4-3z Forwarding the traffic if the evaluation result is “conforming.”z Dropping the traffic if the evaluation result is “excess.”z Marking a conforming packet or a non-conforming packet with a new DSCP precedence value andforwarding the packet.Traffic ShapingTraffic shaping provides measures to adjust the rate of outbound traffic actively. A typical traffic shapingapplication is to limit the local traffic output rate according to the downstream traffic policing parameters.The difference between traffic policing and GTS is that packets to be dropped in traffic policing arecached in a buffer or queue in GTS, as shown in Figure 4-2. When there are enough tokens in the tokenbucket, these cached packets are sent at an even rate. Traffic shaping may result in an additional delaywhile traffic policing does not.Figure 4-2 Schematic diagram for GTSTokenbucketPackets droppedPacketclassificationPackets to be sentthrough this interfacePackets sentTokens are put into thebucket at the set rateQueueFor example, in Figure 4-3, Switch A sends packets to Switch B. Switch B performs traffic policing onpackets from Switch A and drops packets exceeding the limit.Figure 4-3 GTS applicationYou can perform traffic shaping for the packets on the outgoing interface of Switch A to avoidunnecessary packet loss. Packets exceeding the limit are cached in Switch A. Once resources arereleased, traffic shaping takes out the cached packets and sends them out. In this way, all the trafficsent to Switch B conforms to the traffic specification defined in Switch B.
