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Performance Analysis of Token Bus Protocol with Maintenance Functions Joon-Nyun Kim Iowa State University

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Performance Analysis of Token Bus Protocol with Maintenance Functions Joon-Nyun Kim Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1987 Performance analysis of token bus protocol with maintenance functions Joon-Nyun Kim Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Electrical and Electronics Commons, and the Transportation Commons Recommended Citation Kim, Joon-Nyun, "Performance analysis of token bus protocol with maintenance functions " (1987). Retrospective Theses and Dissertations. 8663. https://lib.dr.iastate.edu/rtd/8663 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS The most advanced technology has been used to photo­ graph and reproduce this manuscript from the microfilm master. UMI films the original text directly from the copy submitted. Thus, some dissertation copies are in typewriter face, while others may be from a computer printer. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyrighted material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are re­ produced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each oversize page is available as one exposure on a standard 35 mm slide or as a 17" x 23" black and white photographic print for an additional charge. Photographs included in the original manuscript have been reproduced xerographically in this copy. 35 mm slides or 6" X 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. •UMIAccessing the World's Information since 1938 300 North Zeeb Road, Ann Arbor Ml 48106-1346 USA Order Number 8805093 Performance analysis of token bus protocol with maintenance functions Kim, Joon-Nyun, Ph.D. Iowa State University, 1987 UMI 300N.ZeebRd. Ann Arbor, MI 48106 PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . 1. Glossy photographs or pages 2. Colored illustrations, paper or print 3. Photographs with dark background 4. Illustrations are poor copy 5. Pages with black marks, not original copy 6. 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Other UMI Performance analysis of token bus protocol with maintenance functions by Joon-Nyun Kim A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Department: Electrical Engineering and Computer Engineering Major: Computer Engineering Approved; Signature was redacted for privacy. in ChgA^e of Major Work Signature was redacted for privacy. pbr Department Signature was redacted for privacy. For the Graduate College Iowa State University Ames, Iowa 1987 i i TABLE OF CONTENTS PAGE CHAPTER 1. INTRODUCTION 1 Local Area Network Overview 1 Performance Issue in Local Area Networks 4 Problem Definitions and Research Objectives 6 Outline of Dissertation 10 CHAPTER 2. TOKEN BUS PROTOCOL DESCRIPTION 11 Basic Operation of the Token Bus Protocol 11 Frame Formats of Token Bus Protocol 13 Preamble ...... 14 Start delimiter 14 Frame control 15 Address field 15 Data unit 15 Frame check sequence 16 End delimiter 16 MAC Layer Operation 16 MAC layer functions 17 Basic operations 17 Right to transmit 18 Token passing 18 MAC Layer Internal Structure 19 Interface machine 19 Access control machine ..... 21 Receive machine 21 Transmit machine 21 ACM Finite State Machine Description 22 Offline 22 Idle 22 Demand_in ,24 Demand_delay 24 Claim_token 25 Use_token 25 Await_IFM_response 25 Check_access_class 26 Pass_token 26 Check_token_pass 27 Await_response 27 CHAPTER 3. TOKEN BUS PROTOCOL MAINTENANCE FUNCTIONS ... 28 Ring Initialization 28 Station Addition 29 Station Deletion 31 Token Recovery 31 Receiver Fault Recovery 32 Transmitter Fault Recovery 33 Overhead Analysis of Maintenance Functions 33 i i i Ring initialization ' 33 Station addition 34 Station deletion 34 Token recovery 34 Receiver fault recovery 35 Transmitter fault recovery 35 CHAPTER 4. PERFORMANCE ANALYSIS OF TOKEN BUS PROTOCOL . 36 Token Bus Protocol without Maintenance Functions ... 38 Average cycle time 38 Message delay 40 Token Bus Protocol with Maintenance Functions .... 45 CHAPTER 5. REAL SYSTEM APPLICATION 48 Effect of Maintenance Functions 48 Scenario Study 62 CHAPTER 6. CONCLUSIONS AND FUTURE WORK , ... 