Today I connected to a public network at university. This network apparently only allows connections to sites that https protocol. Every connection to http sites was denied. For example, that way I was able to google but not able to visit the resulting sites. Can this connection limitation be network-imposed or does it have something to do with the settings of my computer? If yes; how / where can I change these settings. At home I have no trouble visiting http websites.

I'm using Ubuntu 12.04. (Gnome). If it is of any relevance: the wireless network is called "IMAC x", therefore it may originate from an Imac computer and not a proper router.