The Slingbox has two basic components. The Slingbox (server) and the Slingplayer (client). The Slingbox is the component that transcodes baseband signals into a multimedia format that can be broadcasted over the network. The Slingplayer allows you to watch the content streaming from the Slingbox. The Slingplayer is available on different operating systems for many different devices.
The Slingbox would be connected to your father's set-top box, like a satellite receiver, cable box. The connections are supported by baseband connectors (Left & Right Audio, Composite, Component, S-Video, or Coax). The Slingbox has IR blasters which need to be positioned to the set-top box's IR sensor in order to support controlling it from the Slingplayer client.
One of the important aspect of live streaming is the bandwidth between both points. The location where the Slingbox resides will require sustained upload bandwidth. The location where the Slingplayer resides needs the sustained download to be met. You should note, that most broadband providers and broadband test sites will promeniant display download burst speeds, since that's always the biggest number. However, when streaming it is important that each site is able to maintain the the sustained speeds. You'll need 3 Mbps or higher for HD Streaming, 600 Kbps or higher for SD streaming, and 150 Kbps or higher for Mobile Streaming.
There's more information here (http://www.slingbox.com/go/slingbox-prohd-techspecs)