66 Conclusions 66 Future Work 69 Simulation modeling 69 Reliability of maintenance functions 69 Statistical performance analysis 70 BIBLIOGRAPHY 71 ACKNOWLEDGEMENT 75 APPENDIX A. MAC CONTROL FRAME FORMATS 76 APPENDIX B. BENCHMARK INPUT DATA 78 iv LIST OF TABLES PAGE TABLE 1., MAC control frame transmission time 46 TABLE 2. Maintenance delays 47 TABLE 3. Recalculated maintenance delay 49 TABLE 4. Ring initialization maintenance delay 56 TABLE 5. Station addition maintenance delay 57 TABLE 6. Station deletion maintenance delay 58 TABLE 7, Token recovery maintenance delay . 59 TABLE 8. Receiver fault recovery maintenance delay ... 60 TABLE 9. Transmitter fault recovery maintenance delay 61 TABLE 10. The worst case maintenance delay 65 V LIST OF FIGURES PAGE FIGURE 1. Bus, ring, and star configurations 2 FIGURE 2. Layer structure of LAN model [31] 5 FIGURE 3. Logical ring on physical bus 12 FIGURE 4. Frame format for token bus protocol 14 FIGURE 5. MAC layer functional partitioning 20 FIGURE 6. ACM finite state machine transition diagram 23 FIGURE 7. Queueing model for token bus logical ring . 37 FIGURE 8, Division of delays for a typical message ... 41 FIGURE 9. A cycle for a polling network 42 FIGURE 10. Ring initialization maintenance delay .... 50 FIGURE 11. Station addition maintenance delay 51 FIGURE 12. Station deletion maintenance delay ...... 52 FIGURE 13. Token recovery maintenance delay 53 FIGURE 14. Receiver fault recovery maintenance delay . 54 FIGURE 15. Transmitter fault recovery maintenance delay 55 FIGURE 16, The worst case maintenance delay 64 1 CHAPTER 1. INTRODUCTION Local Area Network Overview During the past decade, local area networks have become one of the most publicized and controversial topics in the data communications field, that have produced numerous publications [1-8] dealing with various aspects of local area networks. The publicity surrounding local area networks stems from what they are purported to do for an organization; the controversy comes from how they are to do it. Due to the versatility, however, local area networks will play a prominent role in computer communications and distributed processing in the 1980s. Basically, a local area network is an interconnected set of computers which is geographically limited from a distance of several thousand feet to a few miles, and is structured around a high-speed, low-noise connecting link or channel that typically supports data rate of 500 Kbps to 50 Mbps. As illustrated in Figure 1, there are three basic topologies in local area networks: the bus, the ring, and the star. The bus topology is appropriate for transmission medium such as coaxial cable which allows high-impedance taps. In principle, these taps do not affect the medium and 2 a large number of stations can be connected. This topology is particularly suitable for the random accessing techniques. ? ? ? ? Ô Ô Ô .0 FIGURE 1. Bus, ring, and star configurations The ring topology is a sequence of point-to-point links with flow of data in one direction around the ring. In this case, there is a delay due to data processing at each station and for reliability reason, there are provisions to bypass stations if they become inoperative. In both cases of bus and ring, the control of traffic is distributed among stations. 3 In the star topology, the control is concentrated in a central hub where all the data are collected and routed to appropriate stations through high-speed channels. In contrast to this, data are packetized and all packets traverse the same channel in most bus and ring systems, and the path of a given packet carries it past all stations on the network. Thus, although addressing information is still required, routing is unnecessary. The main motivation for local area networking is resource sharing. Resources include not only devices such as computer and printer, but also data files which are costly to duplicate and expensive to maintain. It is often expedient to maintain central files or data banks that are shared by devices at work stations throughout a local area network. In addition to the primary justification for local area networks, there are a number of secondary effects. For example, the distributed resources of a local network provide redundancy for many devices and thus backup in the event of failures. Also, many local area networks provide speed and code conversion that enables equipment from different manufacturers to be connected easily without expensive special purpose interfaces. 4 Performance Issue in Local Area Networks As the interest grows in local area networks, the performance analysis of these networks has become one of the main topics in local network study [9-29].
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