layer 1 ⇝
Layer one, the lowest layer in the OSI seven layer model. The physical layer encompasses details such as electrical and mechanical connections to the network, transmission of binary data as changing voltage levels on wires or similar concepts on other connectors, and data rates.The physical layer is used by the data link layer. Example physical layer protocols are CSMA/CD, token ring and bus.
Last updated: 2004-06-29