Operation Manual – QoS-QoS ProfileH3C S5600 Series Ethernet Switches Chapter 1 QoS Configuration1-9precedence corresponding to the port priority of the receiving port in the 802.1p-to-localprecedence mapping table, and assigns the local precedence to the packet.2) For an 802.1q tagged packetWhen an 802.1q tagged packet reaches the port of a switch, you can use the prioritytrust on the receiving port to configure the port to trust packet priority or use thepriority command on the receiving port to configure the port to trust port priority. Bydefault, port priority is trusted and the priority of a port is 0.z Trusting port priorityIn this mode, the switch replaces the 802.1p priority of the received packet with the portpriority, searches for the local precedence corresponding to the port priority of thereceiving port in the 802.1p-to-local precedence mapping table, and assigns the localprecedence to the packet.z Trusting packet priorityIn this mode, the switch searches for the local precedence corresponding to the 802.1ppriority of the packet in the 802.1p-to-local precedence mapping table and assigns thelocal precedence to the packet.Table 1-5 shows the default 802.1p priority-to-local precedence mapping table. You canmodify the default mapping tables at the CLI. For detailed configuration procedure,refer to Configuring the Mapping between 802.1p Priority and Local Precedence.Table 1-5 802.1p priority-to-local precedence mapping table802.1p priority Local precedence0 21 02 13 34 45 56 67 71.3.3 Protocol PriorityProtocol packets generated by a switch carry their own priority. You can set a new IPprecedence or DSCP precedence for the specific type of protocol packets to implementQoS.
