Data Link Control

• Line Discipline• Flow Control• Error Control

Functions of Data Link LayerFunctions of Data Link Layer

Figure 10-1

Figure 10-2

Figure 10-3

ENQ/ACKENQ/ACK

Figure 10-4

Figure 10-5

ENQ/ACKENQ/ACK

Multipoint DisciplineMultipoint Discipline

Figure 10-6

SelectSelectFigure 10-7

PollPollFigure 10-8

Figure 10-9

Flow control – set of procedures that tells the sender how much data it can transmit before it must wait for an acknowledgement from the receiver

Flow control – set of procedures that tells the sender how much data it can transmit before it must wait for an acknowledgement from the receiver

Stop and WaitStop and WaitFigure 10-10

Sliding WindowSliding Window

Figure 10-11

Figure 10-12

Sender Sliding WindowSender Sliding Window

Figure 10-13

Receiver Sliding WindowReceiver Sliding Window

Figure 10-14

Sliding Window ExampleSliding Window Example

Figure 10-14-continued

SenderSender

Figure 10-14-continued

ReceiverReceiver

Figure 10-15

Damaged FrameDamaged FrameFigure 10-16

Lost FrameLost FrameFigure 10-17

Lost ACKLost ACKFigure 10-18

Damaged FrameDamaged FrameFigure 10-19

Lost FrameLost FrameFigure 10-20

Lost ACKLost ACKFigure 10-21

Selective RejectSelective RejectFigure 10-22

Reference

Data Communications and Networking, 2nd ed.by Behrouz A. Forouzan