Appendix B Introduction To Packet Precedences; Ip Precedence And Dscp Values - H3C S7500E Series Configuration Manual

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Appendix B Introduction to Packet Precedences

IP Precedence and DSCP Values

Figure 15-1 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 15-1 Description on IP precedence
IP precedence (decimal)
0
1
2
3
4
5
6
7
15-1, 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
15-1
Description
Routine
priority
immediate
flash
flash-override
critical
internet
network