Software tools for a multilayer network design

Today's long haul and metro high-speed networks are mainly based on synchronous digital hierarchy (SDH) or its American equivalent synchronous optical network (SONET) and wavelength division multiplex (WDM). On the other hand, the large amount of traffic growth during the last years has been caused mainly by Internet protocol (IP) traffic. Traditionally, the IP-router based networks and the cross-connect based synchronous networks are often planned and operated separately. However, in line with new developments such as generalized multiprotocol label switching (GMPLS), network providers begin to realize that the convergence of these two worlds promises significant benefits. A set of software tools to support the network designer has been developed and used on various kinds of real world network planning problems arising in the SDH/WDM context. This includes, among others, 1+1 protection planning, static restoration and dual homing issues. These tools are extended with additional features to handle aspects of the IP/SDH interplay in a GMPLS environment. The two main components are an AMPL based integer model (solved via CPLEX) and a heuristic implemented in C++.