Moxa Technologies EDS-518A Series - Manual (Page 47)

EDS-518A Series User’s Manual Featured Functions
3-32
Queuing Mechanism
Setting Description Factory Default
Weighted Fair EDS-518A 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
Enable/Disable Set the Port Priority of the ingress frames to “High”
queues. Disable
Inspect TOS
Setting Description Factory Default
Enable/Disable Select the option to enable EDS-518A to inspect the
Type of Service (TOS) bits in IPV4 frame to determine
the priority of each frame. Enable
Inspect COS
Setting Description Factory Default
Enable/Disable Select the option to enable EDS-518A to inspect the
802.1p COS tag in the MAC frame to determine the
priority of each frame. Enable
NOTE The priority of an ingress frame is determined in order by:
1. Port
Highest Priority
2. Inspect TOS
3. Inspect CoS
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.