Hi there,
This is quite simple to setup.
The link below shows you how to authenticate users to the local WLC database (manual entries) or authenticate them against RADIUS servers (AD for example).
http://www.cisco.com/c/en/us/support/docs/wireless-mobility/wlan-security/69340-web-auth-config.html
Otherwise you can use the 'Passthrough' method which doesn't require credentials to access the network. The portal can be displayed on the WLC or an external web server.
http://www.cisco.com/c/en/us/support/docs/wireless/4400-series-wireless-lan-controllers/107474-web-pass-config.html
Regards,
Brett
