Topology Aggregation in PNNI Networks Part I: Link Aggregation

This paper and its sequel in Part II (Node Aggregation) present our work done in the deployment of topology aggregation techniques in the layer 2 infrastructure of AT&T's Global Network to deal with network growth. In Part I, use of PNNI link aggregation for new border-link additions is examined. This will cause an information loss with some impacts on routing. However, by aggregating multiple parallel border links between the same office pair, scaling in a large network can be achieved without compromising latency performance.