EDS-508A/505A Series User’s Manual
Featured Functions
3-51
Configuring Traffic Prioritization
Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is
delivered consistently and predictably. The EDS can inspect IEEE 802.1p/1Q layer 2 CoS tags,
and even layer 3 TOS information, to provide a consistent classification of the entire network. The
EDS’s QoS capability improves your industrial network’s performance and determinism for
mission critical applications.
QoS Classification
The EDS supports inspection of layer 3 TOS and/or layer 2 CoS tag information to determine how
to classify traffic packets.
Queuing Mechanism
Setting
Description
Factory Default
Weighted Fair
The EDS has 4 priority queues. In the weighted fair
scheme, an 8, 4, 2, 1 weighting is applied to the four
priorities. This approach prevents the lower priority
frames from being starved of opportunity for
transmission with only a slight delay to the higher
priority frames.
Strict In
the
Strict-priority
scheme, all top-priority frames
egress a port until that priority’s queue is empty, and
then the next lower priority queue’s frames egress. This
approach can cause the lower priorities to be starved of
opportunity for transmitting any frames but ensures all
high priority frames to egress the switch as soon as
possible.
Weight Fair
Port Highest Priority
Setting
Description
Factory Default
Low/Normal/
Medium/High
Set the Port Default Priority of the ingress frames to
different priority queues. If the received packets are not
equipped with any tag information (COS, TOS) the
Normal
