HP 6400cl, Management Manual, Page: 282 / 664

Quality of Service (QoS): Managing Bandwidth More Effectively
Introduction
You can configure a QoS priority of 0 through 7 for an outbound packet. When
the packet is then sent to a port, the QoS priority determines which outbound
queue the packet uses:
Table 8-2. QoS Priority Settings and Operation
QoS Priority Setting Outbound Port Queue
1 - 2 low priority
0 - 3 normal priority
4 - 5 medium priority
6 - 7 high priority
If a packet is not in a VLAN-tagged port environment, then the QoS settings in
table 8-2 control only to which outbound queue the packet goes. Without VLAN
tagging, no 802.1p priority is added to the packet for downstream device use.
But if the packet is in a VLAN-tagged environment, then the above setting is
also added to the packet as an 802.1p priority for use by downstream devices
and applications (shown in table 8-3). In either case, an IP packet can also
carry a priority policy to downstream devices by using DSCP-marking in the
ToS byte.
Table 8-3. Mapping Series 5300XL and 3400cl/6400cl QoS Priority Settings to Device Queues
Priority Setting
in thitherto
Outbound Port
Queues in the
Switch
802.1p Priority Setting Added
to Tagged VLAN Packets
Leaving the Switch
Queue Assignment in Downstream Devices With:
8 Queues 3 Queues 2 Queues
1 Queue 1 1 (low priority) Queue 1 Queue 1
2 2 Queue 2 Queue 1
0 Queue 2 0 (normal priority) Queue 3 Queue 2
3 3 Queue 4
4 Queue 3 4 (medium priority) Queue 5 Queue 3
5 5 Queue 6 Queue 2
6 Queue 4 6 (high priority) Queue 7
7 7 Queue 8
8-8