There are many ways to do this probably the easiest is to set up your local vi for control to publish to the web. This is under tools->publish to the web. Other code based methods are to set up client server architectures like TCP/IP or data sockets.
You could configure the host computer to use VISA Server, then access the instrument as if it was connected to your computer at home.
The concept is simple, but things like firewalls, routers and port number filtering often get in the way when trying to do this sort of thing over the internet.
