Congestion Management Policy - H3C S3610-28P Operation Manual

Operation Manual – QoS
H3C S3610&S5510 Series Ethernet Switches
Chapter 4 Congestion Management
When configuring congestion management, go to these section for information that you
are interested in:
Overview

Congestion Management Policy

Configuring an SP Queue
Configuring a WRR Queue
Configuring SP+WRR Queues
Displaying Congestion Management
4.1 Overview
When the rate at which the packets arrive is higher than the rate at which the packets
are transmitted on an interface, congestion occurs on this interface. If there is not
enough storage space to store these packets, parts of them will be lost. Packet loss
may cause the transmitting device to retransmit the packets because the lost packets
time out, which causes a malicious cycle.
The core of congestion management is how to schedule the resources and determine
the sequence of forwarding packets when congestion occurs.
4.2 Congestion Management Policy
Queuing technology is generally adopted to solve the congestion problem. The
queuing technology is to classify the traffic according to a specified queue-scheduling
algorithm and then use the specified priority algorithm to forward the traffic. Each
queuing algorithm is used to solve specific network traffic problems and affects the
parameters such as bandwidth allocation, delay and delay jitter.
The following paragraphs describe strict-priority (SP) queue-scheduling algorithm, and
weighted round robin (WRR) queue-scheduling algorithm.
1) SP queue-scheduling algorithm
Chapter 4 Congestion Management
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