1p priority – H3C Technologies H3C S10500 Series Switches User Manual
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Table 9 Description on DSCP values
DSCP value (decimal)
DSCP value (binary)
Description
46 101110
ef
10 001010
af11
12 001100
af12
14 001110
af13
18 010010
af21
20 010100
af22
22 010110
af23
26 011010
af31
28 011100
af32
30 011110
af33
34 100010
af41
36 100100
af42
38 100110
af43
8 001000
cs1
16 010000
cs2
24 011000
cs3
32 100000
cs4
40 101000
cs5
48 110000
cs6
56 111000
cs7
0 000000
be
(default)
802.1p priority
802.1p priority lies in the Layer 2 header and applies to occasions where Layer 3 header analysis is not
needed and QoS must be assured at Layer 2.
Figure 28 An Ethernet frame with an 802.1Q tag header
As shown in
, the four-byte 802.1Q tag header consists of the tag protocol identifier (TPID, two
bytes in length), whose value is 0x8100, and the tag control information (TCI, two bytes in length).
shows the format of the 802.1Q tag header. The Priority field in the 802.1Q tag header is called the
“802.1p priority”, because its use is defined in IEEE 802.1p.
shows the values for 802.1p
priority.