hello there, I have a question, there are some providers which give wifi access to their customers throughout the city using user name + password If i don't have this service but a friend does and he connects to the internet using his credentials at my place, using my laptop, am I somewhat responsible for what he does? or once removed the cashe there are no more traces? i hope i made myself clear asking this question
There are ways of tracking specific computers when they are connected to the web. IP address, MAC address, what browser was used, what version of operating system and more. That said, unless your friend is doing something illegal, I doubt you have much to worry about. If he is doing something illegal, law enforcement has many ways to catch people. I'd be much more concerned then...
Another simple option would be to have a linux live flash that you can fire up. Everything happens in RAM and the flash could auto change the MAC and stuff. Once you bring down the live linux session everything is completely gone. There would be zero traces of any kind on your laptop and any router logs would show a "foreign" mac. In addition to security concerns it simply keeps your friends from accidentally infecting your machine. I know this sounds like overkill, but I keep this exact thing around for when "family" comes over and wants to check their email, facebook, etc....