Internet Evolution:

Internet Evolution:

The Internet is a network of networks

* Computer users on the Internet can contact one another anywhere in the world-In Internet a huge resource of information is accessible to people across the world—Information in every field starting from education, science, health, medicine, history, and geography to business, news, etc. can be retrieved through Internet— You can also download programs and software packages from anywhere in the world — In 1969 Department of Defense (DOD) of USA started a network called ARPANET (Advanced Research Projects Administration Network )— Around 1970, NSFNET (National Science Foundation Network) was created. With the advancement of modern communication facilities,— By 1990 many computers were looking up to NSFNET giving birth to Internet— Internet is not a governmental organization.— The ultimate authority of the Internet is the Internet Society.— This is a voluntary membership organization whose purpose is to promote global information exchange.— Internet has more than one million computers attached to it.— Ten years of research brought Local Area Ethernet Networks (LANs) and workstations were developed to get connected to LAN.— Computers connected to ARPANET used a standard or rule to communicate with each other with NCP (National Control Protocol).— Protocol is a network term used to indicate the standard used by a network for communication.— Rapid change in information technology suppressed NCP and brought TCP/IP (Transmission Control Protocol/Internet Protocol) in to the world of networking— The Internet is a rare example of a large democracy with no state of head, no official censors, no bosses, no board of directors. Nobody controls the Internet and in principle, any computer can speak to any other computer, as long as it obeys the technical rules of the TCP/IP protocol.— This freedom of Internet helped it to move out of its original base in military and research institutions, into elementary and high schools, colleges, public libraries, commercial sectors.

Basic Internet Terminology:

Blog - A blog is information that is instantly published to a Web site. Blog scripting allows someone to automatically post information to a Web site. The information first goes to a blogger Web site. Then the information is automatically inserted into a template tailored for your Web site.

Bookmark – a way of storing your favorite sites on the Internet. Browsers like Netscape or Internet Explorer let you to categorize your bookmarks into folders.Browser – A software program that allows users to access the Internet. Examples:Non-graphical a user interface for computers which allows you to read plain text, not pictures, sound, or video, on the Internet. It is strictly text based, non-Windows, and does not place high memory demands on your computer. An example is lynx .(http://lynx.browser.org/)Graphical a user interface for computers which enables people to see color, graphics, and hear sound and see video, available on Internet sites. These features are usually designated by underlined text, a change of color, or other distinguishing feature; sometimes the link is not obvious, for example, a picture with no designated characteristic. Examples are Netscape and Internet Explorer.CGI (Common Gateway Interface script) – a specificiation for transferring information between a Web server and a CGI program, designed to receive and and return data. The script can use a variety of languages such as C, Perl, Java, or Visual Basic. Many html pages that contain forms use a cgi program to process the data submitted by users/clients.Chat – real-time, synchronous, text-based communication via computer.

Cookie – Information (in this case URLs, Web addresses) created by a Web server and stored on a user’s computer. This information lets Web sites the user visits to keep of a user’s browsing pattterns and preferences. People can set up their browsers to accept or not accept cookies.

Domain Name – A method of identifying computer addresses. Your e-mail address has a domain address. If you have an “edu” at the end of your e-mail address that means your account is affiliated with an educational institution. A “com” extension means you have a business account. A government account has a .gov suffix.

FTP – Using file transfer protocol software to receive from upload) or send to (download) files (text, pictures, spreadsheets, etc.) from one computer/server to another. Home page - Generally the first page retrieved when accessing a Web site. Usually a “home” page acts as the starting point for a user to access information on the site. The “home” page usually has some type of table of contents for the rest of the site information or other materials. When creating Web pages, the “home” page has the filename “index.html,” which is the default name. The “index” page automatically opens up as the “home” page.

HTML – A type of text code in Hypertext Markup Language which, when embedded in a document, allows that document to be read and distributed across the Internet.HTTP – The hypertext transfer protocol (http) that enables html documents to be read on the Internet.

