Physical Layer

The physical layer is the first (and also the lowest) layer of network architecture in a communications network. The physical layer consists of the hardware technology needed to structure a network. The physical layer primarily functions to perform services requested by the data link layer, but also contributes to the underlying logical data structures that are performed by the higher-level functions. Included within the physical layer is information on the means for transmitting raw bits of data (as opposed to data packets) over a physical link. The physical layer is responsible for translating communication requests from the data link layer into actual hardware operations.