Internet, History of the Internet, Network Backbone, And How The Internet Works in this article you will learn about the internet…
The internet is the network of networks around the world. It is a global network of computers. It is made up of thousands of smaller, national, regional, governmental, academic, and commercial networks.
The internet has revolutionized the computer and communication world. It is a major communication tool used by commercial enterprises, and government agencies to support trade operations, and interaction with customers and suppliers. Many individuals use the internet every day, at work and at home. Throughout the world the internet is used as a primary source of communication and information services more than 650 million individuals, worldwide, use the internet.
A large number of books, newspapers, magazines, encyclopedia, and other types of materials are available in electronic form on the internet. We can find information about almost anything in the world and can access latest information or news on any topic. It means that internet is an ocean of knowledge.
In addition to finding information, we can communication with other people around the world. Due to internet, out world has become a “Global Village”. Now information can be accessed from any part of the world.
Brief History of the Internet:
The internet did not come into being just overnight – rather it was the end result of research that had been in place since the late 1950s.
The cold war between the USA and Russia began in the mid of 1940s. in 1957, Russia launched Sputnik, the first artificial earth satellite. In response to the launching of Sputnik, the Americans established the advanced research projects Agency (ARPA) in 1958, ARPA was given the task of developing a communication system.
In 1964, the USA made a military intervention in Vietnam. In 1968, Russia also made a military intervention in Czechoslovakia. America wanted to communicate with its armed forces in Vietnam. So at the end of 1960, internet history began.
In 1964, Paul Baran Published a paper on distributed communication networks. It was a theoretical idea of data transfer.
In 1969, the Defense Advanced Research Project Agency (DARPA) of the USA established a small computer network, it was named ARPANet. ARPANet stands for Research Project Agency Network. ARPANET was a network of four computers.
CSNet inter-network was created between 1975 and 1977, by a team of Wisconsin university. CSNet stands for Computer Science Network. This network was established to promote and to make research in information technologies.
In the 1970s Network control protocol (NCP) was developed. It was the first standard protocol for data transmission between host-to-host.
In 1974, TCP (Transmission Control Program) was designed for sharing and transferring data among different networks. In 1978, TCP was split into two parts namely;
Transmission Control Protocol (TCP)
Internet Protocol (TP)
In 1982, TCP/IP (Transmission Control Protocol/internet Protocol) became the official communication protocol.
The idea of computer networking soon became popular. During 1970s and 1980s several universities & research organizations developed their own computer networks. Similarly, many other networks for military use were also developed.
In 1986, the National Science Foundation (NSF), another federal agency of USA, established a network and named as NSFNet. It was established for academic purposes. It was accessible by everyone. Later it was expanded all over the country. A large number of networks of universities and research centers were connected to these networks, so that they could share information. This large network of computer networks was named as the internet.
The internet has grown rapidly since 1990. According to internet society (the monitoring organization), the number of computer networks in the internet is more than two million. Similarly, the number of computers that connect to these networks is more than a hundred million.
In 1991, the first www files were made available on the internet for downloading using FTP (File Transfer Protocol).
Internet Network Backbone:
The inner structure of the internet works much like a transportation system. The main communication lines carry the heaviest amount of traffic on the internet these communication lines are referred to as the internet backbone. It can also be defined as:
“the central structure or element of the network, which connect other elements of the network and handles the major traffic, is called the backbone”
The backbone is a high-speed element. It is the major communication link that ties internet servers across wide geographical areas.
How the internet works:
There is no particular organization that controls the internet different networks of private companies, government agencies, research organizations, universities etc, are interconnected. You can say that the internet is a huge collection of millions of computers, all linked together. These collection networks allow computers to communicate with each other.
A personal computer can be linked to the internet using a phone-line modem DSL or cable modem. This device is use to communicate with the server of an internet service provider(ISP). A computer in a business or university is usually connected with LAN using network interface Card ( or LAN card), the LAN of university or business is connected to the server of ISP using a high-speed phone line such as T1 line a T1 line can handle approximately 1.5 million bits per second, A normal phone line using a modem can handle 30000 to 50000 bits per second.
