Westermo MDI-110 Series, User Manual

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Use an 8,4,2,1 weighted fair queuing scheme. This is also known as WRR
(Weight Round Robin) . The switch will follow 8:4:2:1 rate to process the packets
in a queue from the highest priority to the lowest. For example, the system will
process 8 packets with the highest priority in the queue, 4 with middle priority, 2
with low priority, and 1 with the lowest priority at the same time.
Use a strict priority scheme. Packets with higher priority in the queue will always
be processed first, except that there is no packet with higher priority.
Port Setting
CoS column is to indicate default port priority value for untagged or
priority ‐ tagged frames. When the switch receives the frames, it will attach the
value to the CoS field of the incoming VLAN ‐ tagged packets. You can enable
0,1,2,3,4,5,6 or 7 to the port.
Trust Mode is to indicate Queue Mapping types for you to select.
COS Only: Port priority will only follow COS ‐ Queue Mapping you have assigned.
DSCP Only: Port priority will only follow DSCP ‐ Queue Mapping you have
assigned.
COS first: Port priority will follow COS ‐ Queue Mapping first, and then
DSCP ‐ Queue Mapping rule.
DSCP first: Port priority will follow DSCP ‐ Queue Mapping first, and then
COS ‐ Queue Mapping rule.
Default priority type is COS Only . The system will provide default COS ‐ Queue
table to which you can refer for the next command.
After configuration, press Apply to enable the settings.
4.6.2 CoS ‐ Queue Mapping
This page is to change CoS values to Physical Queue mapping table. Since the
switch fabric only supports 4 physical queues, Lowest, Low, Middle and High.
Users should therefore assign how to map CoS value to the level of the physical
queue.
You can freely assign the mapping table or follow the suggestion of the 802.1p
standard. Westermo uses 802.p suggestion as default values. You can find CoS
values 1 and 2 are mapped to physical Queue 0, the lowest queue. CoS values 0
and 3 are mapped to physical Queue 1, the low/normal physical queue. CoS
values 4 and 5 are mapped to physical Queue 2, the middle physical queue. CoS
values 6 and 7 are mapped to physical Queue 3, the high physical queue.