Circuit planning tool over heterogeneous networks

Currently, there is no existing solution or tool to efficiently route a high-speed circuit over heterogeneous DWDM networks under multi-vendor environment, although each vendor may provide a planning tool to route a circuit within its own sub-network domain. This is mainly due to the lack of common technology for optical reachability calculation across vendor sub-networks. Each sub-network has its own proprietary parameters or formulas to calculate whether an optical path is reachable or not. To route a circuit across heterogeneous networks, we rely on the common function provided by each vendor tool to determine all reachable paths within each sub-network, i.e, the reachability matrix for each sub-network. Here reachability matrix is defined as a list of all reachable paths within the sub-network. Then we build a weighted cost graph based on the reachability matrices and apply the shortest path algorithm to find a cost efficient route. Finally we address the DWDM (Dense Wavelength Division Multiplex) sub-network selection, regenerator placement, and wavelength assignment on the selected route. The systematical methodology has been implemented in a circuit planning tool for high-speed circuits (up to 100Gbps) and used in a real heterogeneous DWDM network since 2009.