Computer Networks and Devices

CBSE Class 12 Computer Science (Python)

Computer Networks and Devices
Revision Notes

Start here in points.
A network is a collection of interlinked computers by means of a communication system.
The networks facilitate resource sharing, increased reliability, reduced costs, and increased and fast communication.
On the basis of geographical spread, networks can be classified into LAN (Local Area Netowrk), and WAN (Wide Area Network).
Small computer networks that are confined to a localised area e.g., an office, a building etc., are called LANs.
A WAN is a group of computers that are separated by large distance and tied together. It can even be a group of LANs that are spread across several locations and connected together to look like a big LAN.
On the basis of component roles, networks can be classified into: a peer-to-peer network and a client-server network.
A Client computer (or a client) is a computer or other device on the other device on the network that requests and utilizes network resources.
A Server is a computer on network, dedicated to processing client requests.
In a peer-to-peer network, all computers are equal; each can double up as a client as well as a non-dedicated server.
A client/server network has computer(s) designated as server(s) and these are dedicated servers. Clients do own job and the servers serve the requests of the clients.
A hub is a hardware device used to connect several computers together. Hubs can be either active hubs or passive hubs.
A switch is a device that is used to segment networks into different sub-networks called subnets or LAN segments.
A bridge is a device that links two networks together.
A router is a device that works like a bridge but can handle different protocols.
A gateway is a device that connects dissimilar networks.
An access point (AP), also called wireless access point (WAP), is a hardware device that establishes connection(s) of computing devices on wireless LAN with a fixed wire network.
The cloud is a generic term for the Internet.
IOT is a phenomenon that connects the smart devices to the Internet over wireless connections.
IOT technology uses other technologies like RFID, sensors, smart technologies like controllers and specialized software.

Computer Networks and Devices - Revision Notes