LevelOne GTL-2691 - Manual (Page 283)

C HAPTER 10 | Class of Service
Layer 3/4 Priority Settings
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Figure 127: Mapping IP DSCP Priority Values
M APPING IP
P RECEDENCE
Use the Traffic > Priority > IP Precedence to CoS page to map IP
Precedence priorities found in ingress packets to CoS values for internal
priority processing.
CLI R EFERENCES
◆ "map ip precedence (Global Configuration)" on page 1163
◆ "map ip precedence (Interface Configuration)" on page 1166
◆ "show map ip precedence" on page 1168
C OMMAND U SAGE
The Type of Service (ToS) octet in the IPv4 header includes three
precedence bits defining eight different priority levels ranging from highest
priority for network control packets to lowest priority for routine traffic. The
default IP Precedence values are mapped one-to-one to Class of Service
values (i.e., Precedence value 0 maps to CoS value 0, and so forth). Bits 6
and 7 are used for network control, and the other bits for various
application types. ToS bits are defined in the following table.
Table 17: Usage of ToS Bits
Priority Level Traffic Type
0 Routine
1 Priority
2 Immediate
3 Flash
4 Flash Override
5 Critical
6 Internetwork Control
7 Network Control