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The Internet (Discovering Computers & Microsoft Office 2010pages 8-10, 44-94, IE2-IE10) One or more stand-alone computers would not be considered a network environment – why? Stand-Alone PC When computers communicate with each other then you have a network Communications Protocols determines the rules for communicating between PCs. PC gets files from server Processing is done on the Client PC stores files on server File Server PC PC Client Local Area Network A typical local area network has clients communicating with a server PC Client PC Client PC Client File Server PC Client PC Client Local Area Network You can expand the communications environment by creating an Internetwork – a LAN connected to a LAN PC Client PC Client PC Client PC Client PC Client Router or Switch File Server PC Client PC Client PC Client File Server PC Client InterNetwork PC Client What is the Internet? A network of networks interconnected throughout the world The Internet involves other components, but in essence is just a large network Governmental Institution (.gov) PC Client PC Client To other cities all over the world To other cities all over the world PC Client Chicago File Server PC Client PC Client PC Client PC Client PC Client PC Client Communications Protocol -- TCP/IP PC Client PC Client File Server PC Client File Server Houston PC Client Internet Service Provider or ISP (.net) Educational Institution (.edu) The Internet PC Client New York PC Client Commercial Bussiness (.com) Home PC Home PC Home PC Typical path to the Internet Who created it? In 1969, the Internet began as a department of defense project called ARPANet (four computers in California and Utah) Vincent Cerf & Robert Kahn are generally acknowledged as the fathers of the “Internet”. In 1985 University professors (the original nerds) expanded the concept into a research tool to share information with professors across the nation – This was the creation of the NSF network The World Wide Web was created by a British scientist named Tim Berners-Lee in the early 1990s. The WWW provides the GUI for the Internet. Utilization of the WWW led to the popularity explosion of the Internet Internet Hosts A Host on the Internet is a computer that contains data that may be accessed by users anywhere in the world The Internet began with 4 hosts in the 1960’s and today numbers over 550 million The Internet “backbone” is comparable to major interstate highways running throughout the nation. Internet traffic flows through the backbone Most backbones are maintained by “AT & T”, “SBC”, “MCI”, “Sprint”, and others. These companies are known as “Network Service Providers” (NSPs) What do I need to get on the Internet? A computer Internet Connection: A modem / telephone line (dial-up – slow, if you have this at home you’re probably still waiting for Quiz 1 to download ) Fiber to the Premises (FTTP) – uses fiber optic cable to provide high-speed Internet access to home and business users Fixed Wireless – high speed Internet connection via radio signals using antennas & towers Satellite – when cable hookup is not available - farthest range but not as fast as other connections and subject to interference in the atmosphere Modem – TV cable line – typical speed 6 – 30 Mbps. Referred to as an “Always On” broadband connection Wi-Fi (wireless fidelity) – Uses radio signals to provide wireless access to computers and devices Cellular radio network – offers high-speed Internet connection to devices with built-in compatible technology Cable ISP - Internet Service Provider - a company that provides access to the Internet through their equipment (monthly fee required – National, regional, or local) OSP – Online service provider – provide extra services for members, example: AOL, MSN A Browser - software that allows a user to navigate through the Internet What Can I Do on the Internet? Broadcasting – viewing video teleconferences as well as listening to radio shows (webcasts). Podcasts are popular today Internet Telephony – free “telephone like” conversations (Voice over IP - VoIP) Send electronic correspondence (E-mail web or client based) Advertise Research information using Gopher (non-graphical) or the WWW Converse with other users in “Chat Rooms” / Instant Messaging (IM) is a variation of the traditional chat E-commerce – Shop on the Internet – ensure the VeriSign seal displays to increase the probability of a secure transaction FTP – Download and Upload files Create Blogs – Internet personal journal / Micro-Blogs shorter version, like Twitter WIKIS – Like a blog but can be edited by any user Internet