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By CARLTON A. THOMPSON a DISSERTATION

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A DESIGN AND PERFORMANCE STUDY OF A DISTRIBUTED IP-BASED TELECOMMUNICATION SYSTEM (D-IPTS) By CARLTON A. THOMPSON A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2016 © 2016 Carlton A. Thompson 2 To my mother Hyacinth Thompson and to the memory of my father Carlton Thompson, for always supporting me during my studies and work. 3 ACKNOWLEDGMENTS The path to PhD has been very challenging and I have achieved a milestone in my career. I learned a lot about the field of IP telecommunications, peformance analysis, and associated qualitative research methods. This dissertation would not have been written without the help of certain individuals. I would like to extend my gratitude towards my advisor Dr. Latchman and co-advisor Dr. McNair. They helped me with the selection of my topic and provided guidance during the writing of my dissertation. Their encouragement and insights have always been inspiring. In addition, none of this could have been possible without my family and loved ones providing their continuous support during my various course studies. Also, I would like to thank my friends and colleagues from the Electrical and Computer Engineering Department at the University of Florida. Finally, I would like to thank Texas Instruments ™ for providing financial support for this work. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS..................................4 LIST OF TABLES......................................9 LIST OF FIGURES..................................... 10 LIST OF ABBREVIATIONS ................................ 14 ABSTRACT......................................... 17 CHAPTER 1 INTRODUCTION .................................... 19 Motivation........................................ 20 Voice Networks..................................... 21 Traditional Telecommunications Networks................... 21 VoIP Networks .................................. 23 VoIP for telephone long distance cost reduction............ 23 VoIP for in-office communication .................... 25 Aims and Objectives.................................. 26 Dissertation Structure ................................. 27 2 BACKGROUND .................................... 29 Overview of Existing and Emerging IP Telecommunications Systems . 29 IP Telecommunications Protocols........................... 31 SCCP Signaling Protocol ............................ 32 IAX Signaling Protocol ............................. 32 SIP Signaling Protocol.............................. 32 SDP Signaling Protocol ............................. 32 Data Transfer Protocols ................................ 33 Real-time Transport Protocol .......................... 33 Resource Reservation Protocol ........................ 33 Real Time Streaming Protocol ......................... 33 Voice Codecs...................................... 33 G.729 ....................................... 34 G.722 ....................................... 35 G.711 ....................................... 35 IP Telecommunications Availability.......................... 36 Availability..................................... 36 Reliability Block Diagram ............................ 38 Performance Measures for IP Telecommunications................. 40 5 Quality of Service................................. 40 Network QoS parameters........................ 40 Measuring VoIP QoE........................... 41 Queuing Theory ................................. 41 Queuing techniques........................... 43 M/G/1 model ............................... 45 Summary..................................... 46 Literature Review.................................... 46 VoIP Overview .................................. 46 System Design.................................. 47 Performance ................................... 48 System Modeling and Reliability ........................ 49 Proprietary Telephone Systems......................... 55 Cisco ................................... 55 ShoreTel ................................. 56 Lync.................................... 57 8x8, Inc................................... 58 Vonage .................................. 60 Next Generation Systems............................ 61 Skype for Business............................ 61 OnSIP................................... 64 2600hz .................................. 66 Summary..................................... 68 3 DETAILED STUDY OF SESSION INITIATION PROTOCOL AND REAL TIME PROTOCOL ...................................... 70 Session Initiation Protocol............................... 70 SDP Signaling Protocol ................................ 73 Real-Time Protocol................................... 74 SIP and RTP Security................................. 75 4 DISTRIBUTED IP TELECOMMUNICATION SYSTEM (D-IPTS) ......... 76 Components of D-IPTS Testbed ........................... 77 Alpine Linux.................................... 78 Kamailio...................................... 79 FreeSWITCH................................... 80 Other Components................................ 83 Web interface............................... 83 DNS server................................ 84 DHCP server............................... 85 Provisioning server............................ 86 D-IPTS Testbed..................................... 87 NATs Solution and Mobility .............................. 90 6 RTPproxy and NAT traversal .......................... 90 Mobility ...................................... 91 D-IPTS Testbed Implementation ........................... 92 Call Flow ..................................... 92 Call Processing.................................. 93 Preliminary Tests................................. 95 High Availability D-IPTS............................. 96 D-IPTS database redundancy...................... 97 D-IPTS DNS failover........................... 98 System Configurations ............................. 98 Multiple server .............................. 98 LXC.................................... 98 Summary........................................100 5 TESTBED PERFORMANCE MODEL DEVELOPMENT AND CAPACITY STUDY 101 Testbed Design.....................................102 SIPp Configuration................................104 Kamailio Software Customization .......................105 Experiment 1: Call Scenarios Testing ........................106 Experiment 2: Kamailio Router Test .........................113 Concurrent calls .................................113 Calls per Second Test ..............................116 Experiment 3: FreeSWITCH Stateful Call Processing . 116 Concurrent Calls Test ..............................117 Calls per Second Test ..............................117 D-IPTS Performance Comparison With Next Generation Systems . 118 Summary........................................119 6 QUEUING MODEL DEVELOPMENT AND VALIDATION .............. 121 Queuing Model.....................................121 Queuing Experiments .................................123 Utilization Comparison/Validation........................126 Calls per Second Comparison/Validation....................126 Waiting Time Comparison/Validation......................127 D-IPTS Design Decisions...............................128 Call Rate and Utilization.............................129 Number of Servers................................130 Summary........................................130 7 CONCLUSION AND FUTURE WORK ........................ 132 7 APPENDIX A SUMMARY OF RESEARCH CONTRIBUTIONS .................. 135 B KAMAILIO INSTALLATION .............................. 137 C FREESWITCH INSTALLATION ............................ 139 D SETTING UP MASTER-SLAVE REPLICATION ................... 140 E SETUP LXC HOST ................................... 144 F CONNECTING TO A WIRELESS ACCESS POINT ................. 148 G BUILD OR COMPILE LINPHONE FROM SOURCE FOR IOS .......... 150 REFERENCES....................................... 152 BIOGRAPHICAL SKETCH ................................ 167 8 LIST OF TABLES Table page 1-1 Cost comparison of IP telecommunications Systems (all prices in USD) [1] . 27 2-1 IP telecommunications codec comparison ................... 34 2-2 Mean Opinion Score ............................... 35 2-3 Downtime for different availabilities ....................... 36 2-4 Inter-arrival time distributions........................... 43 2-5 Queuing service disciplines ........................... 43 2-6 Client and server pricing............................. 57 2-7 CALPricing .................................... 58 2-8 Lync Online USL ................................. 58 2-9 OnSIP calling rates................................ 65 3-1 SIP response codes ............................... 73 5-1 Test computer systems..............................102 5-2 D-IPTS call scenario tests ............................106 6-1 Kamailio call processing Times .........................123 9 LIST OF FIGURES Figure page 1-1 Distributed IP-based Telecommunication System architecture . 21 1-2 PSTN architecture .............................. 22 1-3 VoIP calling using adapter.......................... 24 1-4 Redundancy in a traditional PBX [2]..................... 26 2-1 Packet switching ............................... 31 2-2 A-to-D conversion............................... 34 2-3 System configuration architectures..................... 39 2-4 Combined system configuration architectures............... 39 2-5 Network QoE factors............................. 42 2-6 Queuing Model...............................
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