ZyXEL P-870HN-51b User Guide - Page 212
IP Precedence, Automatic Priority Queue Assignment, PRIORITY, QUEUE, LAYER 2, IEEE 802.1P
View all ZyXEL P-870HN-51b manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 212 highlights
Chapter 16 Quality of Service (QoS) different kinds of traffic can be marked for different kinds of forwarding. Resources can then be allocated according to the DSCP values and the configured policies. IP Precedence Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a layer-3 network. IP precedence uses three bits of the eightbit ToS (Type of Service) field in the IP header. There are eight classes of services (ranging from zero to seven) in IP precedence. Zero is the lowest priority level and seven is the highest. Automatic Priority Queue Assignment If you enable QoS on the Device, the Device can automatically base on the IEEE 802.1p priority level, IP precedence and/or packet length to assign priority to traffic which does not match a class. The following table shows you the internal layer-2 and layer-3 QoS mapping on the Device. On the Device, traffic assigned to higher priority queues gets through faster while traffic in lower index queues is dropped if the network is congested. Table 76 Internal Layer2 and Layer3 QoS Mapping LAYER 2 LAYER 3 PRIORITY QUEUE 0 1 2 3 IEEE 802.1P USER PRIORITY (ETHERNET PRIORITY) 1 2 0 3 TOS (IP PRECEDENCE) DSCP 0 000000 0 000000 1 001110 001100 001010 4 4 001000 2 010110 010100 010010 5 5 010000 3 011110 011100 011010 011000 IP PACKET LENGTH (BYTE) >1100 250~1100