User's Manual

Chapter 9 Quality of Service (QoS)
B222s User’s Guide
94
DSCP is backward com patible wit h t he t hree precedence bit s in t he ToS oct et so that non- DiffServ
com pliant , ToS-enabled net work device will not conflict wit h t he DSCP m apping.
The DSCP value determ ines t he forwarding behavior, t he PHB ( Per- Hop Behavior) , t hat each packet
get s across t he DiffServ net work. Based on t he m arking rule, different kinds of traffic can be
m ar ked for different kinds of forwarding. Resources can t hen be allocated according to t he DSCP
values and t he configured policies.
DSCP ( 6 bit s) Unused ( 2 bit s)