Operation Manual – QoS-QoS ProfileH3C S5600 Series Ethernet Switches Chapter 1 QoS Configuration1-31.1.4 Major Traffic Control TechniquesFigure 1-1 End-to-end QoS modelAs shown in the figure above, traffic classification, traffic policing, traffic shaping,congestion management, and congestion avoidance are the foundations for a networkto provide differentiated services. They are described as follow:z Traffic classification identifies traffic based on certain matching rules. It is aprerequisite for differentiated services and is usually applied in the inbounddirection of a port.z Traffic policing confines traffic to a specific specification and is usually applied inthe inbound direction of a port. You can configure restriction or penalty measuresagainst the exceeding traffic to protect carrier benefits and network resources.z Traffic shaping adapts output traffic rate usually to the input capability of thereceiving device to avoid packet drop and port congestion. Traffic shaping isusually applied in the outbound direction of a port.z Congestion management handles resource competition during networkcongestion. Generally, it adds packets to queues first, and then forwards thepackets by using a scheduling algorithm. Congestion management is usuallyapplied in the outbound direction of a port.z Congestion avoidance monitors the use of network resources and drops packetsactively when congestion reaches certain degree. It relieves network load byadjusting traffics. Congestion avoidance is usually applied in the outbounddirection of a port.Traffic classification is the basis of all the above-mentioned traffic managementtechnologies. It identifies packets using certain rules and makes differentiated servicespossible. Traffic policing, traffic shaping, congestion management, and congestionavoidance are methods for implementing network traffic control and network resourcemanagement. They are occurrences of differentiated services.
