Client Server Computing Architecture, Applications and Distribution System Devendra Kumar GLOBAL VISION PUBLISHING HOUSE 20, Ansari Road, Daryaganj, New Delhi-110002 (INDIA)
Contents Acknowledgement (vii) Preface (ix) Chapter 1. Introduction to Client Server Computing 1 1.1. Introduction 1 1.2. Overview of Client Server Computing 2 1.2.1. Evolution of Client-Server Computing 3 1.2.2. Configurations in Client-Server Computing 4 1.2.3. Butler Pyramid Model of Client-Server Computing 5 1.3. Design Consideration of Client Server 6 1.3.1. Fat vs Thin Client 6 1.3.2. Stateful vs Stateless 6 1.3.3. Authentication 7 1.3.4. Fault Tolerance 7 1.4. Client Server Computing Model 7 1.4.1. Benefits of Client Server Model 9 1.5. Database Concept 10 1.5.1. Client Server Database 10 1.5.2. Client Server Database Computing 10 1.5.3. Client Server Database Computing vs Mainframe and PC/File Server Computing 11 1.5.4. Three-Schema Architecture 11 1.5.5. Client Server Database Architecture 12 1.5.6. Types of Client Server Database Architecture 14 1.5.7. Advantages of Client Server Database 16 1.5.8. Disadvantages of Client Server Database 17
(xii) Client Server Computing 1.6. Client Server Architecture 18 1.6.1. Types of Client Server Architectures 18 1.6.2. Characteristics of Client Server Architecture 24 1.7. Single System Image 24 1.7.1. Types of Single System Image 24 1.7.2. Single System Image Services and Benefits 26 1.8. Mainframe Centric Client Server Computing 27 1.8.1. Advantages of Mainframe-Centric Client-Server Computing 28 1.9. Downsizing and Client-Server Computing 29 1.10. Preserving Your Mainframe Applications Investment Through Porting 30 1.11. Client Server Development Tools 31 1.12. Advantages and Disadvantages of Client Server Computing 32 1.12.1. Advantages of Client-Server Computing 32 1.12.2. Disadvantages of Client-Server Computing 34 1.13. Summary 35 1.14. Study Questions 36 Chapter 2. Components of Client Server Application: The Client 37 2.1. Introduction 37 2.2. The Client 38 2.2.1. The Clients'Role 38 2.2.2. Client Services 39 2.3. Dynamic Data Exchange (DDE) 41 2.3.1. Dyamic Data Exchange Functions 43 2.4. Object Linking and Embedding (OLE) 43 2.4.1. History of OLE 45 2.5. Component Object Model (COM) 46 2.6. Distributed Component Object Model (DCOM) 47 2.7. Object Request Broker (ORB) 48 2.7.1. Object Request Broker Services 49 2.8. Common Object Request Broker Architecture (CORBA) 50 2.8.1 Benefits ofcorba 52 2.8.2. Drawbacks of CORBA 53 2.9. Summary 54 2.10. Study Questions 55
Contents (xiii) Chapter 3. Components of Client Server Application: The Server 56 3.1. Introduction 56 3.2. The Server 57 3.2.1. The Server's Role 57 3.2.2. Details Server Functionality or Services 58 3.3. Network Operating Systems (NOS) 59 3.3.1. Functions of NOSs 60 3.3.2. Types of Network Operating System (NOS) 60 3.3.3. Features of Network Operating System 61 3.3.4. Network Administrator 61 3.3.5. Banyan VINES 62 3.4. Available Platform 62 3.4.1. Workstation in LAN Configuration 62 3.4.2. LAN-to-LAN/WAN Configuration 63 3.4.3. LAN-to-Host Configuration 63 3.4.3. OLTP on a LAN 63 3.4.4. OLTP with UNIX 63 3.5. Server Operating System (SOS) 63 3.5.1. Netware 64 3.5.2. OS/2 65 3.5.3. Windows NT 65 3.5.4. Multiple Virtual Storage (MVS) 65 3.5.5. Virtual Memory System (VMS) 65 3.5.6. OpenVMS 66 3.5.7. UNIX 66 3.6. Distributed Computing Environment (DCE) 68 3.6.1. Distributed Computing Environment Services 68 3.7. System Application Architecture (SAA) 69 3.7.1. SAA Defined Three Layers of Service 69 3.8. Client Server Security 69 3.9. Summary 70 3.10. Study Questions 71 Chapter 4. Client Server Network: Connectivity 72 4.1. Introduction 73 4.2. Peer-to-Peer Network 74
