CSM 184: Comprehensive Notes on the Internet and Worldwide Web

Definition and Current State of the Internet

• Historically, the Internet was characterized as a network of networks that joined government, university, and private computers together. It provided the necessary infrastructure for using e-mail, file archives, bulletin boards, hypertext documents, databases, and various other computational resources.

• It serves as a vast collection of computer networks acting as a single huge network to transport data and messages across any distance, ranging from a single office to global locations.

• In its current state, the Internet is a worldwide telecommunications system providing connectivity for millions of smaller networks. It is a worldwide collection of networks linking millions of businesses, government agencies, educational institutions, and individuals.

• The system allows computer users to communicate regardless of physical distance or the specific computer platforms being utilized.

Historical Development and Evolution of the Internet

• The origin of the Internet dates back to $1969$ as a project for the U.S. Department of Defense's Advanced Research Project Agency (ARPA). The primary motivation was to ensure immediate communication within the Department in the event of war.

• Initial computer installations occurred at U.S. universities involved in defense-related projects. As scholars began using the system, the network's focus shifted from military applications to scientific use.

• As the ARPAnet grew, system administration became distributed across organizations such as the National Science Foundation (NSF).

• The transition from a science-oriented ARPAnet into the commercially minded Internet involved a shift in responsibility and funding, leading to the system used by millions today.

• Key Milestones in the Evolution of the Internet:

  • $1969$: ARPANET becomes functional with two main goals: to allow scientists at different locations to share information/work together, and to remain functional even if part of the network is destroyed by a disaster.

  • $1984$: ARPANET links more than $1,000$ individual computers as hosts.

  • $1986$: NSF connects NSFnet to ARPANET, at which point the system becomes known as the Internet.

  • $1995$: NSFNet terminates its status as a network on the Internet and resumes its role as a dedicated research network.

  • $1996$: Internet2 is founded.

  • Today: More than $550$ million hosts connect to the Internet.

Internet Infrastructure and Network Management

• The Internet functions as a pipeline to transport electronic messages Between networks.

• At the core of most networks is a server, which is a fast computer equipped with large amounts of memory and storage space. The server controls information communication between attached devices, including computers, printers, and other servers.

• Each individual organization is responsible only for the maintenance of its own specific network.

• The World Wide Web Consortium (W3C) is the body that oversees research and establishes guidelines and standards for the Internet.

Domain Name System and Addressing

• An IP address is a specific number that uniquely identifies every computer or device connected to the Internet.

• A domain name serves as the text-based version of an IP address (e.g., apps.knust.edu.gh).

• A DNS server performs the task of translating a domain name into its corresponding numerical IP address.

• Components of a Domain Name:

  • The first field is the host name, which identifies the organization or a single computer.

  • The last field is the Top-Level Domain (TLD), which describes the organization type or the country of origin.

• Specific Generic Top-Level Domains and their intended purposes:

  • .aero: Aviation community members.

  • .biz: Businesses of all sizes.

  • .cat: Catalan cultural community.

  • .com: Commercial organizations, businesses, and companies.

  • .coop: Business cooperatives like credit unions.

  • .edu: Educational institutions.

  • .gov: Government agencies.

  • .info: Individuals or organizations providing general information.

  • .jobs: Employment or human resource businesses.

  • .mil: Military organizations.

  • .mobi: Delivery and management of mobile Internet services.

  • .museum: Accredited museums.

  • .name: Individuals or families.

  • .net: Network providers or commercial companies.

  • .org: Nonprofit organizations.

  • .pro: Certified professionals (doctors, lawyers, accountants).

  • .tel: Internet communications.

  • .travel: Travel industry.

Web 2.0: The Interaction Shift

• Web 2.0 describes the current state of the web, emphasizing user-generated content and high usability for end-users compared to the earlier Web 1.0.

• It refers to websites that provide various means for users to interact with one another.

• Unlike a software update, Web 2.0 does not refer to specific technical upgrades but rather a fundamental shift in how the Internet is used to promote information sharing and interconnectedness.

The World Wide Web Interaction Process

• The process of accessing the web follows a specific sequence:

  • Step 1: Start the Web browser by clicking its taskbar icon or typing the name in the search box on the Start menu.

  • Step 2: The browser checks its home page settings (e.g., msn.com).

  • Step 3: The browser communicates with a server maintained by the Internet access provider. This server translates the domain name to an IP address (e.g., $207.68.172.234$) and sends that IP back to the computer.

  • Step 4: The browser uses that IP address to contact the specific Web server associated with the home page and requests the data. The Web server then sends the home page back to the computer.

• Tabbed browsing is a feature that allows users to view multiple Web pages within a single browser window simultaneously.

Advanced Search and Content Evaluation

• Search operators help refine results:

  • Exclude a word: Use a minus sign (e.g., automobile -convertible excluding results about convertibles).

  • Exact phrase: Use quotation marks (e.g., "19th century literature").

