3Com Switch 4210 9-Port, Configuration Manual

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QoS Supported By Switch 4210 Family 305
Port Rate Limiting Port rate limiting refers to limiting the total rate of inbound or outbound packets
on a port.
Port rate limiting can be implemented through token buckets. The token bucket
can be considered as a container with a certain capacity to hold tokens. The
system puts tokens into the bucket at the set rate. When the token bucket is full,
the extra tokens will overflow and the number of tokens in the bucket stops
increasing.
Figure 95 Diagram for LR
If you perform port rate limiting configuration for a port, the token bucket
determines the way to process the packets to be sent by this port or packets
reaching the port. Packets can be sent or received if there are enough tokens in
the token bucket; otherwise, they will be dropped.
Queue Scheduling When the network is congested, the problem that many packets compete for
resources must be solved, usually through queue scheduling.
2 0
3 1
4 2
5 2
6 3
7 3
Table 225 IP-precedence-to-local-precedence mapping table
IP precedence Local precedence
Token bucket
Drop
Packet
classification
Packets to be sent
through this port
Continue to send
Put tokens in the bucket at the set rate