(xiv) Client Server Computing 4.2.1. Advantages of Peer-to-Peer Network 74 4.2.2. Disadvantages of Peer-to-Peer Network 74 4.3. Client Server Network 75 4.3.1. Advantages of a Client Server Network 75 4.3.2. Disadvantages of a Client Server Network 75 4.4. OSI Model 75 4.5. Communication Interface Technology 77 4.6. LAN Cabling 78 4.6.1. Shielded Twisted Pair (STP) 78 4.6.2. Unshielded Twisted Pair (UTP) 78 4.6.3. Coaxial Cable 79 4.6.4. Fiber Optic Cable 80 4.7. Fiber Distributed Data Interface (FDDI) 80 4.7.1. FDDI Frame Format 82 4.7.2. FDDI Benefits 83 4.8. Ethernet 83 4.8.1. Ethernet Characteristics 83 4.8.2. Ethernet Classes 83 4.9. Token Ring 84 4.9.1. Token Ring Frame 85 4.9.2. Token Ring Operation 86 4.9.3 Token Ring IEEE 802.5 86 4.9.5. Advantages of Token 87 4.9.6. Disadvantages of Token 87 4.10. Copper Distributed Data Interface (CDDI) 87 4.11. Hypertext Transfer Protocol (HTTP) 87 4.12. Transport Control Protocol/Internet Protocol (TCP/IP) 87 4.12.1. TCP/IP Model 88 4.13. File Transfer Protocol (FTP) 89 4.13.1. Advantages of FTP 90 4.13.2. Disadvantages of FTP 90 4.14. Simple Mail Transfer Protocol (SMTP) 90 4.14.1. Features of SMTP 91 4.14.2. Applications of SMTP 91 4.14.3. Advantages of SMTP 92
Contents (XV). 4.14.4. Disadvantages of SMTP 92 4.15. Simple Network Management ProtocoL (SNMP) 92 4.15.1. SNMP Feature 92 4.15.2. Advantages of Using SNMP 94 4.16. Telnet 95 4.17. Hubs 95 4.17.1. Types of Hub 96 4.17.2. Advantages of Hub 97 4.17.3. Disadvantages of Hub 97 4.18. Routers 97 4.18.1. Advantages of Router 98 4.18.2. Disadvantages of Router 98 4.19. Bridge 98 4.19.1 Three Basic Types of Bridges 99 4.19.2. Advantages of Bridge 99 4.19.2. Disadvantages of Bridge 99 4.20. Network File System (NFS) 99 4.20.1. NFS Offers a Number of Advantages 100 4.21. Asynchronous Transfer Mode (ATM) 100 4.22. Network Interface Card (NIC) 101 4.23. Local Area Network (LAN) 103 4.24. Metropolitan Area Network (MAN) 103 4.25. Wide Area Network (WAN) 104 4.26. Inter-Process Communication (IPC) 105 4.26.1. Types of IPC 106 4.26.2. Features of IPC 106 4.26.3. IPC Services 107 4.27. WAN Technologies 107 4.28. Switched Multimegabit Data Service (SMDS) 107 4.28.1. SMDS Network Connections 108 4.29. Integrated Services Digital Network (ISDN) 109 4.29.1. Channels of ISDN 109 4.29.2. Services of ISDN 109 4.29.3. Advantages of ISDN 109 4.29.4. Disadvantages of ISDN 110
Client Server Computing 4.30. Frame Relay (FR) 110 4.30.1. Frame Relay Structure 111 4.30.2. Advantages of Frame Relay 112 4.31. Network Topology 112 4.31.1 Bus Topology 112 4.31.2 Star Topology 113 4.31.3 Tree Topology 114 4.31.4. Ring Topology 115 4.30.5. Mesh Topology 116 4.31.6. Hybrid Topology 117 4.32. Network Management 117 4.32.1 Fault Management 119 4.32.2. Performance Management 120 4.32.3. Configuration Management 121 4.32.4. Security Management 122 4.31.5. Accounting Management 124 4.33. Summary 124 4.34. Study Questions 125 Chapter 5. Client Server System Development Software 127 5.1. Introduction 127 5.2. Business Process Re-engineering (BPR) 128 5.3. Factor Driving Demand for Application Software Development 129 5.3.1. Pressure to Build Competitive Advantage by Delivering Systems Faster 129 5.3.2. Rising Technology Staff Costs 129 5.3.3. Need for Platform Migration and Re-engineering of Existing Systems 129 5.3.4 Need to Improve Technology Professionals' Productivity 130 5.3.5. Need for a Common Interface Across Platforms 130 5.3.6. Increase in Applications Development by Users 131 5.4. Client Server Systems Development Methodology 131 5.4.1. System Planning 132 5.4.2. Project Initiation 133 5.4.3. Architecture Definition 133 5.4.4. Analysis 133 5.4.5. Design 134 5.4.6. Development 134
