Nico Wauters

Design of the optical path layer in multiwavelength cross-connected networks

We discuss the wavelength requirement for optical networks based on wavelength-division multiplexing (WDM). A mathematical model, to represent the routing and wavelength assignment in optical networks with or without wavelength conversion, is described, and metrics are defined to express the performance. A new heuristic for routing and wavelength assignment is proposed and compared with the Dijkstra algorithm and with a solution based on integer linear programming. The different techniques are applied to a variety of network examples with different traffic loads.

Study on the Implementation of Optical Transparent Transport Networks in the European Environment—Results of the Research Project COST 239

This paper reports the main results obtained in the framework of the COST239 project on the implementation of transparent optical network schemes to connect main European cities. The investigation on transmission limitations has shown that transmission systems, for which 1662:5 Gbit/s WDM systems are used due to traf®c reasons, have a maximum range shorter than 1000 km. This condition does not allow a completely transparent network. Two solutions, the partitioned and the gridconnected network architecture, are proposed, described, and compared in the paper.

The IP/MPLS over ASON/GMPLS test bed of the IST project LION

A test-bed of a multi-vendor IP/MPLS over ASON/GMPLS network has been realized integrating IP Gigabit routers and optical equipment in a managed multi-domain environment to investigate the realization of soft-permanent optical connections and multi-layer resilience strategies

Reduction of wavelength blocking through partitioning with wavelength convertors

Wavelength translation is still a controversial subject in the optical network research world. From simulation results of different groups we may, however, conclude that the increased management complexity, if no wavelength translators are used, may be a stronger point to justify wavelength translation than the performance increase, which is relatively small. Most of the performance comparisons between wavelength translated networks [with virtual wavelength paths (VWP)] and wavelength routed networks [with wavelength paths (WP)] done so far assume a fixed traffic matrix.

Multilayer resilience tests in an IP over optical switched test-bed in IST project LION

This paper presents experimental results of a multilayer recovery test-bed involving the combination of optical restoration and MPLS Fast Reroute recovery techniques. This experiment has been conducted in the context of the European IST-project LION.