Heuristic Solution to Protect Communications in WDM Networks using P-cycles

Optical WDM mesh networks are able to transport huge amount of information. The use of such technology however poses the problem of protection against failures such as fibre cuts. One of the principal methods for link protection used in optical WDM networks is pre-configured protection cycle (p-cycle). The major problem of this method of protection resides in finding the optimal set of p-cycles which protect the network for a given distribution of working capacity. Existing heuristics generate a large set of p-cycle candidates which are entirely independent of the network state, and from then the good sub-set of p-cycles which will protect the network is selected. In this paper, we propose a new algorithm of generation of p-cycles based on the incremental aggregation of the shortest cycles. Our generation of p-cycles depends on the state of the network. This enables us to choose an efficient set of p-cycles which will protect the network. The set of p-cycles that we generate is the final set which will protect the network, in other words our heuristic does not go through the additional step of p-cycle selectio

Application-Aware Protection in DWDM Optical Networks

International audienceFast recovery time and reduced resource utilization are the two main criteria for determining the quality of survivability mechanism. Now it is well-known that link-based protection and path-based protection provide respectively a short recovery time and reduced use of resources. To benefit from the both of these saliencies, we propose in this paper to use these mechanisms simultaneously. Indeed, demands mandating shorter recovery time will be protected using link-based protection. Meanwhile other demands will be protected using path-based protection. Simulation results show that the proposed solution achieves a good trade-off between resource utilization and recovery time

Tolérance aux pannes dans les réseaux optiques de type WDM

La tolérance aux pannes est une propriété indispensable des réseaux optiques à cause de la bande passante importante offerte par la technologie WDM (Wavelength Division Multiplexing). La tolérance aux pannes signifie que le réseau a la capacité de maintenir un service acceptable, même si une panne dans le réseau survient. Dans cette thèse, nous étudions la tolérance aux pannes des réseaux optiques. Le travail effectué dans cette thèse s'articule autour de deux grandes parties. La première partie aborde la tolérance aux pannes des réseaux optiques formés d'un domaine unique. Dans cette partie, nous analysons et classons, dans un premier temps, les différents mécanismes proposés dans la littérature pour la protection de ce type de réseau. Dans un deuxième temps, notre étude se focalise sur la protection par p-cycles à cause des avantages offerts par ce mécanisme de protection : faible temps de reprise et bonne utilisation de ressources. La difficulté majeure de ce mécanisme réside dans le calcul de l'ensemble le plus efficace possible de p-cycles protégeant le réseau pour une certaine charge. Pour cela nous proposons une solution pour calculer un ensemble de p-cycles efficace protégeant le réseau, et améliorant les performances des solutions proposées dans la littérature. La première partie de cette thèse est réservée à la tolérance aux pannes d'un domaine simple car elle fait l'hypothèse que chaque noeud dans le réseau possède une vision entière et détaillée de la topologie physique du réseau. Une telle hypothèse n'est plus valide quand il s'agit d'un réseau de taille importante, un réseau multi-domaine par exemple. Très peu d'études scientifiques ont été menées sur la tolérance aux pannes des réseaux multi-domaines. La deuxième partie de cette thèse décrit les travaux actuels portant sur la protection contre les pannes dans les réseaux multi-domaines et propose une comparaison quantitative et qualitative entre les solutions proposées dans la littérature. Nous proposons également une solution qui se base sur la protection par p-cycles et l'agrégation de topologie. Elle surmonte les problèmes des solutions proposées dans la littérature.Survivability in optical network is an important issue due to the huge bandwidth offered by optical technology. Survivability means that the network has the ability to maintain an acceptable service level even after an occurrence of failures within the network. In this thesis, we study the survivability in optical networks. Indeed, our work focuses on two main parts. The first part addresses the survivability in networks composed of one single domain. Firstly, we study and classify the various mechanisms of survivability proposed in the literature. Then we focus on p-cycles design. The major challenge of p-cycle design resides in finding an optimal set of p-cycles protecting the network for a given working capacity. In our thesis we propose a novel heuristic approach, which computes an efficient set of p-cycles protecting the network in one step. Our heuristic approach takes into consideration two main criteria: the redundancy and the number of p-cycles involved in the solution. The mechanisms studied in the first part are typically destined to single-domain protection, because they assume that each node in the network may have a complete vision of the physical topology of the network. Such an assumption is not realistic in the case of large networks, such as a multi-domain networks. Few works have focused on survivability in multi-domain optical networks. The second part of this thesis describes and evaluates existing solutions and compares their performances. We propose also a solution based on p-cycles and topology aggregation which overcomes the different problems of the existing solutions.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

