Sometimes, I cannot go online even though I am connected to the WiFi network. The cables are connected properly, restarting the WiFi router or computer does not help.

This usually happens when my roommate is at home and skyping with friends. When I complain, which I cannot do until he is done skyping, it miraculously works again.

Can he intentionally block my internet connection?

Also, how can I find out whether he is “listening” to my network traffic. Specifically, I want to find out how I can block him from reading my eMails or seeing what websites I browse. Being my roommate he knows the WiFi password and has physical access to my computer.

He has mentioned using spybuddy.com on his friends, which reinforced my previous suspicion that he somehow intercepts my internet connection.

I run Windows XP on a laptop. I have the login data for the WiFi router and could change the settings.

Yes, I will be moving out, but I cannot move out until December 1st, so I need a solution for the meantime. Thank you very much in advance!