internet

ITEC 1010 Information and Organizations

THE INTERNET


THE INTERNET

The internet A network of networks The internet transmits data from one

computer (called a host) to another Internet networks

Linked networks that work much the same way -- they pass data around in packets, each of which carries the addresses of its sender and receiver


INTERNET TODAY

Large numbers of people use the Internet all over the world. In 1995 only 16 million people accessed the Internet. But only 10 years later, more than 1 billion people had signed on as regular users. And in the next 8 years another one and half billion people were added to the ranks. The Internet became popular rapidly and now it is nearly impossible to imagine life without the convenience of the Internet. There are even people who rely so heavily on communication via the Internet that they panic when they experience a blip in service.


HOW THE INTERNET WORKS

Transport control protocol (TCP) A protocol that operates at the transport layer

and is used in combination with IP by most Internet applications

Backbone An Internet high-speed, long distance

communications links (like a bus; wire that connects nodes)

Uniform resource locator (URL) An assigned address on the Internet for each

computer E.g., http://www.facebook.com/


ACCESS TO THE INTERNET

There are many ways to access the Internet. Most online services, such as America Online, offer access to some Internet services. It is also possible to gain access through a commercial Internet Service Provider (ISP).


INTERNET SERVICE PROVIDERS

Internet service provider (ISP) Any company that provides individuals or companies

with access to the Internet Thousands of providers including large communications

companies Need an account with the ISP and software that links

with TCP/IP


ISP EXAMPLESInternet Service Provider Web Address

Airtel www.airtel.in

Vodafone www.vodafone.in

Reliance www.rcom.co.in

Tikona www.tikona.in

IBM Internet Connection www.ibm.net

AT&T WorldNet Service www.att.com

Sharq Telecom www.st.uz

MTS www.mts.ru

AWCC www.afghanwireless.com


WAYS TO CONNECT THE INTERNET Dial-up DSL – Digital Subscriber Line ADSL - Asymmetric Digital Subscriber

Line Cable - Broadband Internet Connection Wireless Internet Connections


WAY TO ACCESS THE INTERNET

ADSL


THE WORLD WIDE WEB (WWW)

The most important service provided by Internet.

The World Wide Web is a global set of documents, images and other resources, logically interrelated by hyperlinks and referenced with Uniform Resource Identifiers (URIs).

URIs symbolically identify services, and servers, other databases, the documents and resources that they can provide.

Its developed in 1989 by Tim Berners-Lee an European Particle Physics Lab (CERN) in Switzerland.


WWW TERMINOLOGY Web browser

Software that creates a unique hypermedia-based menu on your computer screen and provides a graphical interface to the Web


WWW TERMINOLOGY Web page

A screen of information sent to a requesting user and presented through a browser


WEBSITE

A Website is all the pages, images and files contained under a domain name. A website is a collection of web pages belonging to a particular person of organization .Typically the URLs of web pages share a common prefix, which is the address of the home page of the site. The home page in the “Front page” of the site and is set up to help viewers find whatever is of interest to them on that site.


HYPERLINK

Hyperlink is a reference to data that the reader can directly follow, or that is followed automatically. A hyperlink points to a whole document or to a specific element within a document. A user following hyperlinks is said to navigate or browse the hypertext.


TYPES OF HYPERLINKS Hyperlinks enable you to quickly move through a

document by clicking on a hot spot or a hyperlink or connect from one web page to another. There are three types of hyperlinks used for this purpose: Text, Graphic and Affiliate. The text hyper link is usually displayed in another color and underlined. The text link can allow you to jump around on the page or to another page in the document or on a website. The Graphic link does the same as the text link, except there is only a picture or graphic image. For example you might click on a image of a cheetah and you are taking to a page which talks about the cheetah. Affiliate links performs the same, but instead of taking you directly to the page, it accesses a database where the pages are stored and loads the page. Quality wise, text links are the best because they provide information about the link.


HYPERTEXT TRANSFER PROTOCOL

Hypertext Transfer Protocol (HTTP) is the main access protocol of the World Wide Web, but it is only one of the hundreds of communication protocols used on the Internet. Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data.


UNIFORM RESOURCE LOCATOR (URL)

A uniform resource locator, abbreviated URL, also known as web address, is a specific character string that constitutes a reference to a resource. In most web browsers, the URL of a web page is displayed on top inside an address bar. An example of a typical URL would be "http://en.example.org/wiki/Main_Page"

Every URL consists of some of the following: the scheme name (commonly called protocol), followed by a colon, two slashes, then, depending on scheme, a server name (exp. ftp., www., smtp., etc.) followed by a dot (.) then a domain name (alternatively, IP address), a port number, the path of the resource to be fetched or the program to be run, then, for programs such as Common Gateway Interface (CGI) scripts, a query string, and an optional fragment identifier.

The syntax is: scheme://domain:port/path?query_string#fragment_id


LIST OF ALLOWED URL CHARACTERS Unreserved : May be encoded but it is not necessary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

a b c d e f g h i j k l m n o p q r s t u v w x y z0 1 2 3 4 5 6 7 8 9 - _ . ~

Reserved: Have to be encoded sometimes ! * ' ( ) ; : @ & = + $ , / ? % # [ ]


DOMAIN NAME

A domain name is an identification string that defines a realm of administrative autonomy, authority, or control on the Internet. Domain names are formed by the rules and procedures of the Domain Name System (DNS). Technically, any name registered in the DNS is a domain name. Sometimes, the term ADministrative Management Domain (ADMD) is used to refer to the realm of administrative autonomy. The term Fully Qualified Domain Name (FQDN) denotes a domain name with no omitted parts.


DOMAIN AFFILIATIONSDomain Affiliationsarts cultural and entertainment activitiescom business organizationsedu educational sitesfirm businesses and firmsgov government sitesinfo information service providersmil military sitesnom individuals net networking organizationsorg organizationsrec recreational activitiesstore businesses offering goods for purchaseweb entities related to World Wide Web activities

net networking organizations


SEARCH ENGINES Search engines

A search tool for the Web (like card catalogs in libraries) E.g.,

Google http://www.google.comBing http://www.bing.comYandex http://www.yandex.comYahoo! http://www.yahoo.comHotbot http://www.hotbot.comInfoseek http://www.infoseek.comLycos http://www.lycos.comWebcrawler http://www.webcrawler.com


INTERNET SERVICES

E-mail Telnet FTP Usenet and newsgroups Chat rooms Internet phone Internet videoconferencing Content streaming


INTERNET SERVICES

Internet telephony Also called voice-over-IP (VOIP)

Technology that enables network managers to route phone calls and fax transmissions over the same network they use for data


VOIP ‘DISCUSSION’

Internet telephony is a category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls. For users who have free, or fixed-price, Internet access, Internet telephony software essentially provides free telephone calls anywhere in the world. To date, however, Internet telephony does not offer the same quality of telephone service as direct telephone connections.

There are many Internet telephony applications available. Some, like CoolTalk and NetMeeting, come bundled with popular Web browsers. Others are stand-alone products. Internet telephony products are sometimes called IP telephony, Voice over the Internet (VOI) or Voice over IP (VOIP) products.


VOIP SOFTWARE EXAMPLES

Skype TeamSpeak

12VoIP Yahoo! Messenger

internet

Technology

uniform resource locator

world wide web

text link

administrative autonomy

itec 1010 information

web page

home page

www