A joint working and protection path selection approach in WDM optical networks
نویسندگان
چکیده
In survivable WDM optical networks, one of the critical issues is route computation. Although there is a possibility to optimize the route computation (together with the wavelength assignment) for static traffic pattern, it is impossible to perform such optimization for incremental and dynamic traffic. The conventional approach first computes the working path and then computes an edge-disjoint protection path using the shared risk link groups (SRLGs) information of the working path. In this paper, we propose a joint working and protection path selection approach. Our approach tries to find multiple pairs of candidate working and protection paths. Then the pair with the minimum cost sum is selected. We have evaluated the performance benefit gained from the joint path selection approach with a single service class dynamic traffic supporting 1:1 protection scheme. I INTRODUCTION In WDM optical networks, one of the critical issues is path computation and selection to provide the survivability. For static traffic pattern (traffic arriving all at once), there are many studies in the literature to optimize the network resource utilization, such as linear programming. However, for incremental (no lightpath teardown) and dynamic traffic pattern, there is no such optimization approach. In [1], an approach is proposed to address the route and wavelength selection for incremental traffic. For dynamic traffic, generally, the working path is computed first and then the SRLGs information of the working path are built [2]. An edge-disjoint path is then selected as the protection path using the SRLGs information. The route computation of working and protection path is generally based on the shortest path first (SPF) algorithm, with the constraints-based routing extension. This approach does not consider any optimization at all. It only attempts to find a best (lowest cost) path in each route computation. However, there is one possibility to perform a limited optimization for the dynamic traffic. Although the global optimization for all calls is impossible, we can perform the individual optimization for the working and protection path of each new call request. In this paper, we propose an approach to select the working and protection paths so as to minimize the cost sum of both. The rest of this paper is organized as follows. In section II, we describe our joint path selection approach for working and protection paths. In section III, we discuss the cost function of a link and a path respectively. In section IV, the emulation environment and …
منابع مشابه
A Novel Protection Guaranteed, Quality of Transmission Aware Routing and Wavelength Assignment Algorithm for All-optical Networks
Transparent All Optical Networks carry huge traffic and any link failure can cause the loss of gigabits of data; hence protection and its guarantee becomes necessary at the time of failure. Many protection schemes were presented in the literature, but none of them speaks about protection guarantee. Also, in all optical networks, due to absence of regeneration capabilities, the physical layer i...
متن کاملExtension of segment protection for bandwidth efficiency and differentiated quality of protection in optical/MPLS networks
This paper investigates the problem of dynamic survivable lightpath provisioning against single node/link failures in optical mesh networks employing wavelength-division multiplexing (WDM). We unify various forms of segment protection into generalized segment protection (GSP). In GSP, the working path of a lightpath is divided into multiple overlapping working segments, each of which is protect...
متن کاملOn the Complexity of Computing Least Cost Disjoint Path Pair with Dependent Cost Structure in Optical Networks
In an optical wavelength division multiplexing (WDM) network establishing a survivable connection involves computation of least cost disjoint (working and protection) paths. In this work we study the problem of computing edge/node disjoint path pair in WDM networks with full wavelength converters for providing shared protection. To enable greater resource sharing among protection paths we intro...
متن کاملResource-efficient path-protection schemes and online selection of routes in reliable WDM networks
The optimal choice of routing and wavelength assignment (RWA) for the working and protection path–pair of the newly generated demand request is often a complex problem in reliable wavelength-division-multiplexed (WDM) networks subject to dynamic traffic. The challenge is twofold: how to provide the required reliability level without over-reserving network resources and how to find a good soluti...
متن کاملPerformance Evaluation of Efficient Shared Path Protection in Mesh WDM Networks
The efficient use of network capacity in shared restoration schemes strongly depends upon the path selection procedure. In this paper we propose and evaluate efficient shared path selection algorithms for restoration of connections in optical networks. Namely, two distributed path selection algorithms are proposed. The first approach maintains global information on network resource usage to det...
متن کامل