Operation Manual – QoS-QoS ProfileH3C S5600 Series Ethernet Switches Chapter 1 QoS Configuration1-5QoS Feature Description Refer to …CongestionmanagementThe S5600 series support SP andWRR queue scheduling algorithmsand support the following threequeue scheduling modes:z SPz WRRz SP+WRRFor information aboutSP and WRR, refer toQueue Scheduling.1.3 Introduction to QoS Functions1.3.1 Traffic ClassificationTraffic here refers to service traffic; that is, all the packets passing the switch.Traffic classification means identifying packets that conform to certain characteristicsaccording to certain rules. It is the foundation for providing differentiated services.In traffic classification, the priority bit in the type of service (ToS) field in IP packetheader can be used to identify packets of different priorities. The network administratorcan also define traffic classification policies to identify packets by the combination ofsource address, destination address, MAC address, IP protocol or the port number ofan application. Normally, traffic classification is done by checking the informationcarried in packet header. Packet payload is rarely adopted for traffic classification. Theidentifying rule is unlimited in range. It can be a quintuplet consisting of source address,source port number, protocol number, destination address, and destination port number.It can also be simply a network segment.1.3.2 Priority Trust ModeI. Introduction to precedence types1) IP precedence, ToS precedence, and DSCP precedenceFigure 1-2 DS field and ToS byteThe ToS field in an IP header contains eight bits numbered 0 through 7, among which,
