H3C H3C S5100-SI, Operation Manual, Page: 401 / 830

1-12
Table 1-10 The default DSCP-precedence-to-DSCP-precedence mapping table of
S5100-SI/EI series switches
DSCP value Target DSCP value
0 0
1 1
2 2
3 3
... ...
61 61
62 62
63 63
Protocol Priority
Protocol packets generated by your switch carry their own priority. You can set a new IP
precedence or DSCP value for the locally generated traffic of a particular protocol to
implement QoS.
Priority Marking
The priority marking function is to reassign priority for the traffic matching an ACL
referenced for traffic classification.
z
If 802.1p precedence marking is configured, the traffic will be marked with the local
precedence value corresponding to the re-marked 802.1p precedence value and
assigned to the output queue corresponding to the local precedence value.
z
If DSCP marking is configured, the traffic will be marked with the new DSCP value.
Traffic Policing and Traffic Shaping
If user traffic is not limited, burst traffic will make your network more congested. To better
utilize the network resources and provide better services for more users, you must take
actions to control user traffic. For example, you can configure a flow to use only the
resources committed to it in a time range, thus avoiding network congestion caused by
burst traffic.
Traffic policing and traffic shaping limit traffic rate and resource usage according to traffic
specifications. The prerequisite for traffic policing or traffic shaping is to know whether a
traffic flow has exceeded the specification. If yes, proper traffic control policies are applied.
Generally, token buckets are used to evaluate traffic specifications.