PANEL - Protection Across NEtwork Layers

The integration of different transport network technologies requires a better coordination between network layers such as ATM, SDH and WDM. This paper addresses specifically the problem of interaction mechanisms between multiple layers in order to improve the overall network reliability. Various parameters defined by the operators have to be taken into account such as : survivability, availability, serveability. In order to develop new interaction strategies, a detailed knowledge is required on the fault propagation and on the recovery mechanisms available in the individual layers. From this, interaction strategies can be developed which have to be supported by detailed simulations in order to obtain a better understanding of their operation and performance. The goal of the interaction between the different layers is not only the improvement of the overall network reliability but as well the reduction of the overall network cost. This requires however also an integrated multilayer approach for the network planning. These aspects are addressed by the ACTS project PANEL (Protection Across NEtwork Layers) and are discussed in this paper. They are split in 4 activities covering the work on operator requirements, interworking concepts and protocols, simulation of the recovery mechanism and multilayer network planning.