HP FlexNetwork NJ5000, User Manual

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402
DSCP value (decimal) DSCP value (binary) Description
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 Layer 2 packet headers and applies to occasions where Layer 3 header
analysis is not needed and QoS must be assured at Layer 2.
Figure 439 An Ethernet frame with an 802.1Q tag header
As shown in Figure 439 , the 4-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).
Figure 440 presents the format of the 802.1Q tag header. The priority in the 802.1Q tag
header is called "802.1p priority," because its use is defined in IEEE 802.1p. Table 143 presents the
values for 802.1p priority.