Say you have found out the ISP of a person and simply want to learn as to in which country the person resides in. However, visiting the ISP website doesn’t help. Nor does the hostname help. So, what do you do? Well, one thing that you could do is, try connecting to Port 13 of the ISP. This is the port, which simply displays the system time. It will tell you how many hours ahead or behind the system is from GMT time.
