Exploring the Physical Layer of Networks

What are the main types of transmission media used in computer networks?

• Guided media (twisted pair, coaxial, fiber optic) and unguided media (wireless communication)

• Digital media (USB drives, hard disks)

• Optical media (CDs, DVDs)

• Physical media (paper, plastic)

Explain the difference between twisted pair, coaxial, and fiber optic cables.

• Fiber optic cables consist of copper wires twisted together.

• Twisted pair cables transmit data as light through glass fibers.

• Coaxial cables use only plastic insulation without a conductor.

• Twisted pair cables use copper wires, coaxial cables have a central conductor with shielding, and fiber optic cables transmit data as light through glass or plastic fibers.

What is the purpose of signal encoding techniques in data transmission?

• The purpose of signal encoding techniques in data transmission is to convert data into signals for accurate and efficient communication.

• To encrypt data for security purposes.

• To compress data for faster transmission speeds.

• To enhance the visual quality of data during transmission.

Name three common signal encoding techniques used in networking.

• Non-Return to Zero (NRZ), Manchester Encoding, Pulse Code Modulation (PCM)

• Frequency Shift Keying (FSK)

• Quadrature Amplitude Modulation (QAM)

• Amplitude Modulation (AM)

What is modulation and why is it important in communication systems?

• Modulation is the process of varying a carrier signal to encode information, and it is important for efficient data transmission and signal quality in communication systems.

• Modulation is the technique of filtering out noise from a signal.

• Modulation is the method of converting digital signals into analog signals.

• Modulation is the process of amplifying a signal to increase its strength.

Describe the difference between amplitude modulation (AM) and frequency modulation (FM).

• AM is used for digital signals; FM is for analog signals.

• AM varies frequency; FM varies amplitude.

• AM varies amplitude; FM varies frequency.

• AM and FM both vary amplitude.

What role do network interface cards (NICs) play in a computer network?

• NICs manage the power supply of the computer.

• Network interface cards (NICs) enable computers to connect to and communicate over a network.

• NICs are used to store data permanently.

• NICs are responsible for processing graphics.

What are the key components of a network interface card?

• Wireless access points

• Network cables

• Key components of a network interface card include a network processor, memory, a physical connector, circuitry, firmware, and a MAC address.

• Router components

How do physical layer protocols differ from data link layer protocols?

• Physical layer protocols focus on the physical transmission of data, while data link layer protocols manage data transfer and error correction.

• Data link layer protocols are responsible for physical transmission, while physical layer protocols manage data transfer.

• Physical layer protocols handle error correction, while data link layer protocols focus on transmission.

• Physical layer protocols operate at the application level, while data link layer protocols work at the network level.

List two examples of physical layer protocols and their functions.

• SMTP: Sends and receives email messages.

• 1. Ethernet: Defines standards for wired local area networks. 2. USB: Specifies connection and communication between devices and hosts.

• FTP: Transfers files over the internet.

• HTTP: Manages web page requests and responses.