COM2TCP

COM2TCP and TCP2COM are applications that allow you to tunnel a serial connection over a network. Although they were designed for remote telescope operation, they can be used to remotely control virtually any serial device.
The diagram below shows TCP2COM being run on computer and connected to a telescope hand controller.

COM2TCP is run on another computer -- on the other side of the house or the other side of the world -- and connects over a network in order to control the telescope from afar.