Dell PowerConnect 5212 System User's Manual page 65

The DSCP value is six bits wide, allowing coding for up to 64 different forwarding behaviors. The DSCP value replaces the ToS bits, and it retains backward
compatibility with the three precedence bits so that non-DSCP compliant, ToS-enabled devices, will not conflict with the DSCP mapping. Based on network
policies, different kinds of traffic can be marked for different kinds of forwarding.
In the IP DSCP Priority section, you can map DSCP values to traffic class values. These settings apply to all ports on the switch.
The following options are available:
DSCP Priority Table — Displays a list of DSCP values mapped to CoS values.
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Class of Service Value — Sets a new CoS for a DSCP value. The number 0 represents low priority and 7 represents high priority.
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Click IP DSCP in the IP Precedence/DSCP Priority Status field to enable this feature.
Each IP DSCP value (from 0 to 63) is mapped to one CoS value (from 0 to 7). The number 0 represents the lowest priority and 7 represents the highest
priority.
The following table shows the default priority mapping. All of the DSCP values that are not specified are mapped to CoS value 0.
IP DSCP Value CoS
Value
0 0
8 1
10, 12, 14, 16 2
18, 20, 22, 24 3
26, 28, 30, 32, 34, 4
36
38, 40, 42 5
48 6
46, 56 7
To change a table setting, select the entry in the DSCP Priority Table, type the new CoS value in the Class of Service Value box, and then click Apply
Changes. If you don't want to save the changes, click Refresh.
CLI Commands
The following table summarizes the equivalent CLI commands for items in the Class of Service/IP Precedence web page.