Quality of Service (QoS): Managing Bandwidth More Effectively 
Using QoS Classifiers To Configure Quality of Service for Outbound Traffic 
Assigning an 802.1p Priority Based on TCP or UDP Port 
Number 
This option assigns an 802.1p priority to (IPv4)  TCP or UDP packets as 
described below. 
Syntax:  qos < udp-port | tcp-port > < tcp or udp port number > priority < 0 - 7 > 
Configures an 802.1p priority for outbound packets 
having the specified TCP or UDP application port 
number. This priority determines the packet’s queue in 
the outbound port to which it is sent. If the packet leaves 
the switch on a tagged port, it carries the 802.1p 
priority with it to the next downstream device. 
(Default: Disabled) 
Note: On 3400cl/6400cl switches, this feature is not 
supported for IPv4 packets with IP options. For more 
information on packet-type restrictions, refer to table 
8-15 on page 8-70. 
no qos < udp-port | tcp-port > < tcp-udp port number > 
Deletes the specified UDP or TCP port number as a QoS 
classifier. 
show qos tcp-udp-port-priority 
Displays a listing of all TCP and UDP QoS classifiers 
currently in the running-config file. 
For example, configure and list 802.1p priority for the following UDP and TCP 
port prioritization: 
TCP/UDP Port  802.1p Priority 
for TCP 
802.1p Priority 
for UDP 
TCP Port 23 (Telnet) 
7  7 
UDP Port 23 (Telnet) 
7  7 
TCP Port 80 (World 
2  2 
Wide Web HTTP) 
1 1
UDP Port 80 (World 
Wide Web HTTP) 
8-25