3.1 INTERNET
3.1.1 What is the Internet?
The Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP).
It is a “network of networks” that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked web pages and other resources of the World Wide Web (WWW).
The Internet and the World Wide Web are not synonymous. The Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc. In contrast, the Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is one of the services accessible via the Internet, along with various others including e-mail, file sharing, online gaming and others described below.
America Online, Comcast, Earthlink, etc. are examples of Internet service providers. They make it physically possible for you to send and access data from the Internet. They allow you to send and receive data to and from their computers or routers which are connected to the Internet.
World Wide Web is an example of an information protocol/service that can be used to send and receive information over the Internet. It supports:
• Multimedia Information (text, movies, pictures, sound, programs . . . ).
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• Hypertext Information (information that contains links to other information resources)• Graphic User Interface (so users can point and click to request information instead of typing in text commands).
The server software for the World Wide Web is called an HTTP server (or informally a Web server). Examples are Apache and IIS. The client software for World Wide Web is called a Web browser. Examples are: Netscape, Internet Explorer, Safari, Firefox, and Mozilla. These examples are particular “brands” of software that have a similar function, just like Lotus 123 and Excel are both spreadsheet software packages.
3.1.2 Internet Structure
The Internet is an international network of computers connected by wires such as telephone lines. Schools, businesses, government offices, and many homes use the Internet to communicate with one another. You have access to the Internet when you work in one of this university’s computer labs. You also may have access at home or in your residence hall. If not, you can obtain access once you have three things. First, you need a computer and a modem, a device that allows you to connect your computer with the Internet. Many new computers have built-in modems. Second, you need a browser, a piece of software that allows you to view information on the Internet. Many new computers also come with a browser, usually Internet Explorer. You also can download another popular browser, Netscape Navigator, from the Internet for free. Finally, you need to subscribe to an Internet Service Provider, or ISP, such as America Online or Carolina Online.
One popular component of the Internet is electronic mail, or e-mail, which people at separate locations can use to send messages to one another. In general, each of these people has an e-mail address, which usually looks something like this:
[email protected]. The first part of the address (.mark.canada) specifies the individual user, and the rest of the address refers to the server (uncp.edu), which is a computer that can store a lot of information.
In addition to allowing people to send e-mail messages to one another, the Internet also allows organizations and individuals to post information about themselves so that others can see it. For example, many companies post pictures and descriptions on World
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Wide Web sites. In fact, you can set up your own World Wide Web site by reserving space on a server. To understand how this process works, imagine that you wanted to store some articles you have written at a library so that people could come and read them.
First, you would need to obtain permission from the librarians, who would assign you a folder where they would store your articles. Whenever you finished a new article, you would put a name on it and send it to the librarians, who would then place it in your folder.
When people wanted to read one of these articles, they would need to know the address of the library, the name of your folder, and the name of the specific article they want to read. When they supplied this information, the librarian would give them the article they want.
The World Wide Web works the same way. First you need to identify an Internet company (librarian) and ask permission to save Web pages (articles) on its server (library).
The company (librarian) then assigns you a directory (folder) where it will store your Web pages (articles). As you create each Web page (article), you give it a filename (name) and publish it on the server (send it to the library). When people want to read your Web page (article), they need your Web address, sometimes called a Uniform Resource Locator, or URL. The URL consists of the domain name of the server (address of the library), name of your directory (name of your folder), and the filename of the particular Web page (name of article).
3.1.3 The Internet and its Characteristics
The Internet by the late 1990s has evolved into a complex environment. Originally a military communication’s network it is now routinely used for five types of operations: (i) long-distance transactions (e.g. e-commerce, form-filling, remote work, entertainment);
(ii) interpersonal communication; (iii) data storage; (iv) research (i.e. data finding); (v) remote data access and downloading.
The Internet is a dynamic and mercurial system endowed with a number of traits.
These are:
1. Technological neutrality. The Internet joins together computers of various sizes and architectures. They may run on various operating systems and utilise a great variety of communication links.
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2. Built-in piecemeal change and evolution. The Internet is not a one-off development. It is an energetic, polycentric, complex, growing, and self-refining system. It is a network which is geared to expansion and growth. It is a system which scales up extremely well.3. Robustness and reliability. All basic technical features of the Net such as the TCP/IP (transfer control protocol/internet protocol) (Kessler and Shepard 1997), the multiplicity of routes followed by the packet-switched data, and the sturdiness of related software are designed to eliminate errors, to handle unexpected interruptions and interferences, to advise users of encountered difficulties and to recover gracefully from any disasters and down-times.
4. Low cost. The Internet makes new uses of old technologies (standalone computers, operating systems, telecommunication networks). Whenever possible, Internet operations piggyback on already existing solutions. They rely on modularised, configurable, easy-to-replace, and easy-to-upgrade off-the-shelf software and hardware.
5. Ubiquity. The robustness, modularisation and low cost of the system is coupled with the growing densities of dedicated computer lines, network backbones, as well as wired and wireless phone networks. This means that Internet-enabled tools are deployed in ever growing numbers in an ever widening range of environments
3.1.4 The Internet Tools and their Characteristics
The evolution of the Internet is punctuated by the introduction and mass acceptance of such key resources and tools as Unix, Email, Usenet newsgroups, Telnet, Listserv Mailing List Software, File Transfer Protocol, Internet Relay Chat, WAIS, Gopher, WWW, and more recently by the Altavista search engine, Java language
UNIX
The foundations of an operating system called Unix were laid at AT&T Bell Laboratories in 1969. Unix is not a product of Internet culture. It is its catalyst and cornerstone. Internet culture owes Unix a major debt in the four areas. These conceptual and procedural debts are: multitasking, community fostering, openness and extensibility, and public access to the source code. Let’s briefly look at each of these debts.
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Unix was one of the first operating systems which embodied the principle of multitasking (time-sharing). In most general terms it means that several users could simultaneously operate within a single environment and that the system as a whole coped well with this complicated situation. Unix was the first operating system which demonstrated in practical terms robustness and tolerance for the variety of it’s users simultaneous activities.
Email is the first of the Internet’s tools dedicated to the provision of fast, simple and global communication between people. This revolutionary client/server software implied for the first time that individuals (both as persons and roles) could have their unique electronic addresses. Within this framework messages were now able to chase their individual recipients anywhere in the world.
The initial format of email communication was that of a one-to-one exchange of electronic messages. This simple function was subsequently augmented by email’s ability to handle various attachments, such as documents with complex formatting, numbers and graphic files. Later, with the use of multi-recipient mailing lists electronic mail could be used for simple multicasting of messages in the form of one-to-many transmissions.
Usenet Newsgroups
Usenet (Unix Users Network), the wide-area array of sites collating and swapping UUCP-based messages was pioneered in 1979. Usenet was originally conceived as a surrogate for the Internet (then called ARPANET). It was to be used by people who did not have ready access to the TCP/IP protocol and yet wanted to discuss their various Unix tools. It was only in 1987 that the NNTP (Network News Transfer Protocol) was established in order to enable Usenet to be carried on the Internet (i.e. TCP/IP) networks (Laursen 1997).