TN-5516/5518 User’s Manual Featured Functions
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Configuring Traffic Prioritization
Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is
delivered consistently and predictably. The TN-5500 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
TN-5500’ QoS capability improves your industrial network’s performance and determinism for
mission critical applications.
QoS Classification
The TN-5500 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
Weight Fair TN-5500 has 4 priority queues. In the weight 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