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QOS
Quality of service is the ability to provide different applications, users, or data flows with different
priority, or to guarantee a certain level of performance to a data flow. For example, a required bit rate,
delay, jitter, packet dropping probability and/or bit error rate may be guaranteed. Quality of service
guarantees are important if the network capacity is insufficient, especially for real-time streaming
multimedia applications such as voice over IP, online games and IP-TV, since these often require
fixed bit rate and are delay sensitive, and in networks where the capacity is a limited resource, for
example in cellular data communication.
QoS Property page
The
QoS Property
page allows for the configuration of global QoS mode settings and individual ports. It
also provides the individual port configurations to specify the type of QoS marking that should be used
on each port.
State:
Set to enable/disable QoS globally.
Trust Mode:
Select QoS trust mode
•
CoS:
Traffic is mapped to queues based on the CoS field in the VLAN tag, or based on the per-
port default CoS value (if there is no VLAN tag on the incoming packet), the actual mapping of
the CoS to queue can be configured on the CoS Mapping page.
•
DSCP:
All IP traffic is mapped to queues based on the DSCP field in the IP header. The actual
mapping of the DSCP to queue can be configured on the DSCP Mapping page. If traffic is not IP
traffic, it is mapped to the best effort queue.