Data communication and networking - introduction

Data communication and networking - introduction

• 1.
  Chapter 1 Introduction 1.1
• 2.
  1-1 DATA COMMUNICATIONS Theterm telecommunication means communication at a distance. The word data refers to information presented in whatever form is agreed upon by the parties creating and using the data. Data communications are the exchange of data between two devices via some form of transmission medium such as a wire cable. Delivery, Accuracy, Timeliness,Jitter Topics discussed in this section: Components Data Representation Data Flow 1.2
• 3.
  Figure 1.1 Fivecomponents of data communication 1.3
• 4.
  Data Representation Text Numbers Image Vidio Audio 1.4
• 5.
  Figure 1.2 Dataflow (simplex, half-duplex, and full-duplex) 1.5
• 6.
  1-2 NETWORKS A networkis a set of devices (often referred to as nodes) connected by communication links. A node can be a computer, printer, or any other device capable of sending and/or receiving data generated by other nodes on the network. Topics discussed in this section: Distributed Processing Network Criteria ::Performance,reliability,Security Physical Structures Network Models Categories of Networks Interconnection of Networks: Internetwork 1.6
• 7.
  Figure 1.3 Typesof connections: point-to-point and multipoint 1.7
• 8.
  Figure 1.4 Categoriesof topology 1.8
• 9.
  Figure 1.5 Afully connected mesh topology (five devices) 1.9
• 10.
  Figure 1.6 Astar topology connecting four stations 1.10
• 11.
  Figure 1.7 Abus topology connecting three stations 1.11
• 12.
  Figure 1.8 Aring topology connecting six stations 1.12
• 13.
  Figure 1.9 Ahybrid topology: a star backbone with three bus networks 1.13
• 14.
  Figure 1.10 Anisolated LAN connecting 12 computers to a hub in a closet 1.14
• 15.
  Figure 1.11 WANs:a switched WAN and a point-to-point WAN 1.15
• 16.
  Figure 1.12 Aheterogeneous network made of four WANs and two LANs 1.16
• 17.
  1-3 THE INTERNET TheInternet has revolutionized many aspects of our daily lives. It has affected the way we do business as well as the way we spend our leisure time. The Internet is a communication system that has brought a wealth of information to our fingertips and organized it for our use. Topics discussed in this section: A Brief History The Internet Today (ISPs) 1.17
• 18.
  Figure 1.13 Hierarchicalorganization of the Internet 1.18
• 19.
  1-4 PROTOCOLS ANDSTANDARDS In this section, we define two widely used terms: protocols and standards. First, we define protocol, which is synonymous with rule. Then we discuss standards, which are agreed-upon rules. Topics discussed in this section: Protocols :: Syntax,Semantics,Timing Standards Standards Organizations Internet Standards 1.19