I have wifi internet. Ok, frequently this has been happening. I come home and awake my Mac up and find that my AirPort and therefore my internet is not connected. I have to put my Wep Key to reconnect only for it to time out. The only way I can connect back on to the internet is my shutting down my Mac, turning off and On my Router and turning back on my Mac. When it boots up I'm back on line. What can this be?