Mounting a Network drive without losing it.....

well, every time i put my computer to sleep the shared network drive loses connection and i have to connect manually.
Also, when i am on the university network, it disconnects as well.

Is there any way I can keep my disk drive mapped all the time- like in windows where its always mapped(but not accessible) even if you are on a different network......

It's a pain in the ass to keep mounting the drive every time I come back from the university!!!