Hamza Drid

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.

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

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.

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.

Multi-criteria p-cycle network design

The major challenge of p-cycle network design resides in finding an optimal set of p-cycles protecting the network for a given working capacity. Existing solutions (exact and heuristic approaches), for solving the problem, find the set of p-cycles protecting the network through two steps: one step for generating candidate p-cycles and a second step for selecting the efficient ones. In this paper, we present 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 different criteria: the redundancy and the number of p-cycles involved in the solution. Simulation study shows that our approach necessitates a lower redundancy and fewer p-cycles to protect the network compared to state-of-the-art approaches.

Survivability in multi-domain optical networks using p-cycles

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.

Upgrading optical networks with elastic transponders

We show how rate-adaptive transponders help reduce the cost of optical networks compared to single and mixed-line-rate solutions through a better ability to accommodate growth of traffic and uncertainties in traffic matrices during network upgrades.

P-cycle design for mixed-line rate optical networks

P-cycle design solutions are mostly limited to fixed-rate optical settings. To handle the increased heterogeneity of emerging optical links, this paper develops and evaluates a new solution for p-cycle design in mixed-line rate optical networks.

Application-aware protection in DWDM optical networks

Fast 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.