power consumption for the same traffic load; ii) A performance evaluation regarding the L4S framework. The results prove that iRED achieves fairness in bandwidth usage for different types of traffic (classic and scalable); iii) A comprehensive analysis of the QoS in a real setup of a DASH) technology. iRED demonstrated up to a 2.34x improvement in FPS and a 4.77x increase in the video player buffer fill.Comment: Preprint (TNSM under review

DESiRED -- Dynamic, Enhanced, and Smart iRED: A P4-AQM with Deep Reinforcement Learning and In-band Network Telemetry

Active Queue Management (AQM) is a mechanism employed to alleviate transient congestion in network device buffers, such as routers and switches. Traditional AQM algorithms use fixed thresholds, like target delay or queue occupancy, to compute random packet drop probabilities. A very small target delay can increase packet losses and reduce link utilization, while a large target delay may increase queueing delays while lowering drop probability. Due to dynamic network traffic characteristics, where traffic fluctuations can lead to significant queue variations, maintaining a fixed threshold AQM may not suit all applications. Consequently, we explore the question: \textit{What is the ideal threshold (target delay) for AQMs?} In this work, we introduce DESiRED (Dynamic, Enhanced, and Smart iRED), a P4-based AQM that leverages precise network feedback from In-band Network Telemetry (INT) to feed a Deep Reinforcement Learning (DRL) model. This model dynamically adjusts the target delay based on rewards that maximize application Quality of Service (QoS). We evaluate DESiRED in a realistic P4-based test environment running an MPEG-DASH service. Our findings demonstrate up to a 90x reduction in video stall and a 42x increase in high-resolution video playback quality when the target delay is adjusted dynamically by DESiRED.Comment: Preprint (Computer Networks under review

REABILITAÇÃO DE MAXILA UTILIZANDO ENXERTO AUTÓGENO INTRABUCAL - RELATO DE CASO

O planejamento protético de um rebordo alveolar edêntulo muitas vezes prevê a reconstrução óssea visando a otimização de fatores estéticos, funcionais e biomecânicos. Dentro desse raciocínio, para todo rebordo que sofre atrofia considera-se tal possibilidade. O rebordo alveolar deficiente leva freqüentemente ao posicionamento incorreto dos implantes, acarretando margem gengival imperfeita e, conseqüentemente, resultados insatisfatórios (FRANCISCHONE, 2006). Este trabalho tem o objetivo de apresentar o caso clínico da paciente que apresenta ausência dentária na arcada superior em região de incisivos, com perda óssea considerável do rebordo. Dessa forma, optou-se por reabilitação do rebordo maxilar com suficiente quantidade de osso na região de incisivos, utilizando enxerto autógeno de ramo mandibular em bloco. Concluímos que, o cirurgião deve elaborar um bom planejamento em reconstruções para a reabilitação com implantes, com o objetivo de obter informações sobre os limites de cada técnica frente à necessidade do caso, e, com isso, garantir previsibilidade e êxito das técnicas de enxertia na região bucomaxilofacial

UTILIZAÇÃO DE IMPLANTES INCLINADOS NA REABILITAÇÃO DOS MAXILARES

A insuficiência óssea em altura caracteriza maxilas com perda dos dentes posteriores. Nesses casos, uma solução imediata utilizando implantes osseointegráveis pode não ser possível, havendo necessidade de procedimentos prévios que propiciem um aumento ósseo nessas regiões. A fim de solucionar os casos mais rapidamente existe a possibilidade da inclinação dos implantes posteriores de direção distal para mesial acompanhando a anatomia do seio maxilar, possibilitando, assim, o emprego de fixações mais longas e ancorando-as em região de maior quantidade e melhor qualidade óssea (VASCONCELLOS, 2003). Este trabalho tem o objetivo de apresentar o caso clínico da paciente que apresenta ausência dentária na arcada superior, com quantia óssea considerável em região anterior e altura óssea posterior insuficiente para a instalação de implantes. Foi realizado a instalação de 6 implantes na região anterior ao seio maxilar com inclinação dos implantes posteriores no sentido postero-anterior. A técnica apresentada permitiu a reabilitação oral sem a necessidade de enxertia óssea.

Enhanced lithium depletion in Sun-like stars with orbiting planets

The surface abundance of lithium on the Sun is 140 times less than protosolar, yet the temperature at the base of the surface convective zone is not hot enough to burn Li. A large range of Li abundances in solar type stars of the same age, mass and metallicity is observed, but theoretically difficult to understand. An earlier suggestion that Li is more depleted in stars with planets was weakened by the lack of a proper comparison sample of stars without detected planets. Here we report Li abundances for an unbiased sample of solar-analogue stars with and without detected planets. We find that the planet-bearing stars have less than 1 per cent of the primordial Li abundance, while about 50 per cent of the solar analogues without detected planets have on average 10 times more Li. The presence of planets may increase the amount of mixing and deepen the convective zone to such an extent that the Li can be burned.Comment: 13 pages, 2 figure

Qual o elemento central na Rede de Atenção Psicossocial de um município de Minas Gerais?

Objetivou-se identificar, pela Análise de Rede Social, o elemento central da Rede de Atenção Psicossocial de um município de Minas Gerais e estabelecer relações de tal centralidade com o perfil dos trabalhadores. Estudo quantitativo realizado com 162 trabalhadores. Utilizou-se questionário autoaplicável e uma matriz sobre os serviços. Empreendeu-se análise descritiva e a de Rede Social para o cálculo da centralidade e confecção do mapa de redes. O hospital psiquiátrico assumiu centralidade na rede estudada. O tempo de atuação na área, escolaridade e função assistencial dos profissionais exerceram influência em relação ao conhecimento dos serviços extra-hospitalares. Concluiu-se que a centralidade do hospital psiquiátrico assinala a necessidade de ressignificação do modelo de atenção que sustenta a prática dos profissionais. Neste sentido, entende-se que o adensamento do capital social dos trabalhadores e o uso de instrumentos de gestão contribuiriam para maior articulação da Rede de Atenção Psicossocial

Enhancing Network Slicing Architectures with Machine Learning, Security, Sustainability and Experimental Networks Integration

Network Slicing (NS) is an essential technique extensively used in 5G networks computing strategies, mobile edge computing, mobile cloud computing, and verticals like the Internet of Vehicles and industrial IoT, among others. NS is foreseen as one of the leading enablers for 6G futuristic and highly demanding applications since it allows the optimization and customization of scarce and disputed resources among dynamic, demanding clients with highly distinct application requirements. Various standardization organizations, like 3GPP's proposal for new generation networks and state-of-the-art 5G/6G research projects, are proposing new NS architectures. However, new NS architectures have to deal with an extensive range of requirements that inherently result in having NS architecture proposals typically fulfilling the needs of specific sets of domains with commonalities. The Slicing Future Internet Infrastructures (SFI2) architecture proposal explores the gap resulting from the diversity of NS architectures target domains by proposing a new NS reference architecture with a defined focus on integrating experimental networks and enhancing the NS architecture with Machine Learning (ML) native optimizations, energy-efficient slicing, and slicing-tailored security functionalities. The SFI2 architectural main contribution includes the utilization of the slice-as-a-service paradigm for end-to-end orchestration of resources across multi-domains and multi-technology experimental networks. In addition, the SFI2 reference architecture instantiations will enhance the multi-domain and multi-technology integrated experimental network deployment with native ML optimization, energy-efficient aware slicing, and slicing-tailored security functionalities for the practical domain.Comment: 10 pages, 11 figure