H3C S5120-EI Series, Operation Manual

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10-3
Input priority value dot1p-lp mapping dot1p-dp mapping
2 1 0
3 3 0
4 4 0
5 5 0
6 6 0
7 7 0
Table 10-3
The default
dscp-lp
,
dscp-dp
,
dscp-dot1p
, and
dscp-exp
priority mapping tables
Input priority value dscp-dp mapping dscp-dot1p mapping
DSCP Drop precedence (dp) 802.1p priority (dot1p)
0 to 7 0 0
8 to 15 0 1
16 to 23 0 2
24 to 31 0 3
32 to 39 0 4
40 to 47 0 5
48 to 55 0 6
56 to 63 0 7
Appendix C Introduction to Packet Precedences
IP Precedence and DSCP Values
Figure 10-1
ToS and DS fields
As shown in
Figure 10-1 , the ToS field of the IP header contains eight bits, and the first three bits (0 to 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.