The document is a lecture overview on data communications and networking, detailing its significance, components, and fundamental characteristics. It defines data communication as the exchange of binary data between devices and outlines the structure of communication systems, including networks and distributed processing. Key aspects discussed include the importance of data communication across various fields and the characteristics of effective communication systems: delivery, accuracy, and timeliness.

1. Course Instructor : Sehrish Rafiq
Department Of Computer Science
University Of Peshawar
Data Communications & Networking
Lecture-01

2. Readings recommended
 Data Communications & Networking 3rd Edition by Behrouz
A.Forouzon
 Data & Computer Communications 6th edition by william stallings

3. Lecture Overview
 What is Data communication?
 Importance of Data communication
 Fundamental characteristics of a data communication system
 Components of a data Communication system
 Networks & distributed processing

4. What is Data Communication?
 The word data refers to facts,concepts and instructions presented in
whatever form is agreed upon by the parties creating and using the
data.
 In context of computer information systems data are represented by
binary information units(or bits) produced and consumed in the form of
0’s and 1’s.
 Data Communication is the exchange of data (in the form of 0’s and 1’s)
between devices via some form of transmission medium(such as a wire
cable).
 Local and remote data communication
 For data communication to occur the communicating devices must be a
part of a communication system made up of a combination of hardware
& software.

5. Why study data communication?
 Entertainment
 Business
 Education & research
 Space missions
 PC revolution
 Telecommunications

6. Fundamental characteristics of a data
communication system
 The effectiveness of a data communication system depends on
three fundamental characteristics:
 Delivery
 Accuracy
 Timeliness

7. Components of a Data communication system

8. Networks
 A network is a set of devices(often referred to as nodes)
connected by media 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.
 The links connecting the devices are often called communication
channels.

9. Distributed Processing
 In distributed processing a task is divided among multiple
computers.
 Instead of a single large machine being responsible for all
aspects of a process,each separate computer handles a subset.
 Advantages of distributed processing:
 Security/Encapsulation e.g. ATM
 Distributed databases e.g. World Wide Web
 Faster Problem solving e.g. Encryption Codes
 Security through redundancy e.g. space programs
 Collaborative processing e.g. Games in a multi-user environment

10. HAVE A NICE DAY!!!