Contents (xvii) 5.4.7. Facilities Engineering 134 5.4.8. Implementation 134 5.4.9. Post Implementation Support 135 5.5. Project Management 135 5.5.1. Plan the Project 135 5.5.2. Manage and Control Project Execution 136 5.5.3. Complete the Project 136 5.6. Architecture Definition 136 5.7. System Development Environment (SDE) 137 5.8. Summary 139 5.9. Study Questions 139 Chapter 6. Client Server System Development Hardware 140 6.1. Introduction 140 6.2. Hardware/Network Acquisition 141 6.3. PC-Level Processing Units 142 6.4. Macintosh 142 6.4.1. Advantages 142 6.4.2. Disadvantages 143 6.5. Notebook 143 6.6. Pen 143 6.7. UNIX Workstation 144 6.8. X-Terminal 144 6.9. X-Server 145 6.10. Server Hardware 145 6.11. Summary 145 6.12. Study Questions 146 Chapter 7. Data Storage 147 7.1. Introduction 147 7.2. Magnetic Tape 150 7.2.1. Audio Recording 151 7.2.2. Video Recording 152 7.3. Magnetic Disk 152 7.3.1. Hard Disk 153 7.3.2. Floppy Disk 154
(xviii) Client Server Computing 7.3.3. Removable Cartridge 156 7.4. Optical Disk 156 7.4.1. Read-Only Optical Disks 156 7.4.2. Write Once and Read Many (WORM) 157 7.4.3. Erasable 157 7.5. Mirroring Disk 157 7.6. Fault Tolerant 158 7.7. Redundant Array of Independent Disk (RAID) 158 7.7.1. RAID Levels 159 7.7.2. Goals of Raid Technology 159 7.8. Network Interface Card (NIC) 160 7.9. Network Protection Device 160 7.10. Power Protection Devices 161 7.10.1. Uninterruptible Power Supply (UPS) 161 7.10.2. Surge Protector 162 7.11. Summary 162 7.12. Study Questions 163 Chapter 8. Client Server Systems Development Service and Support 164 8.1. Introduction 164 Benefits of Client Server Applications 165 8.2. System Administrator 165 8.2.1. Database Administrator (DBA) 166 8.3. Availability 166 8.4. Reliability 167 8.5. Serviceability 167 8.5.1. Asset/License Management 167 8.5.2. Change Management 168 8.5.3. Problem Management 168 8.6. Software Distribution 169 8.6.1. Software Distribution Objects 169 8.7. Network Management 170 8.8. Help Desk 170 8.8.1. Help Desk Team 171 8.9. Remote Systems Management 171 8.9.1. RSM Background Service 171
Contents (xix) 8.9.2. RSM Benefits 171 8.9.3. RSM Security 171 8.10. LAN and Network Management Issues 172 8.11. Summary 172 8.12. Study Questions 173 Chapter 9. Client Server System Development: Training 174 9.1. Introduction 175 9.2. Training 175 9.3. Graphical User Interface (GUI) 175 9.4. Training Advantages of GUI Applications 175 9.4.1. Reduced Training Cost 176 9.4.2. Training the Technical Staff 176 9.5. System Administrator Training 177 9.5.1. LAN Administrator 177 9.5.2. WAN Issue 178 9.5.3. Operating System Issue 178 9.5.4. PC/Workstation Issues 179 9.5.5. Application Issues 179 9.6. Database Administrator Training 179 9.7. End User Training 179 9.7.1. Workstation Operations 179 9.7.2. Application and New Technologies 180 9.8. Training Delivery Technology 180 9.9. Future of Client Server Computing 181 9.10. Enabling Technology 181 9.11. Expert System 182 9.11.1. Expert System Components 182 9.11.2. Expert System Architecture 183 9.11.3. Types of Expert System 183 9.11.4. Expert System Advantages 184 9.11.5. Expert System Disadvantages 185 9.12. Geographic Information Systems (GIS) 186 9.12.1. Advantages of Geographic Information System 187 9.12.2. Disadvantages of Geographic Information System 187
Client Server Computing 9.13. Point-of-service (POS) 9.14. Imaging 9.15. Electronic Document Management Multimedia 9.16. Full-text Retrieval 9.17. Electronic Data Interchange (EDI) 9.17.1. Advantages of EDI 9.17.2. Disadvantages of EDI 9.18. Summary 9.19. Study Questions Previous Years Question Paper 188 189 190 190 191 192 192 193 193 195 Bibliography 197 Index 199