Squeezed Protection in Elastic Optical Networks Subject to Multiple Link Failures

Abstract

<div>Elastic optical network (EON) is fast becoming a key solution for designing optical network with better usage of spectrum resources or other objectives of interest to tenant and/or operators. A primary concern of EONs is to protect the network against failures of its elements, because this kind of event can provoke the loss of substantial amount of traffic. In this paper, we propose a new mixed integer linear programming (MILP) formulation for protecting the network traffic against multiple link failures. The key idea is to use bandwidth squeezing together with grooming capability to provide few extra traffic for protection and guarantee a minimum bandwidth for each source–destination node pair under multiple failure events. The proposed formulation solves the virtual topology design problem jointly with the grooming, routing, modulation and spectrum allocation (RMSA) tasks. Due to the non-deterministic polynomial time (NP-hard) nature of the proposed MILP formulation, a heuristic strategy (referred to as two-step MILP) for large networks is also proposed. The solutions and performance of the proposed MILP formulation and two-step MILP analyzed through case studies in a small network. In addition, the performance of three large networks is assessed for cases scenarios where connections are under different service-level agreement (SLA). In view of proposed formulation and two-step MILP, it is possible to identify the configurations that ensure better usage of spectrum resources with different kinds of protection against single or multiple link failures.</div>

Guest Editors’ Introduction: Special Section on Design and Management of Reliable Communication Networks

“…In [11], the authors explore new design methodologies (as cooperative storage, content replication and multipath routing) to ensure EON survivability in extreme circumstances including disaster events generating multiple and correlated network failures. Specific solutions for protection in EON are investigated also in [12], where the authors investigate the concept of bandwidth squeezing (i.e., providing less data rate to backup paths) together with grooming capability to provide protection under multiple failure events. Finally, in [13], the authors investigate how to perform early soft-failure detection, identification and localization based on the observation of the temporal behavior of Quality of Transmission measures including noise figure in optical amplifiers and reduced signal to noise ratio in wavelength selective switches.…”