or offline. For offline schedul- ing, consult T. Rodeheffer and J. Saxe's "Smooth Scheduling in a Cell-Based Switching Network," where QoS guarantees are addressed. Other good sources on the same subject are M. Bonuccelli's "Incremental Time-Slot Assignment in SS/TDMA Satellite Systems," I. Gopal's "Minimizing Packet Waiting Time in a Multibeam Satellite System," and T. Inukai's "An Efficient SS/TDMA Time Slot Assignment Algorithm." The latter reference is still very applicable although it is quite old. For online scheduling, the article "Two-Dimensional Round-Robin Schedulers for Packet Switches with Multiple Input Queues" by R. LaMaire and D. Serpanos discusses a two-dimensional round-robin approach, whereas some of the work from Nick McKeown's Stanford team on iSLIP and Tiny Tera can be found in "Designing and Implementing a Fast Crossbar Scheduler," "Tiny Tera: A Packet Switch Core," "The iSLIP Scheduling Algorithm for Input-Queued Switches." D. Serpanos and P. Antoniadis' article "FIRM" and Anthony Kam and Kai-Yeung Siu's article "Linear-Complexity Algorithms for QoS Support in Input Queued Switches with No Speedup" dis- cuss scheduling when confronted with multiple input queues, the latter with QoS guarantees. Regarding a sensitive speed-up requirement issue that pops up in implementations when emulat- ing output queuing, the article "Analysis of a Packet Switch with Memories Running Slower Than the Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. SWITCH FABRICS SWITCH FABRICS Line Rate" by S. Iyer provides the context background. Articles written by P. Krishna et al., Chuang et al., and S. Iyer and N. McKeown elaborate on several approaches to tackle it. For coverage of switch fabric topologies, take a look at the paper "The Theory of Connecting Networks and Their Complexity" by M. Marcus. In the book Gigabit Networking, C. Partridge C