User manual

C HAPTER 11 | Class of Service
Layer 2 Queue Settings
– 129 –
ES-2000 Series
Figure 68: Setting the Queue Mode (Strict and WRR)
MAPPING COS VALUES
TO EGRESS QUEUES
Use the Traffic > Priority > PHB to Queue page to specify the hardware
output queues to use based on the internal per-hop behavior value. (For
more information on exact manner in which the ingress priority tags are
mapped to egress queues for internal processing, see "Mapping CoS
Priorities to Internal DSCP Values" on page 136).
The switch processes Class of Service (CoS) priority tagged traffic by using
four priority queues for each port, with service schedules based on strict
priority, Shaped Deficit Weighted Round-Robin (SDWRR), or a combination
of strict and weighted queuing. Up to eight separate traffic priorities are
defined in IEEE 802.1p. Default priority levels are assigned according to
recommendations in the IEEE 802.1p standard as shown in Tabl e 1 2. This
table indicates the default mapping of internal per-hop behavior to the
hardware queues. The actual mapping may differ if the CoS priorities to
internal DSCP values have been modified (page 136).
Table 12: IEEE 802.1p Egress Queue Priority Mapping
Priority 01234567
Queue 10012233