John S. Crawford

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This paper introduces a flexible new method of constructing hierarchical multicast structures suitable for supporting large-scale GRID applications. Hierarchical multicast trees are constructed by repeated application of clustering algorithms that partition the members of a large application community to form a layered hierarchy of clusters of users. The(More)
Conventional delivery mechanisms for many-to-many multicast services consider either a single shared tree or a source rooted trees approach. These two mechanisms complement each other in terms of performance and protocol complexity. In this paper, we describe a design that uses multiple shared trees that would provide a balance between these two extreme(More)
We study decentralised low delay degree-constrained overlay multicast tree construction for single source real-time applications. This optimisation problem is NP-hard even if computed centrally. We identify two problems in traditional distributed solutions, namely the greedy problem and delay-cost trade-off. By offering solutions to these problems, we(More)
An increasing number of networking applications involve m ul-tiple participants and are therefore best supported by m ulticasting. Where a m ulticast application consumes high bandwidth, it is important to min-imise the eeect on the network by oering economical multicast routes. Many new applications made possible by n e t works based on ATM involve(More)
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