Eduroam stands for Education Roaming which is a federation of institutions that offers Internet connectivity to the roaimng users of all other member institutions. This is done by accepting the credentials from the user's home institution through a RADIUS hierarchy.
Eduroam initially started as a European initiative, but become international over the time. The list of participanting countries and for further information go to http://www.eduroam.org.
Eduroam in Hungary also built on a hierarchical manner, using RADIUS proxies, with a top-level operated and coordinated by NIIFI. NIIF become a member of the eduroam confederation since the beginning of 2006.
The Hungarian eduroam site: