In Network Security, the data link layer is the second layer from the bottom in the OSI model. The data link layer consists of the following sub-layers:
The data link layer manages sets of bits for
The data link protocols include PPP, FDDI, Ethernet, and Token Ring.
The data link layer represents the physical address of the sender or receiver if the frames are assigned to the various systems on the network. This is done by adding a header to the frame.
In half-duplex mode, data can be transmitted one node at a time.
During a full-duplex, data can be sent by both nodes at the same time.
The data link layer divides the data into bits, which are received via the network layer in the form of
An error that is caused when noise during transmission or any other technical issue that would cause bits to flip is detected.
The bits that are flipped due to errors are corrected and then flipped back to the original bits. The receiving node detects the error, and the data link layer also detects missing frames.
Flow control prevents the receiver’s buffer from overflowing. The data link layer manages the speed of transmission of data at the ends.
The data link layer transmits the data from the network layer without any errors.
Some of the issues of the data link layer are:
It can be difficult to manage the transmission of data so that the slow receiver end is not overwhelmed by a fast sender end.
Transmitted data has the potential for errors.
It provides an unacknowledged interface surface to the network layer by sending data from the network layer of the sending machine to the receiver machine’s network layer.