Ok, so my father found lately program which is used by him to checking if my computer is turned on. I wish he wouldn't be able to do that, what can i do about it? Both computers are connected to LAN. Thanks in advance.
just an addition... if you are using windows xp, you can disable the icmp incoming echo request (used for ping) at the control panel > network and internet connections > windows firewall. On the advance tab, click the icmp settings then disable the incoming echo request.