We make our connection to ISP and ISP make its connection to larger ISP. The largest ISPs maintain fiber-optic “backbone” for an entire region. Backbones around the world are connected through the fiber-optic lines, undersea cables, or through satellite links. In this way, every computer on the internet is connected to every other computer on the internet. The figure shows how internet works.
An organization network, through which the files and messages can be exchanged among the users of the organization only, is called the intranet. This type of network uses the same protocols as used in the internet. But through intranet the information cannot be exchanged outside the organization.
An extranet is a network of multiple intranets. It means that intranet of different companies are connected together for sharing information among them. On an extranet, each connected company gives selected rights to the employees of one or more than one company to access its intranet.
Terminologies and Tools used for the Internet:
The following basic terminologies and tools are used for the internet:-
A web server stores web pages or files and sends information over the internet in response to request from the web browser. In 1992, there were only 26 web servers in the world to publish web pages. Now-a-days millions of web servers are providing these services on the internet.
You can also set up your own web server. The web server software is available to set up a computer as web server. Your computer should be a powerful computer and permanently connected to the internet.
The tools and programs through which the user gets information from server as well as sends information to other user through server is called client. Usually the personal computers and browser programs are used to get information from the server
The computer that are connected to the internet and exchange information between users on the internet are called hosts. There is no central computer on the internet but there are millions of host computers that can both send and receive information to and from other hosts connected to the internet. In this way, each host on the internet behaves both as a server and as a client.
A web browser is software that allows the internet user to access and view web pages on the internet. The process to receive the information of web page from server on the internet is called downloading. The downloading process takes few seconds. This time depends on the speed of your internet connection and the size of graphics that a web page contains. Many web browsers are available but the commonly used web browsers are Microsoft internet explorer and netscape navigator.
The mobile devices such as cellular telephones and PDAs use a special type of browser, called a microbrowser, which designed for their small screens.
The internet protocols are set of defined rules and procedures used for communication through which internet users exchange information on the network. The first protocol was developed in early 1970s for data communication on network and was named as Network Control Protocol (NCP). Now-a-days, the commonly used protocol are:
TCP/IP : TCP/IP stands for transmission control protocol / internet protocol. This protocol enables users (or provides connectivity between browsers and servers) for data communication on the internet. TCP/IP manages the transmission of data in the internet by breaking the data into small pieces called packets. Each packet contains the following information:
- Actual data
- Sequence information used to reassemble the data at the destination etc
FTP : FTP stands for file transfer protocol. This protocol exchanges files between users, it is specially designed for uploading and downloading audio, video, graphics, and all other different types of files. The FTP software uses this protocol for transferring files on the internet. The examples of FTP software are :WS_FTP and Cute FTP.
HTTP: HTTP stands for HyperText transfer protocol. It is a protocol used for communication between browsers and web servers (e.g. for transferring information from web pages, stored on the web server, to the browser). It was developed in 1990 when World Wide Web was introduced.
HTTP uses a request / response model of communication. A browser connects with a web server by establishing a TCP connection at port 80 of the server. This port is the address at which web servers listen for browser requests. Once a connection has been established, a browser sends request (URL request) to the server. The server processes the browser’s request and sends a response back to the browser.
SMTP: SMTP stands for Simple Mail Transfer Protocol. This protocol is used to send and receive e-mail on the internet.
NNTP: NNTP stands for network news transfer protocol. This protocol is used to exchange message on the worldwide news bulletin board.
The documents on the web are called web pages. These are electronic documents stored on the special servers known as web servers. The web servers are permanently connected to the internet.
A web page may contain simple text, images, and hyperlinks (or simply links). The web pages are linked to one another using hyperlink.
A collection of related web pages stored on a web server is called website. The web browser is used to access website. A website may contain many web pages.
The main page or title page of a website that contains the links of other web pages is referred to as home page. The home page is downloaded first when you enter the URL address of the website. The other pages of the website are visited through home page because it contains the links of other pages. You can say that a home page is similar to the table of contents for the website.
HTML stands for HyperText Markup Language. It is fundamental language, which is used to design web pages.
Frames are used in a web document to divide the browser window into different sections. In each section, a web page can be displayed. So at the same time multiple pages can be displayed in a browser window.
A person who develops and maintains websites is known as web master. Web master and other web developers design web pages / website.
