Protocol Priority

Protocol packets carry their own priority. You can modify the priority of a protocol packet to implement QoS.

Priority Marking

The priority marking function is to use ACL rules in traffic classification and reassign the priority for the packets matching the ACL rules.

Traffic Policing and Traffic Shaping

The network will be made more congested by plenty of continuous burst packets if the traffic of each user is not limited. The traffic of each user must be limited in order to make better use of the limited network resources and provide better service for more users. For example, a traffic flow can be limited to get only its committed resources during a time period to avoid network congestion caused by excessive bursts.

Traffic policing and traffic shaping is each a kind of traffic control policy used to limit the traffic and the resource occupied by supervising the traffic. The regulation policy is implemented according to the evaluation result on the premise of knowing whether the traffic exceeds the specification when traffic policing or traffic shaping is performed. Normally, token bucket is used for traffic evaluation.

Token bucket

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 1-5Evaluate the traffic with the token bucket

Packets to be sent through this port

Put tokens in the bucket at the set rate

Continue to send

Packet

classification

Token bucket

Drop

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3Com WX3000 operation manual Protocol Priority, Priority Marking, Traffic Policing and Traffic Shaping, Token bucket