Computer Networks and Devices - Revision Notes
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.