What is Internet and how it works?
Ok. On the face of it, it seems silly to even ask this. I am WE KNOW what Internet is. (“It’s this thing..this thing…umm..on my computer…that let’s me..facebook?”). OK fine. But how does it work. Come on. We must have all wondered about it sometimes. I am sure many know some bits of it. I was faced with this question by my mentor. Given the amount of hesitation and uncertainty I had in explaining it. I decided to read and write about it. So here it is –
The name is short form for internetworking. It’s a publicly accessible network for an interconnected computer networks which communicates by ‘packet switching’ communication method (transmits data in a sizable unit called ‘packets’) using Internet Protocol, a protocol standard meant for Internet, for routing across network boundaries.
Internet Protocol (IP) uses the Internet Protocol Suite which classifies the protocols into four hierarchical layers, each layer defining the scope and reach of the protocols as suggested in their name.
Lowest communication layer is the Link layer which consists of physical components that link up computers (LAN functions at this level). It is called link as, it provides the basic connectivity functions interacting with the networking hardware of the computer and the associated management of interface-to-interface messaging.
Next is the Internet layer provides a way of communication between multiple computers across network boundaries. This is the foundation of Internet, thus deriving its name. It uses IP-bases packets that get transported to the destination host specified by an IP address. This layer contains IP address, Internet Protocol Version 4 (IPv4) and Internet Protocol Version 6 (IPv6) which is used to identify and locate hosts on the network. IP addresses consist of four numbers separated by dot where each number is called an octet.
Above it is the Transport layer which is responsible for delivering data to the appropriate application process on the host computers via a basic data channel. It does so by establishing a numbered logical construct called port which allocated specifically for each of the communication channels an application needs. The Internet and Transport Layer combined are referred to as TCP/IP which forms the communication protocol for the Internet.
The last and topmost layer is the Application layer, which contains all protocols and methods within the context of process -to-process communication across the IP network, handles application based interactions.
Internet carries a range of information and services such as the World Wide Web, the interlinked system of hypertext documents which can be viewed as a web page via a web browser. Web pages frequently subsume other resources such as style sheets, scripts and images into their final presentation and may be retrieved from a local computer or from a remote web server. It is formatted using Hyper Text Markup Language (HTML). All aesthetics and design aspects present on the page can provided by Cascading Style Sheet (CSS) instructions.
Internet works using the client-server architect, where machines in the network are categorized into clients (which has an application or system that sends request and accesses a service made available like web browser Google Chrome) and server (which has program running to serve the requests like web server Apache). The client initiates communication requesting for a specific resource using Hypertext Transfer Protocol (HTTP) to the server, which responds back with the content of the resources. It’s important to note that while server has a static IP address, client typically have IP address assigned by the Internet Service Provider for a particular session.
This is because as the numbers may be tedious to deal with, an IP address may also be assigned to a Host name (www), which is sometimes easier to remember. Hostnames may be looked up to find IP addresses, and vice-versa. Domain Name System (DNS) maintains the domain name hierarchy and provides translation services between it and the address spaces (an example being .com). In a domain name, each word and dot combination you add before a top-level domain indicates a level in the domain structure. It is the DNS that connect to each other across the Internet and cache lookup information to make name resolution more efficient.
To make the infrastructure and make the web easier to navigate, Web servers is able store a piece of text called Cookie on a client’s hard disk. Cookies allow a Web site to store information on a user’s machine and later retrieve it. The pieces of information are stored as name-value pairs. While they are not software and cannot be programmed, carry viruses, or install malware on the client, they can be used by spyware to track user’s browsing activities.
The popularity of internet has made it possible for various methods of communication between users on different network. One of most widely used one is Email, a method of exchanging digital messages from an author to one or more recipients, which uses a Simple Mail Transfer Protocol (SMTP) for sending mail. Another one is File transfer, which is the transmitting of files over a computer network or the Internet and uses File Transfer Protocol (FTP). Another major development is Voice over Internet Protocol (VoIP), which is a range of technologies, methodologies, communication protocols, and transmission techniques for the delivery of voice communications and multimedia sessions.
A new type of networking called Peer-to-peer (P2P) has become popular, which is a distributed application architecture that partitions tasks or workloads among peers.
In summary, the functions of internet cannot be attributed to one particular element or source. It keeps developing and growing organically, providing more and more ways to link the virtual world.
So I hope it made some sense…or was helpful in someway…No? Well, it’s knowledge, so just take it and leave it at the back of your mind. May help someday.