The Internet & World Wide Web

The Internet & the World Wide Web: Exploring Cyberspace

• The Internet started in 1969 as ARPANET
• Multimedia became available on the Internet in the early 1990s, marking the birth of the World Wide Web

Connecting to the Internet

• An access device, a means of connection, and an Internet access provider is needed.

Bandwidth

• Bandwidth expresses how much data can be sent through a communications channel in a given amount of time
• Baseband is a slower connection type allowing only one signal to be transmitted at a time.
• Broadband provides high-speed connections.

Physical Connections

• Physical connections to the Internet can be wired or wireless
• Wired connections include telephone [dial-up] modems and high-speed phone lines (DSL, T1/T3) and cable modems
• Wireless connections include satellite and other through-the-air links.

Data Transmission Speeds

• Data transmission speeds was originally measured in bits per second (bps)
• 8 bits are needed to send one character
• Kbps connections send 1 thousand bits per second
• Mbps connections send 1 million bits per second
• Gbps connections send 1 billion bits per second
• Uploading transmits data from a local to a remote computer
• Downloading transmits data from a remote to a local computer

Narrowband (Dial-Up Modem)

• A narrowband connection is low speed but inexpensive
• Telephone lines are narrowband and have low bandwidth
• A dial-up connection uses a telephone modem to connect to the Internet, mainly in rural areas using POTS (plain old telephone system)
• Telephone modems can be internal or external with a maximum speed of 56 Kbps
• Most ISPs provide local access numbers

High-Speed Phone Lines

• High-speed phone lines are more expensive but available in most cities & towns
• DSL lines use regular phone lines and DSL modems and receive data at 7–105Mbps, sending at about 384 Kbps – 1 Mbps.
• DSL lines always on and need to be within 4.5 miles of the phone company switching office and are not always available in rural areas
• T1 lines are very expensive traditional trunk lines (fiber optic or copper) that carry 24 normal telephone circuits with a transmission rate of 1.5 – 6 Mbps. (T3 = 6 – 47 Mbps)
• T1 lines "last mile" can still be a problem and are generally used by large organizations.

Cable Modems

• TV cable systems with Internet connections; company usually supplies cable modems
• Cable modems are always on and receives data at up to 100 Mbps; sends at about 2-8 Mbps

Satellite Wireless Connections

• Satellite Wireless Connections transmit data between a satellite dish and a satellite orbiting Earth
• The connection is always on and requires an Internet access provider with 2-way satellite transmission with ability for the user to buy or lease the satellite dish and modem.

Other Wireless

• Wi-Fi stands for “wireless fidelity" and is a name for a set of wireless standards (802.11) set by IEEE
• A Wi-FI connection transmits data wirelessly up to 54 Mbps for 300-500 feet from an access point (hotspot) and is typically used with laptops and tablets with Wi-Fi hardware
• 3G is "third generation", uses existing cellphone system, handles voice, email, and multimedia
• 4G is "fourth generation" and is faster than 3G, built specifically for Internet traffic (but not standard yet)
• Both 3G and 4G are used mostly in smartphones.

Internet Access Providers (ISPs)

• ISPs are local, regional, or national organization providing Internet access for a fee
• Wireless Internet Service Providers (WISPs) enables wireless-equipped laptop/tablet and smartphone users to access the Internet

How the Internet Works

• The Internet is a huge network connecting hundreds of thousands of smaller networks
• Client/server networks are central to this arrangement, with the client being a computer requesting data or services, and the server being the central computer supplying the data or services requested.

Internet Connections

• Point of Presence (POP) is a collection of modems and equipment in a local area that acts as a local gateway (access) to an ISP's network
• ISP connects to an Internet Exchange Point (IXP)
• Internet Exchange Point (IXP) is a routing computer at a point on the Internet where several connections come together
• IXPs are run by private companies
• IXPs allow different ISPs to exchange Internet traffic.

