Data Link Layer & Physical Layer Difference

Data link layer primary functions are

Communication with the upper layer (network layer)

Segmentation: Making of frames form the packets (data gram) of data received.

Bit insertion (start bit, stop bit, parity bits) used for error checking and correct delivery of data.

Communication with the Physical layer.

It mean it deals with reliable transit of data across a physical link , physical addressing, network topology, physical link management, error notification, ordered delivery of frames, and flow control.

Physical layer

It is the first layer of OSI model. It is the only one layer where data is physically moved across the network interface. All of the other layers perform useful functions to create messages to be sent, but they must all be transmitted down the protocol stack to the physical layer, where they are actually sent out over the network.

Bit insertion (start bit, stop bit, parity bits) used for error checking and correct delivery of data.

Communication with the Physical layer.

It mean it deals with reliable transit of data across a physical link , physical addressing, network topology, physical link management, error notification, ordered delivery of frames, and flow control.