Moxa Technologies PT-7728 Configuring Traffic Prioritization, QoS Classification, Inspect TOS

PT-7728 User’s Manual Featured Functions

Configuring Traffic Prioritization

Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is delivered consistently and predictably. The PT-7728 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 PT-7728’ QoS capability improves your industrial network’s performance and determinism for mission critical applications.

QoS Classification

The PT-7728 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	PT-7728 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.	Weight Fair
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.
Inspect TOS
Setting	Description	Factory Default
Enable/Disable	This enables or disables the PT-7728 to inspect the Type	Enable
	of Service (TOS) bits in IPV4 frame to determine the
	priority of each frame.

3-37