The overall objective of OPTISOFT is the designing and the implementation of a simulation and modeling software tool which aims to the precise designing and analysis of metropolitan optical networks with wavelength multiplexing. The proposed highly specialised software will be based on the results of our research in the development of an integrated simulation methodology of metropolitan optical networks with wavelength multiplexing. The methodology includes both the logical and the natural transport layer of such networks. Such a software is expected to be rendered as a precious tool in the products' production in the continuously developing area of optical telecommunications and in the improvement of processes for designing of appliances, systems and high technology optical fibres networks. It is expected that the proposed tool will help telecommunication companies in their effort to serve the increasing needs of bandwidth. In particular, this project will help the contractor company to be rendered as a pioneer in the area of consulting on optical telecommunications issues. The innovation of this effort consists in that the proposed software is the first of its kind in the world that combines the ability of designing optical networks with vertical integration of the natural and the logical layer of such networks. The software provides efficient modeling of the effects presented in the natural transport layer of optical networks and it supports efficient routing methods. The users of the tool will be able to evaluate the designing of next generation metropolitan optical networks fast, reliably, costlessly and also having the ability to precisely determine the consequences in the performance before the network construction. The project will use literary property of the Contractor in the simulation methodology that can be effectively used for the optical networks designing.