FIFO QUEUEING

Posted by AJ × 08:23

• Transmission Discipline: First-In, First-Out

• All packets are transmitted in order of their arrival.

• Buffering Discipline:- Discard arriving packets if buffer is full

• Cannot provide differential QoS to different packet flows

• Difficult to determine performance delivered

• Finite buffer determines a maximum possible delay

• Buffer size determines loss probability, but depends on arrival & packet length statistics.

FIFO Queuing with Discard Priority

FIFO queue management can be modified to provide different characteristics of packet-loss performance to different classes of traffic.

• The above Figure 7.42 (b) shows an example with two classes of traffic.

• When number of packets in a buffer reaches a certain threshold, arrivals of lower access priority (class 2) are not allowed into the system.

• Arrivals of higher access priority (class 1) are allowed as long as the buffer is not full.

All Syllabus