Economic Analysis of the Cost of Inconsistencies in the Implementation of ISDN Network Layer Standards

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Economic Analysis of the Cost of Inconsistencies in the Implementation of ISDN Network Layer Standards Rochester Institute of Technology RIT Scholar Works Theses 2002 Economic analysis of the cost of inconsistencies in the implementation of ISDN network layer standards Thomas Bennett Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Bennett, Thomas, "Economic analysis of the cost of inconsistencies in the implementation of ISDN network layer standards" (2002). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Economic Analysis of the Cost of Inconsistencies in the Implementation of ISDN Network Layer Standards By Thomas R. Bennett Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Information Technology Rochester Institute of Technology B. Thomas Golisano College of Computing and Information Sciences March 2002 Thesis Reproduction Permission Form Rochester Institute of Technology B. Thomas Golisano College of Computing and Information Sciences Master of Science in Information Technology Economic Analysis of the Cost of Inconsistencies in the Implementation of ISDN Network Layer Standards I, Thomas R. Bennett, hereby grant permission to the Wallace Library of the Rochester Institute of Technology to reproduce my thesis in whole or in part. Any reproduction must not be for commercial use or profit. Date: ~) J&/JOQ;2.. Signature of Author: _ Rochester Institute of Technology B. Thomas Golisano College of Computing and Information Sciences Master of Science in Information Technology Thesis Approval Form Student Name: Thomas R. Bennett Project Title: Economic Analysis of the Cost of Inconsistencies in the Implementation of ISON Network Layer Standards Thesis Committee Name Signature Date Prof. Rayno Niemi Chair Prof. Jim Leone Committee Member Mr. Michael Valcourt Committee Member TABLE OF CONTENTS Chapter Page TABLE OF CONTENTS i LIST OF FIGURES ii LIST OF TABLES iv ACKNOWLEDGEMENTS v ABSTRACT 1 I. INTRODUCTION 2 II. BACKGROUND 9 III. CASE STUDY ANALYSIS 35 A. PROCESS FOR SELECTION 35 B. TESTING AND ALAYISIS PROCEEDURE 36 C. CASE A 45 D. CASE B 50 E. CASE C 56 F. CASE D 62 G. CASE E 71 H. CASE F 75 I. CASE G 82 D. CASE H 86 IV. CASE STUDY ECONOMIC EVELUATION 94 V. SUMMERY OF IMPACT AND RECOMMENDATIONS 1 1 1 VI. REFERENCES 117 LIST OF FIGURES Number Page 1-1 Typical Analog Telecommunications Network 2 1-2 OSI Reference Model and ISDN Protocol Stacks 4 1-3 Primary Rate ISDN Channel Mapping - FAS 4 II-l ISDN Physical Layer Interface Points 10 II-2 Typical Multi-Vendor ISDN Configuration 11 II-3 Extended Super Frame Format - DS1 Signaling 12 II-4 B8ZS Line Coding- DS1 Signaling 13 II-5 The I Frame for the Data-Link Layer 15 II-6 The U Frame for the Data-Link Layer 16 II-7 The S Frame for the Data-Link Layer 17 II-8 Procedure for I Frame Acknowledgement Using RR Frames 18 II-9 General Message Format Layer 3 22 11-10 The Call Reference 23 11-11 Messages Passed via PSTN Signaling System 26 11-12 SS7 Protocol Stack 27 11-13 Message Flow for Call Establishment 28 11-14 ANSI and ITU-T Initial Address Message (IAM) Format 29 11-15 ANSI and ITU-T Address Complete Message (ACM) Format 30 11-16 ANSI and ITU-T Answer Message (ANM) Format 31 11-17 Message Flow for Call Tear Down 32 11-18 ANSI and ITU-T Release (REL) Message Format 33 11-19 ANSI and ITU-T Release Complete (RLC) Message Format 34 III-l The Setup Message 36 III-2 Typical Analyzer Schematic (non 5ESS) 38 III-3 Typical Analyzer Schematic (5ESS) 39 III-4A Typical Setup Message 40 III-4B Setup Message Header 41 III-4C Bearer Capability IE Decode 42 III-4D Channel ID IE Decode 43 III-4E Calling Party IE Decode 44 III-4F Called Party IE Decode 45 "A" III-5A Case Setup Message 47 "A" III-5B Case Release Complete Message 48 "A" III-5C Case decoded Release Complete Message 49 III-5D North American Numbering Plan 49 "A" III-5E Case Decoded Called Party IE 50 "B" III-6A Case Setup Message 52 "B" III-6B Case Call Proceeding Message 53 "B" III-6C Case Progress Message 53 "B" III-6D Case Disconnect Message 54 "B" III-6E Case Release Message 54 "B" III-6F Case Setup Message, Called Number I.E. Decode 55 n "B" III-6G Case Progress Message. Progress I.E. decode 56 "C" III-7A Case Setup Message 58 "C" III-7B Case Release Complete Message 59 "C" III-7C Case Decoded