Computer network
- 1. Table Of Contents • COMPUTER NETWORK • Advantages • Disadvantages • Node and Data Transfer Rate • Client/Server Model • File Server And Web Server • LAN, WAN & MAN • Internet • Who owns the Internet? • Internet Backbone and ISP • Internet Connections • Packet Switching • TCP and IP • Any Queries? • Project Work- Computer
- 2. COMPUTER NETWORK • A collection of computing devices that are connected in various ways in order to communicate and share resources. • Usually, the connections between computers in a network are made using physical wires or cables. However, some connections are wireless, using radio waves or infrared signals.
- 3. Advantages • Sharing devices such as printers saves money. • Site (software) licenses are likely to be cheaper than buying several standalone licenses. • Files can easily be shared between users. • Network users can communicate by email and instant messenger. • Security is good - users cannot see other users' files unlike on stand-alone machines. • Data is easy to backup as all the data is stored on the file server.
- 4. Disadvantages • Purchasing the network cabling and file servers can be expensive. • Managing a large network is complicated, requires training and a network manager usually needs to be employed. • If the file server breaks down the files on the file server become inaccessible. Email might still work if it is on a separate server. The computers can still be used but are isolated. • Viruses can spread to other computers throughout a computer network. • There is a danger of hacking, particularly with wide area networks. Security procedures are needed to prevent such abuse.
- 5. Node and Data Transfer Rate • The generic term node or host refers to any device on a network • The speed with which data is moved from one place on a network to another called data transfer rate. • Data transfer rate is a key issue in computer networks
- 6. Client/Server Model • Computer networks have opened up an entire frontier in the world of computing called the client/server model.
- 7. File Server And Web Server File Server • A computer that stores and manages files for multiple users on a network. Web Server • A computer dedicated to responding to requests (from the browser client) for web pages.
- 8. LAN, WAN & MAN • LAN(Local Area Network): A network that connects a relatively small number of machines in a relatively close geographical area. • WAN(Wide Area Network): A network that connects two or more local-area networks over a potentially large geographic distance • MAN(Metropolitan Area Network): The communication infrastructures that have been developed in and around large cities
- 9. Internet • The Internet is the global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link billions of devices worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. • The Internet carries an extensive range of information resources and services, such as mobile apps including social media apps, the inter-linked hypertext documents and applications of the World Wide Web (WWW), e- mail, multiplayer online games, telephony, and peer-to-peer networks for file sharing.
- 10. Who owns the Internet? • Well, nobody does. No single person or company owns the Internet or even controls it entirely. As a wide-area network, it is made up of many smaller networks. These smaller networks are often owned and managed by a person or organization. The Internet, then, is really defined by how connections can be made between these networks.
- 11. Internet Backbone and ISP Internet Backbone • A set of high-speed networks that carry Internet traffic. • These networks are provided by companies such as AT&T, GTE, and IBM. ISP(Internet Service Provider) • A company that provides other companies or individuals with access to the Internet
- 12. Internet Connections • There are various technologies available that you can use to connect a home computer to the Internet. – A phone modem converts computer data into an analog audio signal for transfer over a telephone line, and then a modem at the destination converts it back again into data. – A digital subscriber line(DSL) uses regular copper phone lines to transfer digital data to and from the phone company’s central office. – A cable modem uses the same line that your cable TV signals come in on to transfer the data back and forth.
- 13. Packet Switching • To improve the efficiency of transferring information over a shared communication line, messages are divided into fixed-sized, numbered packets. • Network devices called routers are used to direct packets between networks.
- 14. TCP and IP TCP • TCP stands for Transmission Control Protocol. • TCP software breaks messages into packets, hands them off to the IP software for delivery, and then orders and reassembles the packets at their destination. IP • IP stands for Internet Protocol. • IP software deals with the routing of packets through the maze of interconnected networks to their final destination.
- 15. Any Queries?
- 16. Project Work- Computer Submitted By: • Rahul Das • 8”C” • 6 • Yellow • V.S. Niketan • ……………………………… Submitted To: • Jeevan Sir • V.S. Niketan • ………………………………….