Planet ISW-802M User Manual page 45

TOS first: the port priority will follow the TOS priority first, and the other priority rule.
COS priority: set the COS priority level 0~7.
TOS priority: the system provides 0~63 TOS priority level. Each level has 4 type of priority - high,
mid, low, and lowest. The default value is "Lowest" priority for each level. When the IP packet is
received, the system will check the TOS level value in the IP packet that has received. For example:
user set the TOS level 25 is high. The port 1 is following the TOS priority policy only. When the
packet received by port 1, the system will check the TOS value of the received IP packet. If the TOS
value of received IP packet is 25(priority = high), and then the packet priority will have highest
priority.
QoS and Rate control cannot be existed at the same time.
[NOTE]