Optical Switching and Networking 2 (2005) 19–33 www.elsevier.com/locate/osn Physical layer performance benchmarking of two metropolitan area network configurations S. Sygletos a,∗ , C. Skoufis a , C. Matrakidis a , A. Stavdas b , N. LeSauze c , D. Chiaroni c a Institute of Communication and Computer Systems, National Technical University of Athens, Athens, Greece b Department ofTelecommunications Science and Technology, University of Peloponnese, Tripolis, Greece c Alcatel CIT, Research and Innovation, Route de Nozay, Marcoussis, France Received 22 July 2004; received in revised form 22 December 2004; accepted 13 January 2005 Available online 4 March 2005 Abstract The current downturn in the telecommunications sector is imposing a major rethinking as regards the objectives and introductory time frame of optical networking. This is even truer in cost-sensitive segments like metropolitan networks. All- optical solutions will be introduced in a step-by-step approach and the intermediate stages need to be carefully thought out and planned in advance. In this work, two MAN solutions – one short term one using mature technologies and one longer term one using advanced ones – are benchmarked with respect to their physical layer performance. Subsequent variants of the baseline configuration deploying fewer and/or less demanding/lower performance components and subsystems are assessed to identify the trade-offs between performance and cost. It is shown via simulations that a metropolitan network of 1.28 Tb/s capacity can be constructed using four rings of 320 Gb/s capacity each. The geographic extension of such a ring could span up to 160 km with both solutions. It is also demonstrated that the technologically advanced solution is more robust when components with realistic performance are taken into account while it is able to cover a wider geographic range. © 2005 Elsevier B.V. All rights reserved. Keywords: Optical packet switching; Dynamically reconfigurable networks; Wavelength division multiplexing (WDM); Metropolitan area networks (MANs); Physical layer modelling 1. Introduction The emergence of data-centric networking man- dates a paradigm shift in telecommunications en- gineering. In the new era, higher functionality is ∗ Corresponding author. E-mail addresses: ssygl@telecom.ntua.gr (S. Sygletos), astavdas@uop.gr (A. Stavdas). 1573-4277/$ - see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.osn.2005.01.001 delegated to the optical layer in order to provide both dynamic reconfigurability and transparent transporta- tion at wavelength and sub-wavelength level. These characteristics are important for future Metropolitan- Area Networks (MANs), to simultaneously support capacities ranging from sub-Tb/s to multi-Tb/s whilst providing statistical multiplexing directly in the opti- cal layer. The latter requirement stems from the wish