URL stands for Uniform Resource locator. It is a unique address of web page or any other file on the internet. It is used by the browser of client computer to access the documents stored on the host or web server. Following are some important URL addresses as an examples:
as shown in the above URLs, each URL may have the following parts:
- Prefix with protocol identifier, such as “https” or “ftp” followed by a colon and double slashes (//).
- The domain name.
- The path of the document. The forward slash (/) character is used in the document path.
- Addressing Schemes:
The purpose of the internet is to establish communication between large numbers of computer all over the world. Computer can send and receive data to each other. On the internet, every computer has a unique address. The computers communicate with each other with the references to their addresses. These addresses are assigned to the computers on the internet according to some set of rules. These rules are called addressing schemes. There are two types of addressing schemes recognized on the internet. These are:
- DNS Addressing
IP stand for Internet protocol. It is a unique identifier for a host or node on the internet. It is numerical address with four number separated with dots. A typical IP address looks like this 192.168.1.1 the four numbers in an IP address are called octets. They can have values between 0 and 255. Every machine on the internet has a unique IP address. A server has Static IP address that does not change. When a home computer connects to the ISP, it is also assigned an address by ISP. This IP address is unique for that session It is not static, when the same computer will be connected next time, a different IP address will be assigned to it.
DNS stands for Domain Name System. IP addresses are difficult to remember for the users. Every server (or host) on the internet also has a unique name. the human-readable name assigned to the computer (server) on the internet is called the domain name. it is a common and unique text name and is an alternative to an IP address. For example, “yahoo.com” is a permanent, human-readable name it is easier to remember than an IP address. The domain name has two parts a hostname and domain. The domain is also known as the top-level domain (TLD) the top-level domain specifies the type of domain such as type of organization. It comes at end of domain name separated with dot (.) the commonly used top-level domains are ( .com ) , (.edu) , (.gov), (.org)
A way of assigning a domain name to IP addresses is called domain name system (DNS). DNS server is used to store domain names and their corresponding IP addresses. The DNS server translates the domain name into the corresponding IP address.
The method that allows for creating link of one section of document to another section or to another document is called the hyperlink or simply it is called link. The hyperlink may be created on any text or picture. The mouse pointer changes its shape (usually changes to hand shape) when it is over the link. It shows that the text or image is clickable. When the link is clicked, you jump to the section or document that has the address under the link. Under the link, there may be URL of any web page or the specific section name of the same document.
ISP stands for Internet Service Provider. It is a company that provides the internet connections to the users. There are many ISP companies in each big city of the countries of the world. You have to get an internet connection from ay ISP company of your local city to connect to the internet. The ISP company will provide you, a username for your identification, a password for your account security and a telephone number to connect to its server computer. The popular ISPs in Pakistan are Comsats, WOL, Brain Net and PTCL etc.
How to Connect to the Internet:
You must have an internet account of any ISP (Internet Service Provider) company to connect to the internet. In Pakistan, there are many ISP companies. Most Internet Service Providers have their internet cards available in your local market having an amount of Rs,10 to Rs,100. The rate of internet charges is from Rs.2 to Rs.5 per hour. Purchase the car and follow the instructions given on the card. It is a very easy and fast way to get an internet account for internet connection. The following hardware and software are required to connect to the internet:
- A computer running under windows operating system like windows 2000 and Windows XP.
- A telephone line to connect to the ISP server.
- A modem to exchange information between the user’s computer and server of ISP through a telephone line.
- Web Browser for browsing the internet like internet Explorer.
- TCP/IP protocol. The windows operating system already includes the TCP/IP.
- Dial-up the software to establish a connection between your personal computer and the server of the ISP. In the windows operating system, you may need to run a wizard in order to activate this software.
The internet consists of two sides: these are server-side and client-side.
Server Side: it consists of a web server, a database server, and a software development machine.
Client-Side: it consists of a computer that sends requests to the server and receives information from the server.
Accessing the internet:
the internet can be accessed through different ways to send and receive information. The most popular method are:
- connecting through the modem.
- Connecting through a LAN.
- Connection through high-speed lines.
Connecting through a Modem:
You can connect to the internet through the modem. In this way, the serial data communication port and dial-up utility program are used. Most of the individual users connect to the net by using a telephone line, a modem of 56 kbps and a SLIP (Serial Line interface protocol) or PP (Point-to-point protocol) account. Most of the ISP companies provide these types of connections for home users and businesses. When you connect to the ISP’s server computer, by dialing through a telephone number, you have to give your username, a password provided by that ISP Company.
