H3C S7500E Series Operation Manual page 1006

Operation Manual – QoS
H3C S7500E Series Ethernet Switches
Congestion management: Congestion management is necessary for solving
resource competition. Congestion management is generally to cache packets in
the queues and arrange the forwarding sequence of the packets based on a
certain scheduling algorithm.
Congestion avoidance: Excessive congestion will impair the network resources.
Congestion avoidance is to supervise the network resource usage. When it is
found that congestion is likely to become worse, the congestion avoidance
mechanism will drop packets and regulate traffic to solve the overload of the
network.
TS: TS is a traffic control measure to regulate the output rate of the traffic actively.
TS regulates the traffic to match the network resources that can be provided by the
downstream devices so as to avoid unnecessary packet loss and congestion.
Among the traffic management techniques, traffic classification is the basis because it
identifies packets according to certain match rules, which is the prerequisite of
providing differentiated services. TP, TS, congestion management, and congestion
avoidance control network traffic and assigned resources from different approaches,
and are the concrete ways of providing differentiated services.
1-4
Chapter 1 QoS Overview