Quality of Service (QoS): Managing Bandwidth More Effectively  
Using QoS Classifiers To Configure QoS for Outbound Traffic 
Figure 6-10.  Example of Configuring and Listing 802.1p Priority Assignments for 
Packets Carrying Specific IP Addresses 
Assigning a DSCP Policy Based on IP Address 
This option assigns a previously configured DSCP policy (codepoint and 
802.1p priority) to outbound IP packets having the specified IP address (either 
source or destination). That is, the switch: 
1.   Selects an incoming IPv4 packet on the basis of the source or destination 
IP address it carries. 
2.   Overwrites the packet’s DSCP with the DSCP configured in the switch for 
such packets, and assigns the 802.1p priority configured in the switch for 
the new DSCP. (Refer to “Differentiated Services Codepoint (DSCP) 
Mapping” on page 6-58.) 
3.   Forwards the packet through the appropriate outbound port queue. 
Note on  On switches covered in this guide, “mixing” ToS DSCP policies and 802.1p 
Combining 
priorities is not recommended. Refer to the Note on page 6-10. 
Policy Types 
For more on DSCP, refer to “Terminology” on page 6-6. 
Steps for Creating a Policy Based on IP Address.  This procedure 
creates a DSCP policy for IPv4 packets carrying the selected IP address 
(source or destination). 
1.   Identify the IP address you want to use as a classifier for assigning a DSCP 
policy. 
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