In the OSI model, which layer describes the electrical and physical connection between communicating units?

The Physical layer in the OSI model is responsible for defining the electrical and physical connection between communicating units. This includes the physical media used for transmission, such as cables and connectors, as well as the electrical signals that travel over those media. The Physical layer ensures that data can be transmitted over the network by specifying properties like voltage levels, timing, and physical data rates.

This layer is fundamental because it lays the groundwork for communication between devices; without it, higher layers would have no means to transmit data. The focus of the Physical layer is on hardware and transmission technologies, making it distinct from other layers that manage data packaging, addressing, and error correction. Therefore, identifying the Physical layer as the one describing the electrical and physical connection is accurate and aligns with its role within the OSI model.