DIS-200G Series Industrial Gigabit Ethernet Smart Managed Switch
87
7.
Quality of Service (QoS)
802.1p Priority
Port Rate Limiting
Port Trust State
802.1p Priority
This window is used to view and configure the port’s scheduler method and default CoS settings.
To view the following window, click
QoS > 802.1p Priority
, as shown below:
The fields that can be configured in
Port Scheduler Method
are described below:
Parameter
Description
From Port / To Port
Select the appropriate port range used for the configuration here.
Scheduler Method
Select the scheduler method that will be applied to the specified
port(s). Options to choose from are Strict Priority (
SP
) and
Weighted Round-Robin (
WRR
). By default, the output queue
scheduling algorithm is
WRR
.
To set a CoS queue in the
SP
mode, any higher priority CoS
queue must also be in the strict priority mode.
WRR
operates by transmitting permitted packets into the transmit
queue in a round robin order. Initially, each queue sets its weight
to a configurable weighting. Every time a packet from a higher
priority CoS queue is sent, the corresponding weight is subtracted
by 1 and the packet in the next lower CoS queue will be serviced.
When the weight of a CoS queue reaches zero, the queue will not
be serviced until its weight is replenished. When weights of all CoS
queues reach 0, the weights get replenished at a time.
Figure 7-1 802.1p Priority window
