Appendix B Introduction To Packet Precedences; Ip Precedence And Dscp Values - H3C S5120-EI Series Configuration Manual

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Appendix B Introduction to Packet Precedences

IP Precedence and DSCP Values

Figure 12-1 ToS and DS fields
As shown in Figure
2) represent IP precedence from 0 to 7. According to RFC 2474, the ToS field of the IP header is
redefined as the differentiated services (DS) field, where a DSCP value is represented by the first six
bits (0 to 5) and is in the range 0 to 63. The remaining two bits (6 and 7) are reserved.
Table 12-1 Description on IP precedence
IP precedence (decimal)
0
1
2
3
4
5
6
7
Table 12-2 Description on DSCP values
DSCP value (decimal)
46
10
12-1, the ToS field of the IP header contains eight bits, and the first three bits (0 to
IP precedence (binary)
000
001
010
011
100
101
110
111
DSCP value (binary)
101110
001010
12-1
Description
Routine
priority
immediate
flash
flash-override
critical
internet
network
Description
ef
af11