The University of Barcelona participates in the Eduroam (EDUcation ROAMing) project, which promotes mobility by enabling members of participating academic institutions to access mobile services at partner institutions. Users therefore have access to a virtual work environment with an Internet connection at any Eduroam institution. 

Eduroam or WifiUB. If you doubt between connecting at wifiUB o at Eduroam, you can read this post of BlogTIC, the blog of  the Area for ICT of the University of Barcelona.