Application Scenarios for Traffic Policing, Traffic Shaping, and Interface-based Rate Limiting
Traffic Policing
As shown in Figure 5-7, voice, video, and data services are transmitted on a data center network. When a large amount of traffic enters the network, congestion may occur due to insufficient bandwidth. Different bandwidth guarantees must be provided for the voice, video, and data services, listed in descending order of priority. In this situation, traffic policing can be configured to provide the highest guaranteed bandwidth for voice packets and the lowest guaranteed bandwidth for data packets. This configuration ensures preferential transmission of voice packets when congestion occurs.
Traffic Shaping
On a data center network shown in Figure 5-8, multiple interfaces of SwitchB connect to computing servers, and multiple interfaces of SwitchC connect to web servers. When a user sends a search request, the computing servers perform distributed computing and send the result to the corresponding web server through SwitchA. Then the user obtains the search result from the web server. When the computing servers compute a large amount of data, the heavy traffic sent to the web servers causes inbound traffic bursts on SwitchA. As a result, congestion may occur in the outbound direction on the interface of SwitchA connected to SwitchC. Traffic shaping can be configured in the outbound direction on this interface to transmit burst traffic evenly to the web servers.
Interface-based Rate Limiting
Voice, video, and data services are transmitted on an enterprise network. When a large amount of traffic enters the network, congestion may occur due to insufficient bandwidth. The rate of traffic entering the network needs to be limited. As shown in Figure 5-9, interface-based rate limiting is configured on the inbound interface of SwitchB to limit the inbound traffic rate. Excess traffic will be discarded.
