Local Management: Overview, Setup, and Navigation
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Transmit Queues Configuration Screen
The Transmit Queues Configuration Screen, Figure 36, allows the user to set each
port individually, or all ports simultaneously, to either transmit frames according
to the priority transmit queues set in the Advanced Priority Configuration Screen,
or transmit frames according to a priority based on a percentage of the port
transmission capacity allocated for each transmit queue.
Individual ports or all ports may be set to the STRICT 802.1 or WEIGHTED mode
of operation. In the STRICT 802.1 mode, frames are transmitted strictly according
to the priorities set in the Advanced Priority Configuration Screen. In this mode
all frames with a transmit queue of Q3 are transmitted first, followed by those
with transmit queues of Q2, then Q1, and finally, Q0.
In the WEIGHTED mode, a percentage (weighted value) is user-assigned to
establish the amount of transmission capacity assigned to frames associated with
each priority transmit queue (Q0 through Q3 with Q0 being the lowest priority
transmit queue). This allows the modification of the strict priority queues so that
frames with the lower priority queues are guaranteed some access time to the
transmitter.
For example, the transmit queues could be set as follows:
•
Q3 to 50%, so at least 50% of the Q3 frames are transmitted.
•
Q2 to 25%, so at least 25% of the Q2 frames are transmitted.
•
Q1 to 25%, so at least 25% of the Q1 frames are transmitted.
•
Q0 to 0%. No Q0 frames will be transmitted until Q3, Q2, and Q1 frames are
transmitted.