Hypertext – text that is non-sequential, produced by writing in HTML (Hypertext Markup Language) language. This HTML coding allows the information (text, graphics, sound, video) to be accessed using HTTP (Hypertext Transfer Protocol).Hyperlink – Text, images, graphics that, when clicked with a mouse (or activated by keystrokes) will connect the user to a new Web site. The link is usually obvious, such as underlined text or a “button” of some type, but not always.Instant Messaging (IM) – a text-based computer conference over the Internet between two or more people who must be online at the same time. When you send an IM the receiver is instantly notified that she/he has a message.

IP Address – (Internet Protocol) The number or name of the computer from which you send and receive information on the Internet.Modem – A device that connects your computer to the Internet, when you are not connected via a LAN (local area network, such as at work or on a campus.) Most people connect to a modem when using a home computer. The modem translates computer signals to analog signals which are sent via phone lines. The telephone “speaks” to the computer/server which provides your Internet access.

URL – A universal resource locator (a computer address) that identifies the location and type of resource on the Web. A URL generally starts with “http.”Intranet: It is a relatively smaller private network that uses the Internet protocols and connectivity. It is an extension of the Internet and is privately used by organizations.

Web Server: A web server is a computer program that accepts HTTP requests from web clients and provides them with HTTP responses.

IP Address: It is a way of numerically identifying an entity on a computer network. The original addressing system known as IPv4, used 32 bit addresses. With the growth of the Internet, IPv6 came to be used wherein the addresses are composed of 128 bits.

You might want to know how to find your IP address.Internet Service Provider: A company, which provides users with an access to the Internet, is known as an Internet service provider or Internet access provider. ISP, as it is called, offers email accounts and other services like remote storage of files for its customers. Here is a word about choosing a cheap ISP.Internet Address— Every page on the Internet has a unique address.— This address is used get the web page for user from Internet.— The address on the Internet is known as URL (Uniform Resource Locator).— A typical Internet address or URL would look like; http://www.mans.edu.eg/facscim/arabic/— The URL contains the components that specify the protocol, server, and pathname of an itemURL parts— The protocol is followed by a colon (http:),— The server is preceded by two slashes (//www.mnmjec.edu.)— Each segment of the pathname is preceded by a single slash /facscim/ /english/Tables/Default.htm).— A protocol is set of rules that tells the computer know how to interpret the information at that address— The first component, the protocol, defines the manner for interpreting computer information.— Many Internet pages use HTTP (HyperText Transfer Protocol).— Other common Internet protocols that one might come across are FTP (File Transfer Protocol),— NEWS (Usenet news groups protocol), and— GOPHER (an alternative transfer protocol). Gopher protocol is mostly out of date now.— The second component, of the address is the server (www.mnmjec.edu), identifies the computer system that stores the information you seek and is always preceded by two slashes.— A server is a computer that has information stored on it and sends it to the client, when a request is made.— Each server on the Internet has a unique address name whose text refers to the organization maintaining the server.— Most of the Web pages will have .htm or .html as their secondary or extension name.

Getting connected to Internet ApplicationsTypes of Internet Connections

There are two main ways for users to connect to the Internet: through dial-up access or by using a LAN connection.Dial-up Access Dial-up access allows access to the Internet over a standard telephone line by using a computer and a modem to dial into an ISP or VAN connection. Dial-up access is a feature typically included with the software provided by an ISP. Using a regular telephone line is usually the slowest telecommunications medium for setting up an individual Internet account through a dial-up ISP.

Local Area Network (LAN) Connection LAN connections provide faster and more direct Internet access by connecting users to an ISP on a direct wire, at speeds 30 or more times faster than can be achieved through a dial-up modem. Because they are more expensive than dial-up access, LAN connections are more commonly found in the workplace. Despite the increased cost there are approximately forty million LAN users in the United States using cable and DSL connections to connect from their homes.

