This is quite obviously a prank/fake. I have a lot of friends at Newcastle university and from what I've heard their internet connection in halls was massively restricted, sif they'd tell people to wank in their rooms then block porn.
Well, according to a friend in Newcastle, these notices are in every residence. But I agree with you that it looks fake. I asked him if it was a prank, it's the first thing that came to my mind. He answered that he didn't know. Nonetheless, it's still funny.
There was a pic like that circulating around the interneta while ago, only from the University of Michigan with pretty much the same content. So I'd say it's fake or shower masturbation is an international problem at universities.
My uni has alright internet, can usually download at around 10mb/ps if the site allows eg sourceforge, iplayer etc. streaming iplayer was a bit hit and miss but it didn't matter when you could just download episodes near instantly anyway
aparently alot of uni's do it so their inet can be used for research :/
and all the streaming porn sites work fine :D