3
Map the DSCP priority to the
priority level
Required. Select DSCP priority and the corresponding
priority level.
4 Select a schedule mode Required. Log on to the Schedule Mode page to
select a schedule mode.
9.1.4 Schedule Mode
On this page you can select a schedule mode for the switch. When the network is congested, the
problem that many packets compete for resources must be solved, usually in the way of queue
scheduling. The switch will control the forwarding sequence of the packets according to the priority
queues and scheduling algorithms you set. On this switch, the priority levels are labeled as TC0,
TC1… TC3.
Choose the menu QoS→DiffServ→Schedule Mode to load the following page.
Figure 9-9 Schedule Mode
The following entries are displayed on this screen:
Schedule Mode Config
SP-Mode: Strict-Priority Mode. In this mode, the queue with higher priority
will occupy the whole bandwidth. Packets in the queue with lower
priority are sent only when the queue with higher priority is empty.
WRR-Mode: Weight Round Robin Mode. In this mode, packets in all the
queues are sent in order based on the weight value for each
queue. The weight value ratio of TC0, TC1, TC2 and TC3 is
1:2:4:8.
SP+WRR-Mode: Strict-Priority + Weight Round Robin Mode. In this mode, this
switch provides two scheduling groups, SP group and WRR
group. Queues in SP group and WRR group are scheduled strictly
based on strict-priority mode while the queues inside WRR group
follow the WRR mode. In SP+WRR mode, TC3 is in the SP group;
TC0, TC1 and TC2 belong to the WRR group and the weight value
ratio of TC0, TC1 and TC2 is 1:2:4. In this way, when scheduling
queues, the switch allows TC3 to occupy the whole bandwidth
following the SP mode and the TC0, TC1 and TC2 in the WRR
group will take up the bandwidth according to their ratio 1:2:4.
Equ-Mode: Equal-Mode. In this mode, all the queues occupy the bandwidth
equally. The weight value ratio of all the queues is 1:1:1:1.
9.2 Bandwidth Control
Bandwidth function, allowing you to control the traffic rate and broadcast flow on each port to
ensure network in working order, can be implemented on Rate Limit and Storm Control pages.
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