Course Instructor : Sehrish Rafiq

Department Of Computer Science

University Of Peshawar

Data Communications & NetworkingLecture-01

Readings recommended

Data Communications & Networking 3rd Edition by Behrouz A.Forouzon

Data & Computer Communications 6th edition by william stallings

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

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.

Why study data communication?

EntertainmentBusinessEducation & researchSpace missionsPC revolutionTelecommunications

Fundamental characteristics of a data communication system

The effectiveness of a data communication system depends on three fundamental characteristics:

Delivery Accuracy Timeliness

Components of a Data communication system

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.

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

HAVE A NICE DAY!!!