How to protect printer from others

Hi there,
I've got an HP Printer which supports ePrint, which is very useful for me because I always need to print stuff, especially when i'm at college.
The only problem is: we've got almost 200 people on the same network here. And I don't want radom trolls to just be able to print with my printer. (The printer has a direct wired connection to the network)
Is there any way to do this?

Thanks :)
ShadowAS1