Dynamic lightpath protection in WDM mesh networks under wavelength-continuity and risk-disjoint constraints

• Published in: Computer networks (Amsterdam, Netherlands : 1999) Vol. 48; no. 2; pp. 91 - 112
• Main Authors: Yuan, Shengli, Jue, Jason P.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 06.06.2005; Elsevier Science; Elsevier Sequoia S.A
• Subjects: Algorithms; Applied sciences; Computer networks; Exact sciences and technology; Operation, maintenance, reliability; Optical fiber communications; Optical telecommunications; Path protection; Risk disjoint; Shared risk link group; Studies; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Wave division multiplexing; Wavelength continuity constraint; Wavelength-division multiplexing (WDM) networks; Risk disjoint; Path protection; Shared risk link group; Wavelength-division multiplexing (WDM) networks; Wavelength continuity constraint; Performance evaluation; Optical links; Meshed network; Computer simulation; Optical telecommunication; Wavelength division multiplexing; Polynomial method; Lightpath protection; Algorithm; Polynomial time; Integer programming; Optical fiber network; Heuristic method; Telecommunication network; NP complete problem; Optical fiber communication; Service quality; Optical fiber
• ISSN: 1389-1286; 1872-7069
• DOI: 10.1016/j.comnet.2004.10.013

Path protection requires finding a working path and a protection path that are link disjoint. In this paper, we consider two fundamental problems on dynamic lightpath protection in WDM mesh networks. In the first problem, we consider a network without wavelength converters; thus both the working lightpath and protection lightpath are subject to the wavelength continuity constraint. Existing polynomial time algorithms can be applied to find a pair of link-disjoint lightpaths on a single wavelength; however, such algorithms fail if the working and protection lightpaths are on two different wavelengths. In the second problem, we consider a network with full wavelength conversion; thus the wavelength continuity constraint does not apply. Yet a single factor can cause multiple fiber links to fail simultaneously. The problem becomes finding link-disjoint lightpaths that are also risk disjoint. We prove that both of the two problems are NP-complete. We develop ILP formulations and heuristic algorithms for the two NP-complete problems. Practical constraints such as service level agreement (SLA) and priority are also considered. Computer simulations are conducted to evaluate the performance of the heuristic algorithms.