7-8
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 7 Marking Traffic
IP Differentiated Services Code Point Marking
DSCP Values
The following differentiated services (DiffServ) RFCs define DSCP values:
•
RFC-2474,
Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers
•
RFC-2475,
An Architecture for Differentiated Services
•
RFC-2597,
Assured Forwarding PHB Group
•
RFC-2598,
An Expedited Forwarding PHB
The RFCs do not dictate the way to implement PHBs; this is the responsibility of the vendor. Cisco
implements queuing techniques that can base their PHB on the IP precedence or DSCP value in the IP
header of a packet. Based on DSCP or IP precedence, traffic can be put into a particular service class.
Packets within a service class are treated the same way.
Table 7-4
lists only the DSCP values suggested by the DiffServ RFCs.
Table 7-4
DSCP Values
DSCP Value
DSCP Name
Binary Value
Defined in RFC
0
Best Effort or Default
000000
2475
8
CS1
001000
16
CS2
010000
24
CS3
011000
32
CS4
100000
40
CS5
101000
48
CS6
110000
56
CS7
111000
10
AF11
001010
2597
12
AF12
001100
14
AF13
001110
18
AF21
010010
20
AF22
010100
22
AF23
010110
26
AF31
011010
28
AF32
011100
30
AF33
011110
34
AF41
100010
36
AF42
100100
38
AF43
100110
46
EF
101110
2598