Cisco Catalyst 2000 Configuration Handbook page 246

Table 13-1 Mapping of IP Precedence and DSCP Fields (Continued)
IP Precedence (3 Bits)
Name Value Bits
Immediate 2 010
Flash 3 011
Flash 4 100
Override
Critical 5 101
Internetwork 6 110
Control
Network 7 111
Control
1
IP precedence value 5 (DSCP EF) corresponds to the range of DSCP bits 101000 through 101111, or 40 to 47. However,
only the value 101110 or 46 is commonly used and is given the EF designation.
2
IP precedence values 6 and 7 consume the DSCP ranges 48 to 55 and 56 to 63, respectively. However, these values are
normally used by network control traffic and are not shown in the table for simplicity.
DSCP (6 Bits)
Per-Hop Class Drop
Behavior Selector Precedence
AF 2 1: Low
2: Medium
3: High
AF 3 1: Low
2: Medium
3: High
AF 4 1: Low
2: Medium
3: High
EF N/A N/A
N/A N/A N/A
N/A N/A N/A
Chapter 13: Quality of Service 225
Codepoint DSCP Bits
Name (Decimal)
AF21 010 010 (18)
AF22 010 100 (20)
AF23 010 110 (22)
AF31 011 010 (26)
AF32 011 100 (28)
AF33 011 110 (30)
AF41 100 010 (34)
AF42 100 100 (36)
AF43 100 110 (38)
EF
101 110 (46)
N/A 2
N/A
N/A 2
N/A
1