Wai Sum Lai

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This paper and its part I (link aggregation) companion 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 this paper, use of PNNI node aggregation for new node additions is examined. Two techniques are compared: simple and complex node(More)
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(More)
Private Network-Network Interface (PNNI) is a routing protocol standard developed by the ATM Forum for the connection-oriented ATM networking technology. Open Shortest Path First (OSPF) and Border Gateway Protocol (BGP) are the corresponding IETF standards for connectionless IP networks. In this paper, we compare the hierarchical routing properties of these(More)
We present a graph-theoretic model of routing hierarchies that abstracts the generic properties of standard routing protocols such as PNNI and OSPF/BGP. These protocols are currently deployed in operational networks. Our model is based on purely topological constructs, without referring to protocol details. Through graph partitioning and refinements, a(More)