Question 1: Describe in your own words what a network layer is and why it is important in computer networks.

Answer: A network layer is a part of the network system that helps transmit data from one computer to another. It is important because it ensures data is sent correctly and reaches the right destination.

Question 2: List the main functions of the physical layer in a network.

Answer: The physical layer transmits raw data as electrical, optical, or radio signals over physical connections like cables or wireless links. It handles hardware and signal transmission.

Question 3: Name the layer responsible for routing data packets across different networks.

Answer: The Internet layer (or Network layer).

Question 4: Explain the purpose of the Transport layer in a network.

Answer: The Transport layer manages end-to-end communication between devices, ensuring data is delivered accurately and in the correct order.

Question 5: Imagine you are sending a message from your computer to a website. Describe how data passes through the different network layers during this process.

Answer: The data starts at the application layer on your computer, then moves down through the presentation, session, transport, network, data link, and physical layers. Each layer adds its own information to help deliver the message correctly and reliably. The data then travels over cables or wireless signals to reach the website's server, where it goes back up the layers to be displayed as a webpage.

Question 6: Complete the table with the correct layer names and their main functions: | Layer | Main Function | |---|---| | Physical | ? | | Data Link | ? | | Network | ? | | Transport | ? |

Answer: Physical - Transmits raw signals over physical media. Data Link - Handles data transfer between adjacent devices. Network - Routes data packets to their destination. Transport - Ensures reliable transmission of data between devices.

Question 7: Draw a simple diagram showing the seven layers of the OSI model as stacked blocks. Label each layer with its name.

Answer: A vertical stack of seven blocks from top to bottom: Application, Presentation, Session, Transport, Network, Data Link, Physical. Each block labeled accordingly.

Question 8: A network uses the Internet Protocol (IP) at the network layer. Describe what IP does in a network.

Answer: IP assigns unique addresses to devices and helps route data packets so they reach the correct destination across different networks.

Question 9: Identify which layer is responsible for error detection and correction during data transmission.

Answer: The Data Link layer is responsible for error detection and correction.

Question 10: Sketch a simple diagram of how two computers connect via a wireless network. Include labels for wireless signals, routers, and devices.

Answer: A sketch showing two computers connected wirelessly to a router with arrows indicating wireless signals between each computer and the router. The router is connected to the internet or a network.

Question 11: Explain why it is useful to have multiple layers in a network system rather than one big system doing everything.

Answer: Having multiple layers makes the system easier to manage, troubleshoot, and upgrade. Each layer handles specific tasks, which helps keep the network organized and reliable.