Performance analysis of PNNI routing in ATM networks: hierarchical reduced load approximation

We investigate the performance issue of PNNI (private network-to-network interface) routing for ATM networks. An introduction to PNNI routing protocol is given. We extend the reduced load approximation algorithm to ATM networks with PNNI routing. A hierarchical reduced load approximation scheme is proposed. The scheme includes two steps: the reduced load approximation algorithm is first applied on the aggregated network at the upper level; then the approximation is refined at the lower level as needed using the results from the upper level. This hierarchical scheme follows the PNNI routing framework and results a fast and scaleable algorithm.