2.0 INTRODUCTION AND 2.1 OBJECTIVES

2.0 INTRODUCTION

A computer network is the infrastructure that allows two or more computers (called hosts) to communicate with each other. The network achieves this through two ways:

(i) by providing a set of rules for communication, called protocols, which should be observed by all participating hosts 

(ii) through communication devices which are the parts of a computer of network. In this unit, we shall learn about various types of network devices like gateway, bridges routers, hubs, switches, gateway and routers.

This unit shall also describe about different types of communication channels (media) and their advantages, disadvantages and application.

2.1 OBJECTIVES

After going through this unit, you should be able to: 

  • · understand the basics of communication devices;
  • · understand the basics of NIC, hub, repeater, bridges;
  • · understand usage of a router;
  • · understand the functionality of a switch;
  • · understanding different types of cabling like twister pair of cables, optical fibers, coaxial etc.; and
  • · understanding wireless media of communication.

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