Question

Briefly list and describe several functions of the Data Link layer of any given communications protocol.

Answer 1

A communication protocol, is a kind of protocol through which more than one entity can do communications via physical, hardware or any software method. Data link layer is also divided into two sub layer parts 1) LLC (logical link control ) 2) MAC ( media access control ) . (OSI)  (Open Systems Interconnection) , which is also a communication protocol, and they have 7 layers in it :

a) applications layer.

b) presentation layer

c) session layer.

d) transport layer.

  e) network layer.

  f) data link layer.

g) physical layer.

Among all the layers data link layer, is explained below:

Data link layer, transfers the physical layer to required link, and it helps to make the physical layer error-free to the upper layer. now data link layer performs other qualities, which are listed below:

1) framing : the data link layer helps to divide each bits which are collected from the network layer into doable data units called farmes.

2) physical addressing : the data link layer passes away different frames to different system and adds a header to the frame which helps the sender and the receiver of the frame.

3) flow control : the data link layer inflict flow control technique to avoid massive receiver, and this happens when the rate at which the data are occupied by the receiver is less than the rate at which data are produced for sending it.

4) error control : the data link layer have a dedictaed mechanism where it adds devoted to phyiscal layer to detect and recommit damaged, lost and duplicate frames.

5) access control : the data link layer mechanism is required to judge which device has taken the control over the link, when more two devices are connected to the same link.