Automatic Priority Queue Assignment - ZyXEL Communications P-793H v3 User Manual

The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each packet
gets across the DiffServ network. Based on the marking rule, different kinds of traffic can be
marked for different kinds of forwarding. Resources can then be allocated according to the DSCP
values and the configured policies.

17.4.4 Automatic Priority Queue Assignment

If you enable QoS on the P-79X, the P-79X 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 P-79X. On the
P-79X, traffic assigned to higher priority queues gets through faster while traffic in lower index
queues is dropped if the network is congested.
Table 71 Internal Layer2 and Layer3 QoS Mapping
PRIORITY
QUEUE
0
1
2
3
4
5
6
7
Chapter 17 Quality of Service (QoS)
LAYER 2 LAYER 3
IEEE 802.1P USER
PRIORITY TOS (IP
(ETHERNET PRECEDENCE)
PRIORITY)
1 0
2
0 0
3 1
4 2
5 3
6 4
5
7 6
7
P-79X Series User's Guide
DSCP
000000
000000
001110
001100
001010
001000
010110
010100
010010
010000
011110
011100
011010
011000
100110
100100
100010
100000
101110
101000
110000
111000
177
IP PACKET
LENGTH (BYTE)
>1100
250~1100
<250