Quality of Service (QoS): Managing Bandwidth More Effectively

Using QoS Classifiers To Configure Quality of Service for Outbound Traffic

QoS UDP/TCP Priority

QoS Classifier Precedence: 1

When you use UDP or TCP and a layer 4 Application port number as a QoS classifier, traffic carrying the specified UDP/TCP port number(s) is marked with the UDP/TCP classifier’s configured priority level, without regard for any other QoS classifiers in the switch.

Options for Assigning Priority. Priority control options for TCP or UDP packets carrying a specified TCP or UDP port number include:

802.1p priority

DSCP policy (Assigning a new DSCP and an associated 802.1p priority; inbound packets must be IPv4.)

For a given TCP or UDP port number, you can use only one of the above options at a time. However, for different port numbers, you can use different options.

TCP/UDP Port Number Ranges. There are three ranges:

Well-Known Ports: 0 - 1023

Registered Ports: 1024 - 49151

Dynamic and/or Private Ports: 49152 - 65535

For more information, including a listing of UDP/TCP port numbers,

go to the Internet Assigned Numbers Authority (IANA) website at:

http://www.iana.org

Then click on:

Protocol Number Assignment Services

P (Under “Directory of General Assigned Numbers” heading)

Port Numbers

15-14