Answer:
Physical Layer
Step-by-step explanation:
It is the physical layer that deals with the transfer of the data in bits over the cables. The Network interface card like RS-485, Bluetooth, wireless options, GSM, etc is the physical component with which the Physical layer comprises and deals. in fact, it provides the electrical and mechanical interface between one device and the other device. And the data transferred are in the form of electrical signals, and hence Physical layer does not require any header or footer. However, the transport layer, the Internet layer, and the application layers all require header and footers, as they have useful information that they need for processing at their level respectively.