Dahua DH-PFS4212-8GT-96 Web Operation Manual page 48

poor control of the arrived flow in a certain time, which leads to the flow exceeding the distributive
network resource, is also a factor for generating congestion.
3.2.6.1 Port
Through setting CoS, the priority for packet passing egress port of switch can be decided.
If the congestion occurs at the egress port, the switch will give a CoS value to the packet after it
passes the ingress port. The larger the CoS value, the higher the priority.
Select Advanced > Seldom-used > QoS > Port Classification.
Step 1
Step 2 Set CoS. For example: Set port 1 to be 1, and port 2 to be 2. See Figure 3-54.
Port 1 and port 2 are ingress ports, and port 3 is egress port. The CoS value of port 2 is large
than that of port 1, so the data of port 2 will pass port 3 first.
Figure 3-53 Port classification
42