Connecting through a LAN:
You can connect to the internet through a LAN if LAN uses TCP/IP protocols and has a net connection. This type of connection is commonly used by businesses to provide LAN users with internet access. Actually, the computer on the LAN connects to the internet through a router or modem
Connection through High-Speed Lines:
The data accessing speed of the modem connection is very slow. It is fine to access text data but it is not suitable to access graphics files or data like audio and video. Today connections of dedicated high-speed lines are available from different telephone companies, cable TV services, etc. You can access data with very high-speed, i.e. 20 or more times faster by using fiber optics, microwaves, satellites, etc.
Communication on the internet:
TCP/IP is the only protocol used to send information around the internet. This protocol is responsible for routing information from one site to another, and for transmitting the information. The HTTP protocol defines how data must be transmitted between the client and the server via TCP/IP. The TCP/IP is used to set up communication between a client and a server on the internet. It breaks up data into datagrams (packets of data) and guarantees that the data is correctly received at its destination.
Advantages of the Internet:
The internet provides many facilities to the people. The main advantages of the net are as follows:
You can share information with other people around the world. The scientists or researchers can interact with each other to share knowledge and to get guidance etc. sharing information through the internet is a very easy, cheap, and fast method.
Collection of Information:
A lot of information of different types is stored on the web servers on the internet. It means that billions of websites contain different information in the form of text and pictures. You can easily collect information on every topic of the world. For this purpose, special websites, called search engines are available on the internet to search for information on every topic of the world. The most popular search engines are google.com, altavista.com, search.com, yahoo.com, ask.com, bing.com, etc. the scientists, writers, engineers, students, and many other people use these search engines to collect the latest information for different purposes. Usually, the information on the internet is free of cost. The information on the net is available round the clock.
News on the internet:
You can get the latest news about the world on the internet. Most of the newspapers in the world are also available on the internet. They have their website from where you can get the latest news about the events happening in the world. These websites are periodically updated or they are immediately updated with the latest news when any event happens around the world.
Searching Jobs on the internet:
You can search for different types of jobs all over the world. Most of the organization/departments around the world advertise their vacancies on the internet. The search engines are also used to search the jobs on the internet. You can apply for the required jobs through the net.
Advertisement on the internet:
Today, most commercial organizations advertise their products through the internet. It is a very cheap and efficient way of advertising for the products. The products can be presented in an attractive and effective way for people around the world.
You can communicate with other people through the internet around the world. You can talk by watching one another, just as you are talking with your friends in your drawing room. For this purpose, different services are provided on the net such as;
- Video conferencing
- Internet telephony etc.
Entertainment on the internet:
The Internet also provides different types of entertainment to the people. You can play online games. Similarly, you can see movies, listen to music, etc. you can also make new friends on the net for enjoyment.
The Internet provides the facility to get online education. Many websites of the different universities provide lectures and tutorials on different subjects or topics. You can also download these lectures or tutorials on your own computer. You can listen to these lectures repeatedly and get a lot of knowledge. It is a very cheap and easy way to get an education.
Today, most of the universities and education boards display results on the internet. The students can check their results in any part of the country or world.
Online Airlines and Railway Schedules:
Many Airline companies and Pakistan railway provide their schedules of flights and trains on the internet.
Online Medical Advice:
Many websites are also available on the internet to get information about different diseases. You can consult a panel of online doctors to get advice about any medical problem. In addition, a lot of material is also available on the net for research in the medical field.
Disadvantages of the Internet:
Although the internet has many advantages it has some disadvantages too.
The main disadvantages are:
Today, the internet is the most common source of spreading viruses. Most of the viruses transfer from one computer to another through e-mail or when information is downloaded on the net. These viruses create different problems on your computer. For example, they can affect the performance of your computer and damage valuable data and software stored on your computer.
internet Security Problems:
The valuable websites can be damaged by hackers and your valuable data might be deleted. Similarly, confidential data may also be accessed by unauthorized persons.
Some websites contain immoral material in the form of text, pictures or movies, etc. these websites damage the character of the new generation.