  • Wildcard character: Use an asterisk to substitute characters (e.g., writer* to find writer, writers, or writer's).

• Evaluating Web information for accuracy is essential because no single entity oversees Web page content. Criteria for evaluation include:

  • Audience: Is the site written at an appropriate level?

  • Authority: Does the site list an author and their credentials?

  • Content: Is the site well-organized with working links?

  • Currency: Is the information current or out of date?

  • Design: Does the page download quickly? Is it visually pleasing and easy to navigate?

  • Objectivity: Is the site free of preconceptions and excessive advertising?

Multimedia and Browser Extensions

• Multimedia refers to applications combining text with graphics, animation, audio, video, or virtual reality.

• A graphic is a digital representation of non-textual information. Common formats include:

  • BMP: Bitmap Image file.

  • GIF: Graphics Interchange Format.

  • JPEG: Joint Photographic Experts Group.

  • PNG: Portable Network Graphics Format.

  • TIFF: Tagged Image File Format.

• A thumbnail is a reduced-size version of a larger graphic.

• A plug-in (also known as an extension or add-on) is a program that extends the capabilities of a web browser.

• Plug-ins are distributed via unique webstores:

  • Microsoft Edge: https://microsoftedge.microsoft.com/

  • Google Chrome: https://chrome.google.com/webstore

  • Opera: https://addons.opera.com

  • Mozilla Firefox: https://addons.mozilla.org/

• Popular and Useful Plug-ins:

  • Lastpass: Password manager for creation and storage.

  • Pocket: Saves articles and websites for later viewing.

  • Grammarly: Real-time spelling and grammar checking.

  • Honey: Applies coupons during online shopping.

  • Adblock: Prevents intrusive popups and ads.

  • Evernote: Enables note-taking while browsing.

Internet2

• Internet2 is an academic-only system involving partnerships between universities, industry, and government.

• The goal is to conduct research into high-bandwidth applications, such as remote access to telescopes or medical diagnostic devices.

• A current research example includes remote surgery, where robot hands mimic the movements of a distant surgeon who monitors the patient via video.

Netiquette and Global Online Ethics

• Netiquette is the code of acceptable behavior on the Internet. The Golden Rule is to treat others as you would like to be treated.

• Guidelines for E-mail, Chat, and Newsgroups:

  • Keep messages brief and use proper grammar, spelling, and punctuation.

  • Be cautious with humor and sarcasm as they can be misinterpreted.

  • Avoid offensive language and shouting (using ALL CAPITAL LETTERS).

  • Read messages before sending and use meaningful subject lines.

  • Avoid flames (insulting messages) and flame wars (exchanges of flames).

  • Do not send spam (unsolicited e-mail sent to many recipients).

  • Clearly identify spoilers (information revealing game solutions or movie endings).

• Common Emoticons:

  • :) - Smile

  • :( - Frown

  • |: - Indifference

  • :\ - Undecided

  • :O - Surprised

• Common Acronyms:

  • btw: by the way

  • imho: in my humble opinion

  • fyi: for your information

  • ttfn: ta ta for now

  • fwiw: for what it's worth

  • tyvm: thank you very much

Cybersecurity and Personal Data Protection

• Identity theft can happen to anyone if personal information (name, social security number, account numbers) is compromised.

• Verify how information will be used before sharing it and check for indicators that a website is secure before banking or shopping.

• Phishing involves email or pop-up messages from entities claiming to be your bank, ISP, or government agency, urging you to validate account information on a bogus website. Legitimate businesses do not ask for personal info via email.

• Password Security Best Practices:

  • Passwords should be over $8$ characters long.

  • Combine letters, numbers, and symbols.

  • Avoid using common words, names, birthdays, or locations.

  • Change passwords every $90$ days.

  • Use different passwords for every account.

Navigation and Tracking: Bookmarks and Cookies

• Bookmarking is the act of saving a web page shortcut for later reference. In most browsers, this is done by clicking the star icon in the address bar or using the keyboard shortcut Ctrl + D.

• HTTP Cookies are small text files created during browsing that capture data about patterns. These are stored on the device and used by websites to tailor the browsing experience.

• Three Categories of Cookies:

  • Session Cookies: Temporary; expire when the browser or page is closed. These are often essential for site functioning and created without user consent.

  • Persistent Cookies: Store user settings and credentials; expire on a specific date set by the server. These require user consent.

  • Third-Party Cookies: Created by websites other than the one currently being visited to track activities and push advertisements. These require user consent.

• Advantages of Cookies: Personalized browsing, session tracking, improved site performance, site analytics, and targeted advertising.

• Disadvantages of Cookies: Privacy concerns, security risks, inaccurate data tracking, cumbersome consent management, and being tied to a single specific device.

• Clearing cookies can be done via browser settings under "Privacy" or "Privacy & Security" by selecting "Clear browsing data."