Terminology Protocol TCP/IP Domain Name Hypertext Link HTTP E-Mail IP Address URL Web Page Cookie HTML bps Webmaster Plug-Ins WI-FI HotSpots Tabbed Browsing Definitions Protocol- The rules & guidelines computers must follow to exchange information on the Internet or on a network. Several Internet protocols must be present TCP/IP (Transport Control/ Internet Protocol)- the language spoken between computers on the Internet. All data has to be in TCPIP format Top Level Domain (TLD)- The address mechanism used on the internet to identify a server. Kind of like a file extension. ex., .edu, .com, .mil, .gov, .biz Hypertext- A cross-reference web software feature that helps the user transfer to a web page at another site. Links are created to allow the user to move (or link) easily from one document to another Link- An underlined reference within a web page that when clicked upon, transfers a user to another web page or site. E-Mail- A system that lets computer users exchange messages with other computer users electronically. The messages go to an email server instead of directly to the end recipient. The recipient must then retrieve the mail from the server. IP Address - Most Internet hosts or servers use “static” IP addresses. Most other computers use a temporarily assigned IP address referred to as a “dynamic” IP address. The IP address identifies a device while on the Internet. Without one, you can’t get on the Internet. Dynamic IP addresses are provided by your ISP Web page - contains information on a particular topic or location and often provides links to other pages URL (Uniform Resource Locator)- Address of an individual web page – no blank spaces in a URL HTTP (Hypertext Transport Protocol)- A protocol used to transfer hypertext documents between computers on the WEB. Cookie - File installed on a user’s hard drive by a web site to remember a user’s preferences and settings HTML - Hypertext markup language is a code used to develop web pages. Today web authoring software such as “FrontPage” and “homepage” makes web page development fairly simple bps - The speed at which information is transferred between computers is measured in bits. Common bit units are kilobits and megabits Webmaster - Person who maintains or develops web sites Plug-Ins – free “helper applications” or “add-ons” that assist a browser in performing some type of task – Shockwave and Flash are examples WI-FI HotSpot – an area in which the public can access a wireless connection to the Internet, usually for free Tabbed Browsing – easier to keep track of your browsing sites during your session. Supported by most current or new browsers This is a sample of a Web Page URL Links Internet Interfaces - Browsers MOSAIC – 1st graphical browser - created my Marc Andreessen Microsoft Internet Explorer - (IE) most popular (first appeared for free in Windows 95) Lynx (non-graphical) Opera – developed in Norway in 1996, an alternative to IE and Firefox Mozilla Firefox – Ranks #2 behind only Internet Explorer / “Camino” is the “Mac” version Safari – popular on the “Mac” Others – check the Internet Google Chrome What Internet tools allow me to search for information? SEARCH ENGINES! - Search engines are like the yellow pages in the phone book where you can look up a topic or category and obtain the addresses to web sites – some search engines also include “Subject Directories” which enhance the experience (see your book) / Boolean operators such as “AND” & “OR” enhance & refine the search AltaVista Yahoo – also features “AlltheWeb.com” Lycos Web Crawler Excite Google Dogpile Ask Internet II A separate “high speed” Internet for “select” universities, industry, and the U.S. military Commercial free Primarily for research Web 2.0 New wave of web-based services emphasizing online collaboration and sharing – it’s happening now / Web 3.0 (Semantic web) is on the way The World Wide Web Consortium (W3C) Over 350 Organizations from around the world oversee research and set standards and guidelines for many areas of the Internet Security & Ethical Issues on the Internet Pornography - not how to find it but how to censor it from minors Hazards / Malware - guarding against viruses, spy ware and unauthorized access Crime - stalking, theft, hate propaganda, sabotage Logos, Patents and Copyrights - other users may steal your ideas – little protection Communications infrastructure – Bandwidth. Telephone lines were not intended for Internet traffic, current equipment is too slow CDA - Censorship through the “computer decency act”. Can lawmakers go too far and control what we can and cannot do on the Internet? THE END -Happy Surfing-