Dell POWERCONNECT 5548P - Dscp Mapping

Dell PowerConnect 55xx Systems User Guide 681
FILE LOCATION: C:\Users\gina\Desktop\Checkout_new\Maintenance Projects\Dell
Contax\CxUGQoS.fm
DELL CONFIDENTIAL – PRELIMINARY 9/11/12 - FOR PROOF ONLY
a Single Policer — Create a policy that associates a class map with a
single policer in the
Policy Table pages and the Class Mapping pages.
Within the policy, define the single policer.
b Aggregate Policer — Create a QoS action for each flow. This action
sends all matching frames to the same policer (aggregate policer),
defined in the
Aggregate Policer pages. Create a policy that associates
a class map with the aggregate policer in the
Policy Table pages.
6 Bind the policy to an interface in the Policy Binding pages .
DSCP Mapping
When a policer is assigned to a class map (flow), you can specify the action to
take when the amount of traffic in the flow(s) exceeds the QoS-specified
limits. The portion of the traffic that causes the flow to exceed its QoS limit
is referred to as out-of-profile packet
s .
If the exceed action is Remark DSCP (as opposed to Drop), the switch
rewrites the original DSCP value of the out-of-profile IP packets to a new
value, based on the values entered in the DSCP Mapping page. The switch
uses the new values to assign resources and egress queues to these packets.
The switch physically replaces the original DSCP value in the out-of-profile
packets with the new DSCP value.
To use the Remark DSCP exceed action, set the DSCP Out value in the
DSCP Mapping page. Otherwise the action is null, because the DSCP value
in the packet is rewritten to the original DSCP value, set by factory default.