Physical Layer Flashcards
(20 cards)
What is the main function of the Physical Layer?
Transmit raw bits over a physical medium without interpreting meaning or structure.
What are the two main types of transmission media?
Guided (wired) and Unguided (wireless).
Name three guided media examples.
Twisted pair cables, coaxial cables, and fiber optic cables.
Name three unguided media examples.
Radio waves, microwaves, and infrared.
What are the two main types of signals?
Analog (continuous) and Digital (discrete).
What encoding technique is used in Ethernet?
Manchester Encoding.
What are three multiplexing techniques?
TDM (Time Division), FDM (Frequency Division), WDM (Wavelength Division).
Name four modulation techniques.
ASK, FSK, PSK, QAM.
Which devices operate at the Physical Layer?
Hubs, repeaters, cables, connectors, and NICs.
Why doesn’t the Physical Layer handle errors?
It only transmits bits; error handling requires higher-level interpretation.
What standard governs Ethernet at the Physical Layer?
IEEE 802.3.
What standard governs Wi-Fi at the Physical Layer?
IEEE 802.11.
What is the difference between a hub and switch?
Hub (Layer 1) broadcasts to all ports; switch (Layer 2) uses MAC addresses to send to specific ports.
What does NRZ stand for in encoding?
Non-Return to Zero.
What is the purpose of synchronization in the Physical Layer?
Ensures sender and receiver interpret bits at the same timing.
What are the physical characteristics defined by this layer?
Voltages, cable types, pin layouts, and connector shapes.
What topology arrangements exist at the Physical Layer?
Bus, Ring, Star, Mesh, etc.
What is the role of a repeater?
Boosts weak signals to extend transmission distance.
How does fiber optic transmission differ from copper wires?
Uses light pulses instead of electrical signals, enabling higher speeds and longer distances.
What does QAM stand for in modulation?
Quadrature Amplitude Modulation.
