How does the Internet Work
Internet, often called as network of computer networks, requires computers, connected to each other and is able to talk to each other. Internet is a worldwide network. Internet is based on a uniform language which is TCP/IP (Transmission Control Protocol/ Internet Protocol) and is understood by all internet computers. All the Internet applications such as e-mail, World Wide Web (WWW) etc… make use of this language only.
Each computer connected to the Internet always has a unique address. Internet addresses are in the form “—. —. —. —“, where “—“must be a number from 0 – 255. This address is known as an IP address (Internet Protocol address). If a user connects to the Internet through an Internet Service Provider (ISP) then the user is usually assigned a temporary IP address for the duration of his or her session. If the user is connected to the Internet from a local area network (LAN) then the user’s computer might have a permanent IP address or it might obtain a temporary one from a Dynamic Host Configuration Protocol (DHCP) server. In any case, if the user is connected to the Internet then his or her computer has a unique IP address.
Internet hostnames are composed of parts separated by dots. A domain is a collection of machines that share a common name suffix. Domains can live inside other domains. For example, the machine www.abcd.edu lives in the .abcd.edu subdomain of the .edu domain.
The whole network of programs and databases that cooperates to translate hostnames to IP addresses is called ‘DNS’ (Domain Name System). Each domain is defined by a primary name server that knows the IP addresses of the other machines in the domain. The primary name server may have backups in case it goes down.
The browser sends the command to the Web Server and the command is made into a packet, a block of bits and is wrapped with three important things; the source address (the IP address of sender’s machine), the destination address (IP address of receivers machine), and a port number that indicates that it’s a World Wide Web request.
The TCP/IP is responsible for labeling individual packets with the source address and destination address of two computers exchanging information over a network and also provides reliability. Hyper Text Transfer Protocol (HTTP) is used by web to supports hypertext documents.