McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Data Comm. & Networks Instructor: Ibrahim Tariq

My Introduction Engr. Ibrahim Tariq MS (Computer Engineering) from LUMS Area of Specialization: Wireless Networks BS (Telecommunication Engineering) from NU- FAST 1.2

Web group CS4592 at google group This webgroup will serve as a communication medium between you and me besides the lecture timing. Do visit the course yahoo group regularly 1.3

Reading Text book:  Data Communications and Networking, 4/e B.A. Forouzan, McGraw-Hill, 2003, ISBN Reference books:  Computer Networking, a top-down approach featuring the Internet(3 rd edition), J.K.Kurose, K.W.Ross, Addison-Wesley, 2005, ISBN  Computer Networks, A Systems Approach L. Peterson & Davie

Course Objective The course is designed to introduce you to the world of computer networks, so that you could know the science being used in running this network Use this knowledge in your professional field The course covers concepts and useful tools for design and performance analysis of data communication networks 1.5

Grading Policy Assignments/Quizzes : 24% Attendance : 12% Mid term : 24% Final Exam/project : 40% Grading Policy is Tentative 1.6

Lecture 1 Introduction

DATA COMMUNICATIONS The term 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. Components Data Representation Data Flow Topics discussed in this section:

1.9 Five components of data communication

1.10 Data flow (simplex, half-duplex, and full-duplex)

NETWORKS A network is 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. Distributed Processing Network Criteria Physical Structures Network Models Categories of Networks Interconnection of Networks: Internetwork Topics discussed in this section:

1.12 Types of connections: point-to-point and multipoint

1.13 Categories of topology

1.14 A fully connected mesh topology (five devices)

1.15 A star topology connecting four stations

1.16 A bus topology connecting three stations

1.17 A ring topology connecting six stations

1.18 A hybrid topology: a star backbone with three bus networks

Categories of Network Generally there are three categories of network 1. Local Area network (LAN) 2. Metropolitan Area Network (MAN) 3. Wide Area Network (WAN) Category into which a network falls is determined by its size 1.19

Categories of Network(2) Local Area Network (LAN) A local area network (LAN) is usually privately owned and links the devices in a single office, building, or campus Wide Area Network (WAN) A wide area network (WAN) provides long-distance transmission of data over large geographic area that may comprise a country, continent or world wide. Metropolitan Area Network (MAN) A metropolitan area network MAN )is a network with a size between a LAN and a WAN. Usually it is spreaded over a city or a part of a city 1.20

1.21 An isolated LAN connecting 12 computers to a hub in a closet

1.22 WANs: a switched WAN and a point-to-point WAN

THE INTERNET The Internet 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. A Brief History The Internet Today (ISPs) Topics discussed in this section:

1.24 Hierarchical organization of the Internet

1.25