HP ProCurve Series 6120 Blade Switches Advanced Traffic Management Guide

5-12
Quality of Service (QoS): Managing Bandwidth More Effectively
Preparation for Configuring QoS
f. VLAN Priority (requires at least one tagged VLAN on the network)
g. Source-Port
h. Incoming 802.1p Priority (requires at least one tagged VLAN on the
network). In a tagged VLAN environment, the incoming 802.1p prior-
ity is used as the default QoS classifier if no QoS classifier with a
higher precedence matches
2. Select the QoS option you want to use. Table 5-6 lists the traffic types (QoS
classifiers) and the QoS options you can use for prioritizing or setting a
policy on these traffic types:
Table 5-6. QoS Marking Supported by QoS Classifiers
QoS Classifiers
Type of QoS Marking Used to
Prioritize Outbound Traffic
802.1p Priority
1
Only DSCP Policy
2
: DSCP codepoint with
802.1p Priority
UDP/TCP Supported Supported
IP Device Supported Supported
IP Precedence Supported
3
Not Supported
IP DiffServ Supported Supported
L3 Protocol Supported Not Supported
VLAN ID Supported Supported
Source Port Supported Supported
1
When you configure only the 802.1p priority to mark packets that match a QoS classifier, the
selected traffic is prioritized and sent to the corresponding outbound port queue on the
switch (see Table 5-1). VLAN-tagged ports are necessary to carry the 802.1p priority in a
packet header to downstream devices.
2
When you configure a DSCP policy to mark packets that match a QoS classifier, the selected
traffic is also prioritized according to the associated 802.1p priority and sent to the
corresponding outbound port queue on the switch. VLAN-tagged ports carry the 802.1p
priority in a packet header to downstream devices. In addition, you can configure
downstream devices to read the DSCP value in IP packets and implement the service policy
implied by the codepoint.
3
When using a QoS IP Precedence classifier, the 802.1p priority is automatically assigned to
matching packets based on the IP precedence bit set in the packet header.