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USER GUIDE - M0SWTA1903Iv09 - V09 March 2019
lower priority when the higher priority queues are empty. The WFQ policy guarantees a
weighted service for all the priority, but pre-eminently to queues with a high priority.
The service policy is unique for level 2 service. The parameters are the priority 802.1q or
the DSCP field in the IP header (level 3).
The priority supported by standard 802.1p admits values of between 0 and 7. The untagged
frames received are given a priority within that range, depending on the interface through
which they were received, pursuant to the section entitled QoS Port Table. Tagged frames
may include either the VLAN identifier as the priority (tagged) or only the priority (priority
tagged, VLAN = 0). If the VLAN identifier is included, they are processed in accordance
with the rules of the VLANs submenu, in such a way that the priority may be overridden. If,
on the contrary, they only include the priority, they are processed in accordance with the
section entitled QoS Port Table.
The sections and their configuration parameters are as follows:
Weight Fair Scheduling:
• Weighted Fair. This establishes the level 2 priority service policy. When the NO
option is enabled, the policy is Priority. When the Yes option is enabled, the policy
is WFQ.
Priority:
This section establishes the classification conditions of the frames in each one of the
three existing queues according to the 802.1q priority value, regardless of the
assignation mechanism, or its process.
• #. This identifies the value of the priority associated with frame 802.1 (it covers the
whole range of values permitted by the standard).
• Queue. This establishes the queue priority in which the traffic coinciding with the
priority value indicated by the # field will be inserted. The values permitted identify
the four internal priorities: High, Medium, Low or Mgmt.
 Although it is available, it is recommended to reserve the Mgmt priority for
exclusive use as priority 7, avoiding the use of such priority for user traffic.