CHAMELEON - A System for Adaptive QoS Provisioning BY Rajesh Krishna Balan A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF SCIENCE DEPARTMENT OF COMPUTER SCIENCE, SCHOOL OF COMPUTING NATIONAL UNIVERSITY OF SINGAPORE 2000 CHAMELEON - A System for Adaptive QoS Provisioning Table of Contents Table of Contents TABLE OF CONTENTS..................................................................................................................2 LIST OF FIGURES..........................................................................................................................5 LIST OF TABLES............................................................................................................................7 LIST OF ABBREVIATIONS...........................................................................................................8 ACKNOWLEDGEMENTS..............................................................................................................9 SUMMARY ....................................................................................................................................10 1 INTRODUCTION .................................................................................................................11 1.1 OBJECTIVES OF WORK......................................................................................................15 1.2 RELATED WORK..............................................................................................................15 1.3 ORGANISATION OF THESIS ...............................................................................................17 2 TRAFFIC GENERATION....................................................................................................18 2.1 NEED FOR REALISTIC TRAFFIC GENERATORS ....................................................................18 2.2 HARDWARE TRAFFIC GENERATORS ..................................................................................20 2.2.1 Hewlett Packard Broadband Series Test System.........................................................20 2.2.2 Adtech AX/4000 Max 1 Gbps Generator / Analyser ...................................................21 2.2.3 QosNetics QA Robot System .....................................................................................21 2.2.4 GN Nettest interWATCH 95000 .................................................................................22 2.2.5 Netcom Systems SmartBits .........................................................................................22 2.2.6 Wendell and Goltermann Domino Gigabit Internetwork Analyser..............................23 2.3 SOFTWARE TRAFFIC GENERATORS ...................................................................................23 2.3.1 Ttcp ...........................................................................................................................23 2.3.2 Iperf...........................................................................................................................24 2.3.3 Surge .........................................................................................................................24 Page 2 of 2 CHAMELEON - A System for Adaptive QoS Provisioning Table of Contents 2.3.4 IPB ............................................................................................................................25 2.3.5 AB .............................................................................................................................25 2.3.6 TCPLIB .....................................................................................................................26 2.3.7 TG .............................................................................................................................26 2.3.8 NETPERF..................................................................................................................27 2.3.9 NETSPEC..................................................................................................................27 2.3.10 Rtpplay and Rtpdump............................................................................................28 2.3 SUMMARY.......................................................................................................................28 3 TCP TUNNELS .....................................................................................................................30 3.1 EXPERIMENTAL SETUP.....................................................................................................31 3.2 PROTECTION OF TCP BULK FLOWS FROM UNRESPONSIVE UDP FLOWS................................32 3.3 PROTECTION OF INTERACTIVE TRAFFIC OVER CONGESTED LINKS.......................................33 3.4 PROTECTION OF “TCP FRIENDLY” FLOWS........................................................................33 3.5 PROTECTION FROM FRAGMENTATION ...............................................................................34 3.6 AGGREGATION OF FLOWS.................................................................................................35 3.7 SHORTENING OF ROUTER QUEUE LENGTHS.......................................................................36 3.8 BACK-PRESSURE EFFECTS OF TCP TUNNELS ....................................................................37 3.9 AVOIDING CONGESTION COLLAPSE ..................................................................................39 3.10 ACTING AS A RELIABLE DATA LINK LAYER.........................................................................39 3.11 USEFULNESS OF TUNNELS ................................................................................................42 3.12 SUMMARY.......................................................................................................................42 4 CHAMELEON SYSTEM .....................................................................................................44 4.1 ADMISSION CONTROL......................................................................................................47 4.2 TRAFFIC MANAGEMENT...................................................................................................48 4.2.1 Adaptive Nature of Chameleon ..................................................................................49 4.3 SYSTEM IMPLEMENTATION ..............................................................................................50 4.3.1 Traffic Management Mechanism................................................................................50 4.3.2 TCP Tunnels Mechanisms..........................................................................................51 Page 3 of 3 CHAMELEON - A System for Adaptive QoS Provisioning Table of Contents 4.4 SYSTEM DEPLOYMENT AND SETUP ...................................................................................55 4.5 LIMITATIONS OF THE SYSTEM...........................................................................................57 5 EXPERIMENTAL RESULTS ..............................................................................................59 5.1 EXPERIMENTAL SETUP.....................................................................................................60 5.2 TRAFFIC MIX OF EXPERIMENTS .........................................................................................61 5.3 TCP BULK SOURCES........................................................................................................62 5.4 TCP INTERACTIVE SOURCES............................................................................................63 5.5 UDP SOURCES ................................................................................................................66 5.6 ADAPTIVE NATURE OF CHAMELEON..................................................................................67 5.7 CHAMELEON AS A RELIABLE AND EFFECTIVE DATA-LINK LAYER .........................................69 5.7.1 Random Single Packet Errors....................................................................................71 5.7.2 Burst Errors...............................................................................................................72 6 SUMMARY AND FUTURE WORK....................................................................................75 6.1 FUTURE WORK ................................................................................................................75 6.2 SUMMARY.......................................................................................................................77 REFERENCES ...............................................................................................................................79 APPENDIX 1 :- TRAFFIC MANAGEMENT (TC) SCRIPTS......................................................85 APPENDIX 2 :- TCP TUNNEL SOFTWARE...............................................................................86 TCP TUNNEL SENDER SOFTWARE..................................................................................................86 TCP TUNNEL RECEIVER SOFTWARE...............................................................................................98 APPENDIX 3 :- TCP-TRUNKING TESTBED SETUP ..............................................................102 Page 4 of 4 CHAMELEON - A System for Adaptive QoS Provisioning List of Figures List of Figures FIGURE 1 : LOGICAL REPRESENTATION OF CHAMELEON 13 FIGURE 2 : TCP TUNNELS 31 FIGURE 3 : INSTANTANEOUS QUEUE OCCUPANCIES FOR CORE ROUTER WITH AND WITHOUT TCP TUNNELS