Network+ N10-009 Layer 1 (Physical)
The Physical layer is the OSI model's lowest layer, responsible for the actual transmission and reception of raw bits (0s and 1s) over physical media like copper cables, fiber optics, or wireless signals. It defines electrical, mechanical, and procedural characteristics—such as connectors, signal encoding, bit timing, and transmission modes—to enable reliable data movement.
Physical Layer
Key Terms
Physical Layer
Where transmission of bits across the network occurs and includes physical and electrical network characteristics.
Transition Modulation
If it changes during the clock cycle, then a 1 is represented (otherwise, a o is represented).
Asynchronous
Uses start and stop bits to indicate when transmissions occur from the sender to the receiver.
Synchronous
Uses a reference clock to coordinate the transmissions by both sender and receiver.
Broadband
Divides bandwidth into separate channels.
Baseband
Uses all available frequencies on a medium (cable) to transmit data.
Related Flashcard Decks
| Term | Definition |
|---|---|
Physical Layer | Where transmission of bits across the network occurs and includes physical and electrical network characteristics. |
Transition Modulation | If it changes during the clock cycle, then a 1 is represented (otherwise, a o is represented). |
Asynchronous | Uses start and stop bits to indicate when transmissions occur from the sender to the receiver. |
Synchronous | Uses a reference clock to coordinate the transmissions by both sender and receiver. |
Broadband | Divides bandwidth into separate channels. |
Baseband | Uses all available frequencies on a medium (cable) to transmit data. |
Time-Division Mutiplexing (TDM) | Each session takes a turn, using time slots, to share the medium between all users. |
Statistical Time-Division Mutiplexing (StatTDM) | Dynamically allocates the time slots on an as-needed basiis. |