A heuristic with bounded guarantee to compute diverse paths under shared protection in WDM mesh networks

Abstract

Abstract-Establishing a fault-tolerant connection in a network involves computation of diverse working and protection paths. The Shared Risk Link Group (SRLG) [1] concept is used to model several types of failure conditions such as link, node, fiber conduit, etc. In this work we focus on the problem of computing optimal SRLG/link diverse paths under shared protection. Shared protection technique improves network resource utilization by allowing protection paths of multiple connections to share resources. In this work we propose an iterative heuristic for computing SRLG/link diverse paths. We present a method to calculate a quantitative measure that provides a bounded guarantee on the optimality of the diverse paths computed by the heuristic. The experimental results on computing link diverse paths show that our proposed heuristic is efficient in terms of number of iterations required (time taken) to compute diverse paths when compared to other previously proposed heuristics.

An exact method for constructing minimal cost/minimal SRLG spanning trees over optical networks

“…The work [15] proposes an exact algorithm for calculating SRLG diverse path pairs by decreasing order of the total cost of the paths, including the possibility of inclusion of path length constraints; this is based on an exact algorithm for calculating bi-criteria shortest pairs of disjoint paths in [16]. In [17] a heuristic for solving the problem of calculating 'optimal SRLG/link diverse paths under shared protection' in WDM networks (where the optimality under shared protection is asymmetrically-weighted, as defined in [18]), is proposed. An algorithm based on the algorithm CoSE, in [11], for solving the min-sum SRLG diverse routing problem, enabling the calculation of an extremely high percentage of optimal solutions in short times, is proposed in [19].…”

SRLG failure-disjoint path pair of min-sum cost in GMPLS networks

“…The experimental results presented in [8] show that CoSE-MS is a good compromise between the quality of the obtained solutions and the used CPU time. In [9] an heuristic for solving the problem of calculating optimal SRLG/link diverse paths with shared protection is proposed (it considers the definition of an optimal SRLG diverse path pair with shared protection as asymmetrically-weighted -see [10]). The problem of path protection in wavelength-routed networks with SRLGs is addressed in [11], [12], where an heuristic is proposed and compared with the Trap Avoidance (TA) algorithm [13].…”

Resilient routing in optical networks using SRLG-disjoint path pairs of min-sum cost

“…Assuming that no bandwidth sharing is allowed among protection paths, this problem is designated as the min-sum problem. When bandwidth sharing is allowed among protection paths, this problem can be approached as an asymmetrically weighted pair of disjoint paths [13,23]. When the objective is to obtain the shortest AP (considering that this path will define the QoS of the traffic flow most of the time) that may be protected, the problem is designated as the min-min problem.…”