Game-based communication in Network Control Systems

Network based Control Systems (NCSs) are more and more often selected in designing distributed control systems due to both economic and practical reasons. Today designs of NCSs frequently involve the non-expensive wireless communication instead of traditional wired links. Such systems are usually calledWireless Sensor Networks (WSNs) and are used for many other purposes as well. While convenient in installation and management, wireless links are susceptible to noise and not very reliable. While common approach of data delivery relies on routing (proactive or reactive), this paper presents a different approach to designing wireless NCSs. In the proposed approach every node takes an independent decision as a result of a game between the nodes. Unlike the routing solutions, the nodes never create any path, and even have no knowledge concerning network topology

QoS Routing of VoIP using a Modified Widest-Shortest Routing Algorithm

Implementation of current real time services (of which one of the more important is Voice over IP) on the current Internet face many obstacles, among them the issue of routing. Quality of service (QoS) routing, attempts to provide real time services with the required guarantees to achieve acceptable performance. In this paper we study VoIP routing using the Quality of Service (QSR) network simulator utilizing the Widest-Shortest routing algorithm to provide QoS using different metrics. We show that this algorithm using a modified cost metric based on the hop-normalized is able to route real time traffic away from congested links thus providing acceptable jitter, end-to-end delay and throughput to satisfy real time services requirements

Low-Latency Routing on Mesh-Like Backbones

Early in in the Internet's history, routing within a single provider's WAN centered on placing traffic on the shortest path. More recent traffic engineering efforts aim to reduce congestion and/or increase utilization within the status quo of greedy shortest-path first routing on a sparse topology. In this paper, we argue that this status quo of routing and topology is fundamentally at odds with placing traffic so as to minimize latency for users while avoiding congestion. We advocate instead provider backbone topologies that are more mesh-like, and hence better at providing multiple low-latency paths, and a routing system that directly considers latency minimization and congestion avoidance while dynamically placing traffic on multiple unequal-cost paths. We offer a research agenda for achieving this new low-latency approach to WAN topology design and routing

Routage distribué et adaptatif fondé sur la théorie des jeux

International audienceDans cet article, nous présentons un algorithme de routage distribué multi-flots permettant de choisir des chemins debout en bout dans un réseau. Celui-ci converge vers une configuration dans laquelle aucun flot ne peut améliorer sondélai de bout en bout en changeant de chemin (équilibre de Nash).Notre algorithme est robuste aux erreurs de mesures, tolère les mesures obsolètes, et ne nécessite pas de synchronisationd’horloge. Notre preuve de concept est implémentée sous forme d’un contrôleur OpenFlow, et nous l’évaluons sur uneplate-forme d’émulation utilisant Mininet

On Cross-Layer Routing in Wireless Multi-Hop Networks

International audienc

АДАПТИВНАЯ МНОГОПУТЕВАЯ МАРШРУТИЗАЦИЯ

 Предложен алгоритм адаптивной многопутевой маршрутизации (АМР) для динамического конструирования трафика в пределах автономной системы. Он отличается от известного алгоритма оптимизированной многопутевой маршрутизации отсутствием необходимости хранить и обновлять информацию о всей сети в каждом ее узле. Алгоритм АМР основан на механизме сообщений об обратном давлении, который позволяет осуществлять распределение нагрузки на локальном уровне, а также прогнозировать размеры служебного трафик

Multi-path BGP: motivations and solutions

Although there are many reasons towards the adoption of a multi-path routing paradigm in the Internet, nowadays the required multi-path support is far from universal. It is mostly limited to some domains that rely on IGP features to improve load distribution in their internal infrastructure or some multi-homed parties that base their load balance on traffic engineering. This chapter explains the motivations for a multi-path routing Internet scheme, commenting the existing alternatives and detailing two new proposals. Part of this work has been done within the framework of the Trilogy research and development project, whose main objectives are also commented in the chapter.Part of this work has been done within the framework of the Trilogy research and development project. The different research partners of this project are: British Telecom, Deutsche Telekom, NEC Europe, Nokia, Roke Manor Research Limited, Athens University of Economics and Business, University Carlos III of Madrid, University College London, Universit Catholique de Louvain and Stanford University.European Community's Seventh Framework ProgramEn prens

Contention-based Nonminimal Adaptive Routing in High-radix Networks

Adaptive routing is an efficient congestion avoidance mechanism for modern Datacenter and HPC networks. Congestion detection traditionally relies on the occupancy of the router queues. However, this approach can hinder performance due to coarse-grain measurements with small buffers, and potential routing oscillations with large buffers. We introduce an alternative mechanism, labelled Contention-Based Adaptive Routing. Our mechanism adapts routing based on an estimation of “network contention”, the simultaneity of traffic flows contending for a network port. Our system employs a set of counters which track the demand for each output port. This exploits path diversity thanks to earlier detection of adversarial traffic patterns, and decouples buffer size and queue occupancy from contention detection. We evaluate our mechanism in a Dragonfly network. Our evaluations show this mechanism achieves optimal latency under uniform traffic and similar to best previous routing mechanisms under adversarial patterns, with immediate adaptation to traffic pattern changes

Distributed Adaptive Routing in Communication Networks

In this report, we present a new adaptive multi-flow routing algorithm to select end- to-end paths in packet-switched networks. This algorithm provides provable optimality guarantees in the following game theoretic sense: The network configuration converges to a configuration arbitrarily close to a pure Nash equilibrium. In this context, a Nash equilibrium is a configuration in which no flow can improve its end-to-end delay by changing its network path. This algorithm has several robustness properties making it suitable for real-life usage: it is robust to measurement errors, outdated information and clocks desynchronization. Furthermore, it is only based on local information and only takes local decisions, making it suitable for a distributed implementation. Our SDN-based proof-of-concept is built as an Openflow controller. We set up an emulation platform based on Mininet to test the behavior of our proof-of-concept implementation in several scenarios. Although real-world conditions do not conform exactly to the theoretical model, all experiments exhibit satisfying behavior, in accordance with the theoretical predictions