The following entries are displayed on this screen:
Priority and CoS-mapping Config
Tag-id/Cos-id:
Indicates the precedence level defined by IEEE802.1P and the
CoS ID.
Queue TC-id:
Indicates the priority level of egress queue the packets with tag
and CoS-id are mapped to. The priority levels of egress queue are
labeled as TC0, TC1, TC2 and TC3.
Configuration Procedure:
Step Operation
Description
1 Configure
the
mapping
relation between the 802.1P
priority Tag/CoS and the TC
Required. On
QoS
→
DiffServ
→
802.1P/CoS mapping
page, configure the mapping relation between the
802.1P priority Tag/CoS and the TC.
2
Select a schedule mode
Required. On
QoS
→
DiffServ
→
Schedule Mode
page,
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 complete 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 of egress queue 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.
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