Worksheet: Internet and Web

A computer network is defined as an interconnection of two or more computers that allows them to share resources and communicate. Networks play a crucial role in daily life by enabling information exchange, communication through emails and instant messaging, and resource sharing like printers and internet access. For instance, in a workplace, a network allows employees to collaborate effectively by sharing documents and applications.

LAN (Local Area Network) connects computers within a limited area, like a home or office, typically covering distances up to 1 km. Examples include home Wi-Fi networks. MAN (Metropolitan Area Network) spans a city or town, connecting multiple LANs; an example would be a city's cable TV network. WAN (Wide Area Network) covers broad geographical areas, connecting LANs and MANs globally; the Internet is the largest WAN. Each type of network serves different needs based on scale and geography.

A modem, short for Modulator-Demodulator, is an important device in computer networks that converts digital data from a computer into analog signals for transmission over telephone lines and vice versa. Its function includes modulation at the sending end, which converts digital signals to analog, and demodulation at the receiving end, which converts them back to digital. This enables computers to connect to the Internet via broadband or dial-up connections, allowing access to online resources and communication.

A switch is a networking device that connects devices within a LAN and uses MAC addresses to forward data only to the intended device, making it efficient in managing data traffic. It allows multiple devices to communicate simultaneously without collision. A router, on the other hand, connects different networks, such as a LAN to the Internet, and uses IP addresses to route data. It analyzes incoming data packets and determines the best path for the information, enabling communication across varied networks.

The World Wide Web, commonly referred to as the Web, is a system of interlinked hypertext documents accessed via the Internet. Key components include HTML (HyperText Markup Language), which structures web pages; URLs (Uniform Resource Locators) that provide addresses for these pages; and HTTP (HyperText Transfer Protocol), which governs the transfer of data on the Web. Together, they enable users to access and share vast information online efficiently.

A web page is a document available on the World Wide Web, typically created using HTML and viewed in a web browser. Static web pages display the same content to every user and do not change without manual updates. They are simple and faster to load. In contrast, dynamic web pages can change content based on user interactions or data retrieved from servers. They are generated in real-time, making them more complex but allowing personalized experiences, such as user dashboards or e-commerce sites.

Hosting a website involves several steps: First, select a web hosting service provider that meets your needs, considering factors like storage and bandwidth. Next, choose and register a domain name that represents your site. After securing web space, organize and upload website files (HTML, CSS, etc.) to the server. The domain name must be linked to the server's IP address via the Domain Name System (DNS) to make the website accessible online.

Cookies are small text files stored by the browser on a user's device, containing information about the user's browsing sessions. They enhance user experience by remembering login details, personal preferences, and shopping cart items. Cookies can also be used for tracking user behavior for analytics and targeted advertising. While beneficial, they raise privacy concerns; hence browsing settings allow users to manage cookie permissions.

A web browser is a software application that retrieves and displays web content, enabling users to navigate the Internet. Key functions include rendering HTML documents, managing bookmarks, and executing script files (like JavaScript) for interactive features. Browsers also enhance security through features like pop-up blockers and privacy settings. They are essential for accessing the vast resources of the web, making it user-friendly and interactive.

LAN connects devices within a small area like a home or office, offering high speeds and low costs. MAN links LANs across a city, providing moderate speeds and higher costs. WAN connects devices over larger geographical areas, such as countries, with lower speeds and greater costs. Applications: LAN for local communication, MAN for city-wide services, WAN for global connectivity. Limitations include range and speed constraints for LAN and MAN, and high costs for setup and maintenance in WANs.

Routers connect different networks, directing data packets based on IP addresses, while switches operate within a single network, forwarding data to specific devices based on MAC addresses. Routers manage traffic between networks and provide security, while switches enhance efficiency in a local network.

Static web pages display the same content to every user and are coded in HTML only, while dynamic pages can change content based on user inputs or database interactions, often using languages like PHP or JavaScript. Static pages are simpler and quicker to load; dynamic pages require server-side processing, enhancing interactivity.

Voice over Internet Protocol (VoIP) allows voice communication over the Internet. Advantages include cost-effectiveness and mobility; calls can be made from any Internet-enabled device. Drawbacks involve dependency on Internet connection quality, where poor connectivity can degrade call quality.

To host a website, choose a hosting provider and register a domain name. Upload website files to the host server and map the domain name to the server's IP address. Finally, configure DNS settings to ensure users can reach the site using the domain name.

Servers provide resources and services to clients that request them. Clients initiate requests, whereas servers respond to those requests, processing data according to client needs. The interaction defines a client-server model fundamental to internet functioning.

The internet is a global WAN consisting of interconnected routers, servers, and various networking technologies. Factors include redundant data paths, multiple protocols for addressing and routing, and robust infrastructure capable of adapting to loads and failures.

Cookies are small data files stored by browsers to remember user preferences, login states, and activity across sessions. They enhance user experience by personalizing content; however, they also raise privacy concerns regarding tracking and data sharing without user consent.

A URL consists of the protocol (http or https), domain name, path, and optional parameters. The protocol indicates how data should be transmitted; the domain specifies the site location; the path indicates specific resources, and parameters can pass additional settings to a webpage.

Modern browsers support advanced features, including JavaScript execution for dynamic content, CSS for styling, and plug-ins for enhanced capabilities. They enable smoother navigation and interactive elements on web pages, greatly improving the user experience.

Examine how internet access enhances educational opportunities but also explore issues such as digital divide and content quality.

Discuss how the choice of topology can affect performance, costs, and scalability of a network. Provide examples.

Explore features like privacy settings, extensions, and user interface while mentioning potential drawbacks like security vulnerabilities.

Identify specific security protocols involved in VoIP and discuss possible security breaches and their implications.

Analyze how each type of web page affects user interaction, site maintenance, and SEO.

Examine energy consumption, cooling systems, and waste, then propose alternatives or improvements to enhance sustainability.

Discuss how cookies personalize services while highlighting user privacy issues and potential risks.

Analyze the interaction between digital platforms and real-world advocacy, including successes and challenges.

Discuss the balance between freedom of speech and the responsibility to prevent harm. Provide examples.

Evaluate improvements in connectivity and potential issues like infrastructure costs and health concerns.