DSCP/DiffServ and IP PrecedenceΒΆ

Differentiated Services Code Point (DSCP) is a means of classifying and managing network traffic and of providing quality of service (QoS) in modern Layer 3 IP networks. It uses the 6-bit Differentiated Services (DS) field in the IP header for the purpose of packet classification.

IP Precedence is another means to classify and differentiate traffic in a Quality of Service enabled network. The relationship between DSCP and IP Precedence is detailed in the table below.

DSCP name

DS (binary)

DS (decimal)

IP Precedence

CS0

000000

0

0

CS1

001000

8

1

AF11

001010

10

1

AF12

001100

12

1

AF13

001110

14

1

CS2

010000

16

2

AF21

010010

18

2

AF22

010100

20

2

AF23

010110

22

2

CS3

011000

24

3

AF31

011010

26

3

AF32

011100

28

3

AF33

011110

30

3

CS4

100000

32

4

AF41

100010

34

4

AF42

100100

36

4

AF43

100110

38

4

CS5

101000

40

5

EF

101110

46

5

CS6

110000

48

6

CS7

111000

56

7