H3C Technologies H3C S10500 Series Switches - Manual (Page 94)

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Input priority value exp-dp mapping
1 0
2 0
3 0
4 0
5 0
6 0
7 0
Appendix B Introduction to packet precedences
IP precedence and DSCP values
Figure 27 ToS and DS fields
As shown in Figure 27 , the ToS field in the IP header contains eight bits. The first three bits (0 to 2)
represent IP precedence from 0 to 7. According to RFC 2474, the ToS field 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 8 Description on IP precedence
IP precedence (decimal) IP precedence (binary) Description
0 000 Routine
1 001 priority
2 010 immediate
3 011 flash
4 100 flash-override
5 101 critical
6 110 internet
7 111 network