Filtration of Information:
When a keyword is given to a search engine to search for information on a specific topic, a large number of related links are displayed. In this case, it becomes difficult to filter out the required information.
Accuracy of Information:
A lot of information about a particular topic is stored on the websites. Some information may be incorrect or not authentic. So, it becomes difficult to select the correct information. Sometimes you may be confused about the accuracy of information.
Wastage of Time on internet:
A lot of time is wasted in collecting information on the internet. Some people waste a lot of time chatting or playing games. At home and in offices most of people use the internet without any positive purpose.
English language problems:
Most of the information on the internet is available in the English language. So, some people cannot avail of the facility of the net.
Services Provided by the Internet:
The Internet plays a very important role in our society. It provides a lot of latest informative information about the business, education, etc. it has become the main medium for advertisement and communication between users, etc. the main services provided by the net are:
- World Wide Web (WWW)
- E-mail (Electronic mail)
World Wide web:
The World Wide Web is simply referred to as web. It is the latest addition to the internet to exchange information. The web is a vast network of HTTP servers (Web servers) that stores documents called web pages and these are accessible on the net. It is abbreviated as www or 3w. it is the easiest way to search and to get information on the internet.
News group are discussion groups or forums. They provide the services to exchange messages on the internet about a particular subject. This facility is provided on the internet on special servers known as News servers. Different newsgroups are available for different purposes. For example, a newsgroup provides the services to exchange information about business and another provides the services about current affairs, etc. you can become a member of any newsgroup on the net for reading and posting messages on the newsgroup. Usually the news client program “Microsoft internet News” is used to read & write articles in newsgroups.
FTP stands for File Transfer protocol. It is a way of transferring files to others through internet. The files are stored a special type of server called the FTP server. The browsers can be used to transfer file from FTP server to the client computer but it is a slow process to transfer files. A lot of FTP client programs of different software companies are available through which files can be downloaded from FTP server into your local computer very easily & quickly. Similarly, the files from your computer can be uploaded to the FTP server. Examples of these special programs are WS_FTP and Cute FTP.
The Internet also provides the facility to net users to chat with people online all over the world. Different programs like MSN Messenger, Yahoo Messenger, ICQ, AOL online, etc, are available for chatting on the internet. You can add the names of your friends or other people to these programs. These programs notify you when one or more people are online and then allow you to exchange messages or files with them or join a private chat room. The chat room allows users to participate in a chat on the net. A chat room is an area on the web where you can talk with people online. You send messages by typing with a keyboard to the online people and receive messages from others instantly. Some chat rooms support voice chats and video chats where you talk with people as well as watch them.
E-Commerce stands for Electronic Commerce, it is a very important service provided by the internet through which financial transactions are carried out over the internet. It is the modern way to run a business on an international basis. When business is conducted with the help of computer networks, this activity is usually termed as e-commerce or e-trade. Examples of E-commerce are; online shopping, online advertising, online banking, etc.
Through e-commerce, goods can be purchased and sold from anywhere in the world. Credit cards are used for payments. It is estimated that the size of e-commerce is growing at a rate of 10% to 15% per month in the world.
telnet is an internet service (or tool ) that is used to login and run commands (or programs) on a remote server on the internet. Through this service, you can also access information on the net. You run the telnet client application on your computer. The telnet provides you a prompt on your screen and you can access the host computer by giving commands through this prompt. You will feel that you are sitting in front of the host computer and operating it. When you send commands to the host through this service, information is accessed from host and displayed on your own computer screen.
When telnet client program is run on your local computer, you have to give your account name (user name) and password to start the operating session. The expert users mostly use this service. In some remote servers, this service is not allowed.
Gopher is an internet service. It organizes resources into multilevel menus to make finding information easier on the internet. Before Gopher, it was difficult to find information on the net.
E-mail stand for electronic mail. It is the most popular service or facility provided by the net. We can send and receive messages anywhere in the world. The message can be sent to many persons with a single email.
You can also send documents, pictures, audio and video files via e-mail by attaching the file with email. It is also possible to send or receive email messages through a mobile phone. The users often begin search from the top-level and then moves inside the directory structure step-by-step. For example, to search information about health, the user selects the top-level of the directory “Health”. He/she then goes through its sub-categories step-by-step to search the required information.