Mapping Ip Precedence; Table 3-12. Mapping Ip Precedence; Figure 3-77. Selecting Ip Precedence Priority - SMC Networks 100BASE-TX Management Manual

Mapping IP Precedence

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.
Priority Level Traffic Type
7 Network Control
6 Internetwork Control
5 Critical
4 Flash Override
Command Attributes
• IP Precedence Priority Table – Shows the IP Precedence to CoS map.
• Class of Service Value – Maps a CoS value to the selected IP Precedence value.
Note that "0" represents low priority and "7" represent high priority.
Web* – Click Priority, IP Precedence Priority. Select the required interface, select an
entry from the IP Precedence Priority Table, enter a value in the Class of Service
Value field, and then click Apply.

Figure 3-77. Selecting IP Precedence Priority

Table 3-12. Mapping IP Precedence

Priority Level
3
2
1
0
Class of Service Configuration
Traffic Type
Flash
Immediate
Priority
Routine
3
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