HP 445946-001 - Manual (Page 98)

Quality of Service
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• Class Selector (CS)—This PHB has eight priority classes, with CS7 representing the highest priority,
and CS0 representing the lowest priority, as shown below. CS PHB is described in RFC 2474.
Table 18 Class selector priority classes
Priority Class Selector DSCP
Highest CS7 56
CS6 48
CS5 40
CS4 32
CS3 24
CS2 16
CS1 8
Lowest CS0 0
QoS levels
The following table shows the default service levels provided by the switch, listed from highest to lowest
importance:
Table 19 Default QoS service levels
Service Level Default PHB 802.1p Priority
Critical CS7 7
Network Control CS6 6
Premium EF, CS5 5
Platinum AF41, AF42, AF43, CS4 4
Gold AF31, AF32, AF33, CS3 3
Silver AF21, AF22, AF23, CS2 2
Bronze AF11, AF12, AF13, CS1 1
Using 802.1p priorities to provide QoS
The HP 10GbE switch software provides Quality of Service functions based on the priority bits in a
packet’s VLAN header. (The priority bits are defined by the 802.1p standard within the IEEE 802.1q
VLAN header.) The 802.1p bits, if present in the packet, specify the priority given to packets during
forwarding. Packets with a numerically higher (non-zero) priority are given forwarding preference over
packets with lower priority.
Packets with a priority mapped to a higher Class of Service (COS) and COS queue (COSq) weight are
given forwarding preference over packets with priority mapped to a lower COS and COSq weight. The
scheduling scheme is Weight Round Robin (WRR), with user-configurable weight from 0 to 15 for a
COSq. The switch can be configured with either two or eight output Class of Service queues (COSq).