What are the two layers of the OSI model combined into the TCP/IP Link layer?

The two layers of the OSI model that are combined into the TCP/IP Link layer are indeed the Data Link and Physical layers. In the OSI model, the Data Link layer is responsible for node-to-node data transfer and error correction, ensuring that the data packets are successfully transmitted over the physical medium. It handles framing, addressing, and access control to the medium.

The Physical layer, on the other hand, deals with the physical connections between devices, including the electrical, mechanical, and procedural aspects to activate and maintain that connection. It defines the hardware means of sending and receiving data on a carrier, such as cables, switches, and port.

In the TCP/IP model, which is more simplified than the OSI model, these two layers are merged into the Link layer (also referred to as the Network Interface or Data Link layer), encompassing both aspects that are concerned with the physical transmission of data over a network and the management of how data packets are framed for network access. This combination streamlines the communication model by efficiently encapsulating the functionality that is lower level in the data transmission process.