02 - The Internet and www cyberspace_f101b5b86ca93cc7da54e01cfd761459

1. Introduction to the Internet and the World Wide Web

  • Author: Williams, B.K, Stacy C. Sawyer

  • Title: Using Information Technology: A Practical Introduction to Computers & Communications

  • Edition: Seventh Edition, McGraw-Hill

  • ISBN: 978-0-07-110768-6

2. Outline of Material

  • Connecting to the Internet

  • How Does the Internet Work?

  • The World Wide Web

  • Email & Other Ways of Communicating over the Net

  • Telephony, Multimedia, Webcasting, Blogs, E-Commerce

  • Security Concerns: Snooping, Spoofing, Phishing, Pharming, Cookies, & Spyware

3. Connecting to the Internet

3.1 Internet History

  • 1969: ARPANET initiated by the US Department of Defense.

  • Growth: 62 computers in 1974, expanded to 500 in 1983, and 28,000 by 1987.

  • Multimedia: Became available on the internet in early 1990s.

3.2 Requirements for Connection

  • Access Device: Computer

  • Connection Method: Phone line, cable, or wireless.

  • Internet Service Provider (ISP): Essential for access.

3.3 Bandwidth Definitions

  • Bandwidth: Amount of data transmitted in a given time.

  • Baseband: Allows only one signal transmission at a time.

  • Broadband: Supports multiple signals simultaneously.

3.4 Data Transmission Speeds

  • Measured in bits per second (bps).

  • Conversions:

    • 8 bits = 1 character

    • 28.8 Kbps modem = 3600 characters per second.

  • Speeds: Kbps, Mbps (1 million bps), Gbps (1 billion bps).

3.5 Modem Types

  • Internals/External: Connects to ISPs.

  • Types of Lines: High-speed phone lines, Satellite, Cable, Wi-Fi, and 3G.

3.6 Special Connection Types

  • ISDN: 64-128 Kbps over copper lines.

  • DSL: 1.5-9 Mbps, always-on.

  • Cable Modems: Connect PCs to cable-TV systems.

  • Wi-Fi & 3G: Wireless standards and connectivity.

4. How Does the Internet Work?

4.1 Internet Access Providers

  • Types:

    • ISPs: Local to global service.

    • Commercial Online Services: Example includes AOL.

    • Wireless ISP: Mobile connectivity.

4.2 Network Structure

  • Thousands of interconnected networks including education, commercial, nonprofit, and military.

  • Client/Server Model:

    • Client: Requests data.

    • Server: Supplies data.

4.3 Points of Access

  • Point of Presence (POP): Local access to an ISP.

  • Network Access Point (NAP): Routing points with several connections.

    • Major NAPs established in 1993.

4.4 Internet Backbone

  • High-capacity lines using leading technology for data transmission.

  • Internet 2: Cooperative research for higher-speed data.

4.5 Protocols and Addressing

  • TCP/IP: Core internet protocol.

  • IP Addresses: Unique identifiers for devices.

    • Static vs. Dynamic addresses.

4.6 Internet Governance

  • ISOC, ICANN, and ARIN: Organizations overseeing standards and registration.

5. The World Wide Web

5.1 Browsers and Websites

  • Browsers: Software to surf the web (e.g., Internet Explorer, Firefox).

  • Web Pages: Unique documents including images, videos, and links.

  • Uniform Resource Locator (URL): The address for web resources.

5.2 Domain Names and Structure

  • Unique identifications; .gov for government, .org for non-profits.

  • Typographical errors can lead to unintentional navigation to harmful sites.

5.3 Web Technologies

  • HTTP/HTTPS: Protocols for web access; secure version for transactions.

  • HTML: Markup language for web page structure.

5.4 Navigation

  • Home Page: Primary page of a website.

  • History Lists & Bookmarks: Tools for returning to visited pages.

5.5 Web Portals and Search Services

  • Portals: Gateway websites offering various services (e.g., Yahoo, Google).

  • Search Engines: Software for finding information via keywords.

6. Email & Communication Methods

6.1 Email Programs

  • Software for sending and receiving emails (e.g., Outlook, Eudora).

  • Web-based Email: Access emails through a browser (e.g., Gmail).

6.2 Features of Using Email

  • Format of sending emails, using attachments, and email address management.

6.3 Other Communication Methods

  • Instant Messaging: Real-time message exchange.

  • FTP: Transfer Protocol for files between different OSs.

  • Newsgroups and Listserv: Group discussion platforms.

7. Online Safety

7.1 Security Issues

  • Snooping: Lack of email privacy.

  • Spam: Unwanted messages often containing threats.

  • Spoofing and Phishing: Deceptive practices to extract personal information.

    • Always verify source before responding.

7.2 Malicious Techniques

  • Pharming: Redirecting users to false sites.

  • Cookies: Data files storing personal information; can be used for tracking.

  • Spyware: Programs collecting data secretly.

7.3 Prevention Strategies

  • Use anti-spyware tools and be cautious with downloads.

  • Always read terms before agreement during installations.