Hi Mohamed,

Just to add a note to the good tip from Andrew (+5 points Andrew :)

I have searched high and low and have spoken with some experts about the Utility Interface and all they can tell me is that it is reserved for "Future" use and serves absolutely no function at this time.

Here is the relevant clip;

"Note: Figure 3-2 shows a Cisco 4404 controller. The Cisco 4402 controller is similar but has only two distribution system ports. The utility port, which is the unlabeled port in Figure 3-2, is currently not operational."

Cisco Wireless LAN Controller Configuration Guide, Release 5.0

Configuring Ports and Interfaces

http://www.cisco.com/en/US/docs/wireless/controller/5.0/configuration/guide/c5mint.html#wp1113882

Hope this helps!

Rob