Please use this identifier to cite or link to this item: http://hdl.handle.net/1783.1/2599

Scheduling optical packet switches with reconfiguration delay

Authors Li, Xin
Issue Date 2005
Summary Using optical technology for the design of high-performance packet switches offers several advantages such as scalability, high bandwidth, lower power con-sumption, and reduction in cost. However, reconfiguring the optical fabric of these switches requires significant time using current technology (micro-electro-mechanical system MEMS, tunable elements, bubble switches, etc.) . As a result, conventional slot-by-slot scheduling may severely cripple the performance of these optical switches due to the frequent fabric reconfiguration that it may entail. This thesis undertakes a comprehensive study on the scheduling of optical packet switches with reconfiguration delay. We consider the scheduling of both synchronous and asynchronous optical fabrics, working with unicast or multicast traffic. The general solution is to reduce the scheduling rate to compensate for the reconfiguration delay. The scheduling problems for both synchronous and asynchronous optical fabrics are formally defined and proven to be NP-hard. As a result, efficient heuristic scheduling algorithms are proposed for both types of fabrics. Specifically, a burst scheduling approach and a self-adjustable time slot assignment (TSA) approach are suggested for synchronous fabric scheduling. On the other hand, a non-preemptive dense scheduling approach is proposed when the fabric is asynchronous. All of the proposed algorithms are shown to achieve 100% throughput under different unicast traffic patterns. In addition, a multi-rack switch architecture with passive optical fabric and active local crossbars is proposed and evaluated for multicast traffic. It makes good use of the available switching capacity and is practical to be implemented using current technology.
Note Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005
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Language English
Format Thesis
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