Real-time communication in integrated services packet networks.

REAL-TIME COMMUNICATION IN INTEGRATED SERVICES PACKET NETWORKS by Seok-Kyu Kweon Chair: Kang G. Shin One of the main issues in Integrated Services Packet Networks (ISPNs) is providing perconnection Quality-of-Service (QoS) in the heterogeneous tra c environment. To this end, many technical problems such as packet scheduling, resource reservation, tra c policing, and QoS routing must be resolved. In this dissertation, we provide solutions to these problems. We propose a new cell-multiplexing scheme, named TCRM, which provides per-connection delay guarantees in an ATM network. By guaranteeing a minimum throughput, TCRM can provide deterministic delay guarantees under the leaky bucket constraint of input tra c. A scalable implementation of TCRM is presented. In addition to deterministic delay guarantees, TCRM can be used to provide statistical delay guarantees by statistically multiplexing di erent real-time connections onto a single virtual channel. Such statistical multiplexing enhances network utilization. Using a histogram-based source model, we investigate the cell loss/delay characteristics of this approach. Since a large portion of the end users are connected to ISPNs via Ethernets, providing QoS guarantees over Ethernet is important. To this end, we model the MAC protocol of Ethernet with its collision resolution protocol using a Semi-Markov Poisson process. We derive a connection admission control for statistically bounding the medium access time. Video-on-Demand service requires delivery delay guarantees unlike non-real-time applications, but its delay requirement is not as tight as real-time applications. We propose a new service category, called the semi-real-time class for such applications, and present the network control functions necessary for it. For the source tra c characterization necessary to support the semi-real-time class, we de ne and derive a statistical tra c envelope. For e cient QoS routing, we propose a ooding-based QoS route selection algorithm. It not only dramatically reduces message overhead and operational cost, but also provides good performance compared to existing QoS-routing schemes based on either request ooding or link-state dissemination. The overhead is reduced by limiting the search area within which connection-request messages are ooded using a topological information kept at local nodes. c Seok-Kyu Kweon 1998 All Rights Reserved To My Parents and Eunchong ii ACKNOWLEDGEMENTS I would like to thank all those who have contributed, both directly and indirectly, to this dissertation. My deepest gratitude is to my advisor Professor Kang G. Shin for his guidance throughout the course of this work. He allowed me to pursue my own research interests, and was available to discuss my problems and provide feedback. I would also like to thank the members of my dissertation committee, Wayne Stark, Toby Teorey, Farnam Jahanian, and Kimberly Wasserman for their constructive comments and suggestions. Thanks also go to the former and present members of the Real-Time Computing Laboratory, especially, Qin Zheng, Chi-Che Chou, Jennifer Rexford, Atri Indiresan, Emmanuel Abram-Profeta, Seungjae Han, Sunghyun Choi, and Sunghwan Moon for their friendship and insightful discussions. I also appreciate the nancial support during the course of my Ph.D. program by the Korean government, the O ce of Naval Research, and the National Science Foundation. Finally, I thank my parents and my wife, Eunchong, for their dedicated support and love. iii TABLE OF CONTENTS DEDICATION . ii ACKNOWLEDGEMENTS . iii LIST OF TABLES . vii LIST OF FIGURES . viii LIST OF APPENDICES . x CHAPTERS