Linux Ubuntu

First step: is your driver installed?
To discover what card you have:

Second step: install the NetworkManager.
sudo apt-get install network-manager
The icon should appear in the notification area (somewhere near the clock). Select it by right button and ensure yourself you have the "allow wireless" ticked. Then select it with left button and you should see all the sites broadcasted in your area. Select "eduroam" an the dialog should appear.

Third step: download the certificate of STU Bratislava CA
I downloaded the pem certificate on this site:

Fourth step: connect to site dialog.
Remember the dialoge that appears by selecting the eduroam site in the networkmanager? Please fill it by the picture attached.
name: eduroam,
wireless security: wpa enterprise,
eap method: peap,
key type: tkip,
identity: Tato adresa je chránená proti spamovaniu, pre jej zobrazenie potrebujete mať Java scripty povolené ,
password: *****

anonymous identity: don't fill,
client certificate: none,
ca certificate: stu_ca.cer,
private key file: none,
private key password: don't fill

Fifth step: you should be logged into the site
and recieve the ip adress by the dhcp server. It's simple