ethernet connection goes on and off

ethernet goes on and off... when i go to system preference to see networks, ethernet comes green and then red, green then red... at a pretty fast rate.

does the same for my other powerbook... so im guessing its something with the modem for this college apartment?! any ideas how to fix it or suggestions?

Thanks

Is the modem or router provided by your college along with the apartment? If so, ask them to help you configure it or replace it if it's defective. If it's your modem, go over the manual and make sure it's setup correctly. Also, if you're hooked directly to the modem without a router, that limits the distance you can be from the modem itself. A wireless router hooked from the modem would be more convenient to use.

Regards.