Introduction to internet

introduction to internet. Computer network.

1. Introduction To Internet 1

2. Concept of network A network is any interconnected group of people or things capable of sharing meaningful information with one another. In a technology context, network is usually short for "computer network" or "data network" and implies that computers are the things sharing the meaningful information. 2

3. What Is Internet and Web? The internet is a globally connected network system facilitating worldwide communication and access to data resources through a vast collection of private, public, business, academic and government networks. It is governed by agencies like the Internet Assigned Numbers Authority (IANA) that establish universal protocols. Web is the part of the Internet that can be looked at with a special program (called a browser) and that is made up of many documents which are linked together. 3

4. Uses of computer network Computer networks can be used in many ways to make our life easy. For example – Information Sharing Hardware Resource Sharing Software Resource Sharing Information Preservation Exchanging Message Remote Using Database Management Office Automation Security 4

5. Uses of computer network Source of information Education medium Entertainment Communication Sharing capabilities 5

6. Types Of Internet Services Dial Up Internet Cable Internet 6

7. Types Of Internet Services Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network to establish a connection to an Internet service provider by dialing a telephone number on a conventional telephone line. It  uses a 56k modem and a phone line to create a connection. A modem at the ISP's side then takes the analog signal it receives and converts it back to a digital signal. Converting the signal more than once causes degradation and can cause reduced speeds. 7

8. Types Of Internet Services DSL stands for Digital subscriber line. Digital subscriber line is a family of technologies that are used to transmit digital data over telephone lines. In telecommunications marketing, the term DSL is widely understood to mean asymmetric digital subscriber line, the most commonly installed DSL technology, for Internet access. 8

9. Types Of Internet Services Cable Internet is a category of broadband Internet access that uses the infrastructure of cable TV network to provide Internet services. Cable Internet provides connectivity from the Internet service provider (ISP) to the end users in a similar manner as digital subscriber line (DSL) and fiber-to-the-home (FTTH). 9

10. Types Of Internet Services Satellite internet is wireless internet beamed down from satellites orbiting the Earth. It’s a lot different from land-based internet services like cable or DSL, which transmit data through wires. Since it’s the only internet service that’s available nationwide, satellite internet is often the only way to get online for many rural homes and businesses. 10

11. Types Of Internet Services 3G and 4G are both networks that connect your phone to the internet. The “G” in each stands for generation. So where 3G means 'third generation', 4G stands for 'fourth generation'. As it is with most techy things, the larger number indicates the newer, better version of a particular technology. 4G, or the current standard of cellular networks, was released in the late 2000s and is 500 times faster than 3G. It has been able to support high-definition mobile TV, video conferencing and much more. 11

12. Hardware for internet Modem Modem  is a device that enables a computer to send or receive data over telephone or cable lines. The data stored on the computer is digital whereas a telephone line or cable wire can transmit only analog data. The main function of the modem is to convert digital signal into analog and vice versa. 12

13. Hardware for internet Hub A hub is a physical layer networking device which is used to connect multiple devices in a network. They are generally used to connect computers in a LAN. A hub has many ports in it. A computer which intends to be connected to the network is plugged in to one of these ports. 13

14. Hardware for internet Router A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions on the Internet. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey. 14

15. Computer network Computer network is two or more computers that are connected with one another for the purpose of communicating data electronically. Besides physically connecting computer and communication devices, a network system serves the important function of establishing a cohesive architecture that allows a variety of equipment types to transfer information in a near-seamless fashion. Two popular architectures are ISO Open Systems Interconnection (OSI) and IBM’s Systems Network Architecture (SNA). 15

16. Classification of computer network There are three main types of computer network. LAN: (Local Area Network) 16

17. PAN A personal area network  is a network concerned with the exchange of information in the vicinity of a person. Typically, these systems are wireless and involve the transmission of data between devices such as smartphones, personal computers, tablet computers, etc. The purpose of such a network is usually to allow either transmission of data or information between such devices or to server as the network that allows further up link to the Internet. 17

18. LAN A LAN comprises cables, access points, switches, routers, and other components that enable devices to connect to internal servers, web servers, and other LANs via wide area networks. The rise of virtualization has also fueled the development of virtual LANs, which enable network administrators to logically group network nodes and partition their networks without a need for major infrastructure changes. For example, in an office with multiple departments, such as accounting, IT support, and administration, each department's computers could be logically connected to the same switch but segmented to behave as if they are separate. 18

19. MAN MAN or Metropolitan area Network covers a larger area than that of a LAN and smaller area as compared to WAN. It connects two or more computers that are apart but resides in the same or different cities. It covers a large geographical area and may serve as an ISP (Internet Service Provider). MAN is designed for customers who need a high-speed connectivity. Speeds of MAN ranges in terms of Mbps. It is hard to design and maintain a Metropolitan Area Network. 19

20. WAN WAN or Wide Area Network is a computer network that extends over a large geographical area, although it might be confined within the bounds of a state or country. A WAN could be a connection of LAN connecting to other LAN’s via telephone lines and radio waves and may be limited to an enterprise (a corporation or an organization) or accessible to the public. The technology is high speed and relatively expensive. 20

21. Benefits of Internet 21

22. Demerits of Internet Spam and advertising  22

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