Minimizing request blocking in all-optical rings

Nomikos, C; Pagourtzis, A; Zachos, S

dc.contributor.author	Nomikos, C	en
dc.contributor.author	Pagourtzis, A	en
dc.contributor.author	Zachos, S	en
dc.date.accessioned	2014-03-01T02:42:17Z
dc.date.available	2014-03-01T02:42:17Z
dc.date.issued	2003	en
dc.identifier.issn	0743166X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/30914
dc.subject	All Optical Network	en
dc.subject	Approximate Algorithm	en
dc.subject	Disjoint Paths	en
dc.subject	Matching Method	en
dc.subject	Routing and Wavelength Assignment	en
dc.subject	Satisfiability	en
dc.subject.other	Algorithms	en
dc.subject.other	Approximation theory	en
dc.subject.other	Bandwidth	en
dc.subject.other	Iterative methods	en
dc.subject.other	Routers	en
dc.subject.other	Wavelength division multiplexing	en
dc.subject.other	All optical networks	en
dc.subject.other	Optical communication	en
dc.title	Minimizing request blocking in all-optical rings	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1109/INFCOM.2003.1208971	en
heal.identifier.secondary	http://dx.doi.org/10.1109/INFCOM.2003.1208971	en
heal.publicationDate	2003	en
heal.abstract	In all-optical networks that use WDM technology it is often the case that several communication requests have to be blocked, due to bandwidth and technology limitations. Minimizing request blocking is therefore an important task calling for algorithmic techniques for efficient routing and wavelength assignment. Here we study the problem for rings under both the undirected and the directed settings, corresponding to symmetric and one-way communication respectively. The problem in graph-theoretic terms can be formulated as the MAXIMUM ROUTING AND PATH COLORING PROBLEM. We present a Chain-and-Matching technique for routing requests and coloring the corresponding paths which gives constant approximations for both the undirected and the directed cases. For the undirected problem we obtain a 2/3-approximation algorithm; this corresponds to a considerable increase in the number of satisfied requests compared to the best known algorithm so far, due to Wan and Liu [1], that achieves a 1 - 1/e ratio using iteratively a maximum edge-disjoint paths algorithm. For the directed case, we also introduce a Balanced Matching method which, combined with the Chain-and-Matching technique, gives a 7/11-approximation algorithm. This algorithm also improves upon the (1 - 1/e)-approximation algorithm that can be obtained by extending the iterative method of [1].	en
heal.journalName	Proceedings - IEEE INFOCOM	en
dc.identifier.doi	10.1109/INFCOM.2003.1208971	en
dc.identifier.volume	2	en
dc.identifier.spage	1355	en
dc.identifier.epage	1361	en