Survivability in multi-domain optical networks using p-cycles

Abstract Survivability is becoming an important issue in optical networks due to the huge bandwidth offered by optical technology. Many works have studied network survivability. The majority of these works are destined for single-domain networks. In this work, we address the survivability of multi-domain optical networks. This paper provides a classification of the existing protection solutions proposed for multi-domain networks and analyses their advantages and limitations. We propose a new solution for multi-domain optical networks based on p-cycles (pre-configured cycles). For scalability and security reasons, we also propose a topology aggregation model adapted to p-cycle computations. This aggregation model allows our proposed solution to find a trade-off between two competing goals: efficient use of backup resources and short running time. Simulation results show that the proposed solution is a good trade-off between resource utilization and running time compared to existing solutions. Keywords Multi-domain · Survivability · p-cycle · Topology aggregation · Optical networ

Graph Partitioning for Survivability in Multi-Domain Optical Networks

As optical networking deployments increase, multi-domain provisioning and survivability are becoming major concerns. A key challenge in multi-domain survivability is the scalability problem. To address this concern, various solutions have already been proposed based upon topology aggregation schemes. However, these mechanisms do not scale well with increasing domain counts and further investigation is required to develop more scalable alternatives. Along these lines, in this paper we propose to use graph partitioning techniques to solve the scalability problem in multi-domain optical networks. To demonstrate the efficiency of our method, we also extend the p-cycle concept to multi-domain settings. Overall simulation results show the efficiency of our proposed solution in terms of resource utilization and the number of p-cycle structures

A Topology Aggregation Model for Survivability in Multi-Domain Optical Networks Using p-Cycles

Abstract—Survivability becomes an important issue in optical networks due to the huge bandwidth offered by optical technology. Many works have studied network survivability. The majority of these works are typically destined to singledomain. In this work we address the survivability in multidomain optical networks. This paper provides a classification of the existing protection solutions proposed for multi-domain networks and analyses their advantages and limitations. We propose a new solution for multi-domain optical networks based on p-cycles. For scalability and security reasons, we also propose a topology aggregation model adapted to the p-cycles computation. This aggregation model allows our proposed solution to find a trade-off between two competing goals: efficient use of backup resources and small running time. Simulation results show that the proposed solution is a good trade-off between resource utilization and running time compared to the existing solutions. Keywords-multi-domain; survivability; p-cycle; topology aggregation; optical network; I

Protection par p-cycles dans les réseaux WDM

National audienceParmi les mécanismes de protection efficaces proposés pour les réseaux optiques, on trouve la protection par cycles préconfigurés ou p-cycles. La difficulté majeure de ce mécanisme réside dans le calcul de l'ensemble le plus efficace possible des p-cycles protégeant le réseau pour une certaine charge. Les solutions existantes génèrent des p-cycles candidats indépendamment de l'état du réseau, puis un sous-ensemble efficace de p-cycles protégeant le trafic du réseau est sélectionné. La solution que nous proposons dans cet article calcule l'ensemble des p-cycles protégeant le réseau sans passer par l'étape de génération de p-cycles candidats. Notre proposition est basée sur l'agrégation incrémentale des cycles en tenant compte de la topologie et de la distribution du trafic dans le réseau. Cela nous permet de calculer l'ensemble des p-cycles en une seule étape et en fonction des besoins

A Survey of Survivability in Multi-Domain Optical Networks

Network survivability is becoming an important issue and a topical subject in WDM optical mesh networks. Many works have studied network survivability. However, few works have focused on survivability in multi-domain optical networks. This paper reviews the literature on survivability against failures in multi-domain optical networks. The main objective of this study is to evaluate and analyze existing solutions and to compare their performance in terms of different criteria: resource utilization, ratio of rejected connections and recovery time