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.
  • hub is a hardware device used to connect several computers together. Hubs can be either active hubs or passive hubs.
  • switch is a device that is used to segment networks into different sub-networks called subnets or LAN segments.
  • bridge is a device that links two networks together.
  • router is a device that works like a bridge but can handle different protocols.
  • 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.