Release Complete Message 60 "C" III-7D Case Decoded Network Specific Facility I.D 61 "D" III-8A Case SS7 ISUP Release Message 63 "D" III-8B Case SS7 Initial Address Message 64 "D" III-8C Case Setup Message 66 "D" III-8D Case Decoded Calling Party IE 67 "E" III-9A Case Setup Message 73 "E" III-9B Case Call Proceeding Message 74 "E" III-9C Case Progress Message 74 "E" III-9D Case Disconnect Message 75 "F" 111-10 Case Intra Switch Connection Diagram 76 "F" III-10A Case User A Setup Message 78 "F" III-10B Case User A Call Proceeding Message 79 III-10C Case "F" User A Disconnect Message 79 "F" III-10D Case User A Release Message 79 III-10E Case "F" User A Release Complete Message 80 III-10F Case "F" User A Decoded Progress IE 81 "F" III-10G Case User A Decoded Progress IE (after software fix) 82 III-11A Case "G" SS7 ISUP Release Message 84 III-11B Case "G" SS7 ISUP Release Complete Message 84 III-11C Case "G" SS7 ISUP IAM Access Transport 85 "G" III-11D Case Setup Message Progress Message 86 III-11E Case "G" ISUP Access Transport (post fix) 86 III-12A Case "H" SS7 ISUP IAM (3.1 Khz) 88 "H" III-12B Case Setup Message (speech) 89 III-12C Case "H" Bearer Capability IE Decode 90 III-12D Case "H" Setup Message Progress IE Decode 91 "H" III-12E Case Layer 3 Setup Message with Progress I.E. Removed 92 III-12F Case "H" SS7 IAM Showing Speech Transfer Rate 92 m LIST OF TABLES Number Page 1-1 Signaling in an Analog Telecommunications Network 3 II-l Common SAPI and TEI Address's 14 II-2 Examples of U Frames 16 II-3 Examples of the S Frame 17 II-4 ISDN Call Control (Layer 3) Messages 21 II-5 Message Types / Values 24 II-6 Information Element Identifiers 25 III-l Valid Information Elements 37 III-2 Layer 3 Timers 69 "E" III-3 Case Summary of Events 72 "F" III-4 Case Summary of Events 77 IV-1 Layer 3 Trouble Reports - 1/1/01 through 12/31/01 95 IV-2 Case "A" Costs 97 IV-3 Case "B" Costs 98 IV-4 Case "C" Costs 99 IV-5 Case "D" Costs 100 IV-6 Case "E" Costs 101 IV-7 Case "F" Costs 102 IV-8 Case "G" Costs 103 IV-9 Case "H" Costs 104 IV-10 Group I Average Expenses 105 IV-11 Group II Average Expenses 106 IV-12 Group III Average Expenses 106 IV-13 Group IV Average Expenses 107 IV-14 Annual Expenses by Group 107 IV-15 Percentage ofTotal Annual group Expense by Type 109 IV-16 Percentage ofTotal Annual Expense by Group 109 IV ACKNOWLEDGMENTS I would like to thank Dr. Rayno Niemi for his support and the patience he has shown me through out this project. I would also like to thank professor Diane Bills for assisting in my re-admittance to the graduate school at RIT, and allowing me to continue with this thesis. There are several people at WorldCom who directly assisted me in preparing this Thesis. I would like to thank Shawn Haubrich, Jason Bauman, Tracey Knight and Matthew Ottey for their help in data captures and analysis. I would also like to acknowledge the management in WorldCom for providing flexibility with my work schedule so that I could continue the research for this thesis. Special thanks to Roland Lemus and Michelle Shuchman for providing me the opportunity to do what I truly enjoy, and derive a paycheck to boot. I, also want to thank my two sons', Justin and Travis for helping me recover from computer crashes, and giving me spiritual strength to continue with this project. And my daughter Ashley for her light heart and sense of humor which was sorely needed during the later stages when I remained glued to a PC for days at a time. Finally, I would like to thank my dear wife Sheree. She has remained by my side, through thick and thin for twenty-two plus years. She has endured the endless routine of night school, undergraduate and graduate studies, and put up with my antisocial behavior patterns during the past months as I neared completion of this thesis. Through all this she never lost faith in me, and her inspiration and strength became the driving force in me to finish this thesis. I was truly blessed the day that I met Sheree. ABSTRACT Case studies depicting ISDN network layer interoperability and standards nonconformance were evaluated, and categorized by type. In each case study the root cause of the interoperability problem was identified, and validated with reference to the applicable ISDN standard. Corrective measures were proposed, and where implemented, the results of the correction were documented.
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