Internet Backbone

• Internet Backbone is high-speed, high-capacity data transmission lines (fiber optic) that uses the newest technology
• AT&T, Sprint, Verizon, CenturyLink, and Deutsche Telekom are all backbone providers
• Internet 2 is a cooperative university/business education and research project that adds new “toll lanes” to older Internet to speed things up and advance videoconferencing, research, collaboration.

Internet Communications

• Connecting to an ISP's point of presence (POP) involves handshaking to establish the fastest transmission speed and authentication through correct password & username
• Protocols are rules a computer follows to electronically transmit data
• TCP/IP (Transmission Control Protocol/Internet Protocol) is the Internet protocol, which was developed in 1978 by ARPA and used for all Internet transactions
• Packets are fixed-length blocks of data for transmission, determined by TCP/IP with transmissions broken up into packets and re-assembled at destination

IP Addresses

• Every device connected to the Internet has an address
• IP addresses uniquely identify each device and are four sets of numbers separated by periods. Each number is between 0 and 255
• Dynamic IP addresses can change with every use
• Individual computer users are assigned static IP addresses when they log on
• Static IP addresses don't change and are used by established organizations (ISPs) and companies that pay for them.

Internet Governance

• No one owns the Internet
• The Internet Society (ISOC) board of trustees oversees standards
• The Internet Corporation for Assigned Names and Numbers (ICANN) regulates domain names (such as .com, edu., .net) that underlie IP addresses without controling content.

The World Wide Web

• The World Wide Web brought multimedia to the Internet
• The web and the Internet are not the same; the web is multimedia-based, unlike the Internet
• The Internet is the infrastructure that supports the web
• A browser is software that gets the user to websites and their individual web pages and displays the content similarly regardless of the computer, operating system, and display monitor
• Examples of browsers are Internet Explorer, Mozilla FireFox, Apple Macintosh's Safari, Google's Chrome, and Microsoft's Bing.

Website

• Website are located on a particular computer (server) with a unique address
• Can include text, pictures, sound, and video
• www.barnesandnoble.com, www.mcgraw-hill.com, are examples
• Any website that hosts the server could be located anywhere
• First page on a website is the Home page and contains links to other pages

Uniform Resource Locator (URL)

• Describes the address for a web page and is a character string pointing to specific information
• Consists of the web protocol, the domain name, web server, directory name, the folder and the file within the directory
• Can contain an optional extension

Web Nuts and Bolts

• TCP/IP: general Internet Protocol
• HTTP-Protocol Used to Access World Wide Web
• Hypertext Markup Language (HTML): the markup language used in writing and publishing web pages, which contains instructions to specify formatting and links to other documents on the web
• Hypertext links connect one web document to another
• Tim Berners-Lee saw the possibility of using hyperlinks to link any information over the Internet.

Using web browser

• Web browsers interpret HTML and allow you to move around the Internet and web
• Web browsers comes preinstalled on most PCs, but can be downloaded
• Browsers come with five basic elements: URL (address) bar, menu bar, toolbar, workspace, and status bar
• The page you see when you open your web browser is called the Home Page, which you can customize anytime you want
• The browser uses icons to move from one page to another

Navigation

• Every browser comes with an easy to use navigation menu
• History List: list of websites you visited since you opened up your browser
• Bookmark stores the URL and returns you to the particular site

Web Page Interactivity

• Clicking hyperlinks transfers you to another page, and radio buttons choose an option
• Text can be typed into text box and is executed by "enter"
• Scroll arrows move you up and down, and side to side
• Different frames separates controllable sections of a web page

Web portals

• Web portals: Starting points for finding information
• The doorway website offering broad array of resources and services that require log in
• Examples of Portals are Yahoo!, Google, Bing, Lycos, and AOL
• Subject guide find topics and use keywords to search them

Search Engines

• Organizations maintain searchable databases to access information using portals like Yahoo!, Bing, Google, Ask.com, Gigablast
• Search Engines are programs to search questions and keywords
• Databases are made using software spiders, crawler, bots, agents, indexing the words on that site

