The physical layer is the first and lowest layer in the OSI (Open Systems Interconnection) model of computer networking.
• It is responsible for the transmission and reception of unstructured raw data between a device and a physical transmission medium.
• It defines the hardware elements involved in the process of data transmission, including cables, switches, network interface cards, and more.
• It deals with the electrical, mechanical, and procedural interfaces to the physical medium, ensuring that data is transmitted in a bit stream format.
Key Functions of the Physical Layer:
- It transfers data bit by bit or symbol by symbol.
- It converts digital data into analog signals or vice versa.
- It handles simplex, half-duplex, and full-duplex transmission modes.
- It defines the physical layout and arrangement of devices in the network.
- It performs bit synchronization, which means that only one bit needs to be transferred from one system to another at a time.
