Moxa Technologies EDS-508 Queuing Mechanism, Inspect TOS, Inspect COS, Default Port Priority

EDS-508 Series User’s Manual Featured Functions

MOXA EtherDevice Switch 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
		EDS-508 has 4 priority queues. In the weighted fair
		scheme, an 8, 4, 2, 1 weighting is applied to the four
	Weight Fair	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
		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.
	Strict	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
		Check the checkbox to enable EDS-508 to inspect the
	Enable/Disable	Type of Service (TOS) bits in IPV4 frame to	Enable
		determine the priority of each frames.
Inspect COS

	Setting	Description	Factory Default
	Enable/Disable	Check the check box to enable EDS-508 to inspect the	Enable
		802.1p COS tag in the MAC frame to determine the
		priority of each frame.
Default Port Priority

		Setting	Description	Factory Default
			Set the Port Default Priority of the ingress frames to
	Low/Normal/		different priority queues. If the received packets are	Normal
	Medium/High		not equipped with any tag information (CoS, TOS) the
			default port priority will take effect.
NOTE	The priority of an ingress frame is determined in order by:
	1.	Inspect TOS
	2.	Inspect CoS
	3.	Default Port Priority
NOTE	The designer can enable these classifications individually or in combination. For instance, if a
	‘hot,’ higher priority port, is required for a network design, “Inspect TOS” and “Inspect CoS” can

be disabled. This setting leaves only port default priority active, which results in all ingress frames being assigned the same priority on that port.

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