ZyXEL Communications P-660R-11V3 User Manual

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 Chapter 11 Quality of Service (QoS)
P-660R-T1 v3 User’s Guide
97
11.3.3  Automatic Priority Queue Assignment
If you enable QoS on the ZyXEL Device, the ZyXEL Device can automatically base on the 
IEEE 802.1p priority level, IP precedence and/or packet length to assign priority to traffic 
which does not match a class.
The following table shows you the internal layer-2 and layer-3 QoS mapping on the ZyXEL 
Device. On the ZyXEL Device, traffic assigned to higher priority queues gets through faster 
while traffic in lower index queues is dropped if the network is congested.
Table 30   Internal Layer2 and Layer3 QoS Mapping
PRIORITY 
QUEUE
LAYER 2
LAYER 3
IEEE 802.1P USER 
PRIORITY 
(ETHERNET 
PRIORITY)
TOS (IP 
PRECEDENCE)
DSCP
IP PACKET 
LENGTH (BYTE)
0
1
0
000000
1
2
2
0
0
000000
>1100
3
3
1
001110
001100
001010
001000
250~1100
4
4
2
010110
010100
010010
010000
5
5
3
011110
011100
011010
011000
<250
6
6
4
100110
100100
100010
100000
5
101110
101000
7
7
6
110000
111000
7