Cable Modem Television cable companies provide a special modem and software for broadband (high-speed) Internet access. This service offers the advantage of simultaneous Web access and telephone calls, but is not available everywhere. In addition, the service slows down as more subscribers sign up in a neighborhood or location. The cost is about $50 monthly, plus a possible installation fee.

Digital Subscriber Line (DSL) DSL Internet service is as fast as cable modem and provides simultaneous Web access and telephone use, but the service is usually available only to users within three miles of the telephone carrier’s central switching office. The line is dedicated to one household, and is not shared with neighbors. DSL service costs around $50 monthly, plus an installation fee.Wireless The fastest growing segment of Internet service involves wireless connections to the Internet. Thousands of Wireless “hot-spot” portals are springing up, allowing access in public places and even aboard airplanes.— (i) Gateway Access— Gateway Access is also known as Level-One connection.— It is the access to the Internet from a network, which is not on the Internet.— The gateway allows the two different types of networks to “talk” to each other. But the users of the Gateway Internet have limited access to the Internet.— They might not be able to use all the tools available on Internet. The local Internet Service Provider (ISP) normally defines this limitation.Dial-up Connection— ‘Dial-up’ connection is also known as Level Two connection.— This provides connection to Internet through a dial-up terminal connection.— The computer, which provides Internet access is known as ‘Host’ and the computer that receives the access, is ‘Client’ or ‘Terminal’.— The client computer uses modem to access a “host” and acts as if it is a terminal directly connected to that host.— This type of connection is also known as ‘Remote Modem Access’ connection.— And the host to which the client gets connected is actually connected to the Internet by a full time connection (See Leased Connection).— In dial-up connection to Internet, Host carries all the command that are typed on a client machine and forward them to Internet.— It also receives the data or information from the Internet on behalf of the ‘Client’ and passes it to them. The client computer acts as a ‘dumb’ terminal connected to remote host.— This type of connection can further be divided into two categories.Shell Connection— In this type of Internet Connection, the user will get only textual matter of a Web Page.— This connection does not support Graphics display. However the user will be able to surf the Internet, do FTP, receive mail.— Shell Accounts were the only type of Internet access available for many years before the Internet entered in to the world of graphics and became more users friendly.TCP/IP Connection— Today’s graphical World Wide Web browsers provide easier access with multimedia sound and pictures.— The major difference between Shell and TCP/IP account is that, Shell account can only display text and does not support graphics display, whereas TCP/IP can display both.— Hence it is more popular Internet connection. Shell accounts are slowly phasing out from the Internet scenarioTo access any of these dial-up accounts you need the followings;$ computer, WebTV, personal digital assistant (PDA), or Web phone$ dial-up modem, digital subscriber line (DSL) modem, or cable modem$ telephone line or cable connection$ telecommunications software$ Web browser$ an account with an Internet Service Provider (ISP)Leased Connection— Leased connection is also known as direct Internet access or Level Three connection. — It is the secure, dedicated and most expensive, level of Internet connection.— With leased connection, your computer is dedicatedly and directly connected to the Internet using high-speed transmission lines.— It is on-line twenty-four hours a day, seven days a week.— Leased Internet connections are limited to large corporations and universities who could afford the cost.Newer Internet ApplicationsNot only does the content of the Internet change daily, but they very way in which the Internet is used and understood as a communication medium is constantly evolving.Peer-to-Peer File SharingPeer-to-Peer (P2P) file sharing allows people to download material directly from other users’ hard drives, rather than from files located on Web servers. Napster is famous for pioneering P2P file sharing.Internet TelephonyInternet telephony is another increasingly popular way to use the Internet. By using this technology, also called Voice over IP (VoIP), two or more users with sufficiently good connections can use the Internet to make telephone calls around the world. Once their voices are digitized and broken down into packets, they can be transmitted anywhere, just like any other form of data. There are no long distance telephone charges, and users only pay their normal ISP connection fees.