Search Engine Types

• Individual search engines have their databases from web and their examples are Ask, Bing, Google, and Yahoo!
• Subject directories are created by human editors
• Metasearch Allows you to simultaneously search several search engines like Yippy!, Dogpile, Mamma, MetaCrawler, and Webcrawler
• Specialized Search Engines search for specialized subject matter like movies, health, jobs e.g. Career.com. WebMD, Expedia, and U.S. Census Bureau

Search Strategies

• If you're just browsing, try a subject directory; then try a metasearch engine
• If you're looking for specific information, try Answers.com “one-click" search or go to general search engine, then a specialized one or a subject
• If you're looking for everything on a subject, try the a search on several search engines

Wikis & Wikipedia

• A wiki is downloadable website that's easy to correct and add to
• Wikipedia is free to edit and contribute to. It's not considered reliable by librarians

Multimedia Search Tools

• Tools to search and locate media on web
• Still images: Google Image Search, Bing Images, and Fagan Finder
• Audio: Yahoo! Music and Lycos MP3 Search
• Video: AlltheWeb and AOL.video
• Scholarly: Google Scholar

Tagging

• Do-it-yourself labels for Internet content that can't be easily shared
• The tags can be used on blogs and YouTube that are keywords used to classify content
• Tagging is available through delicious.com and BlinkList

Email Basics

• Outgoing mail gets sent to a Simple Mail Transfer Protocol (SMTP) server
• Incoming mail uses Post Office Protocol version 3 (POP3)

Email Functions

• Email programs (Outlook) and web-based (Gmail) are used to send and receive mail
• Program versions are interacted through email software on a computer to interact with a server
• Web-Based interact via browser
• Two-way send and receive allows traveling while equipped with mobile device and computers as well

Email addresses

• User name, domain, and type are standard format

Email Programs Tips

• Address-book store emails, folders, attachments are aware of netiquette

Email Safety

• Attachments are copies of files that must have compatible software to read
• Files can carry viruses that must have antivirus software installed

Digital Netiquette

• Be timely, write with personality, and be clear
• Avoid jokes and sloppiness with required documentation

Instant Messaging

• IM enables email with a specified user in real time with downloads
• Email systems allow this messaging with downloading
• Available on AOL/AIM, GoogleChat, Windows Messenger, and Yahoo Messenger

Discussion Software

• Lists for subscribing and discussion are email messages to specific groups, topics, and addresses
• Electronic bulletin boards participate through news reader software
• Messages can be accessed through browsers and called software

File Transfer Protocol

• Download large files between different computers using browser or the available programs

Telephony

• Internet telephone makes calls (long-distance) using software, Internet connect, speakers, and microphones

Multimedia Web

• images, sound, video and animation are used with plug-ins
• Java small programs and variety exist

Web Automatically Comes to You

• Push technology can download info to computers
• Use webcasting with text, Video, and audio with RSS scour

Blogs and Podcasting

• Web logs are easily viewed with radio or device

E-Commerce

• Doing business online in multiple rival locations at a low price
• B2B being business
• B2C being to consumer, and C2C sales or auctions for services

Web 2.0

• interactive experience on web in forms of blogs, and networking

Social Networking

• Networking sites are online communities to interact with the world
• Sharing sites include picture, media, or music and aggregators help track friends

Web 3.0

• Computer generated information with markup and personal interaction

Online Danger

• Email is not private with friends, management, and providers with hard disks
• Unsolicited email can be avoided with filters with sites set on safety modes

Email Danger

• Using fake identities and emails can be avoided
• Direct recipients to fake websites or steal important data
• URL sites that appear like you typed do not install the correct malware with spyware

Phishing Danger

• Don't click the links

Cookies

• Leave file text and browsing information on systems, including, Log-in, credit, and name
• Websites notice and track activity through tracking habits

Spyware and Adware

• Sneak software that comes through ads and transfers without consent through malware
• Hijack setting, change webpages, and run searches or install keystrokes
• These methods steal vital information