The sender unit has an hdmi input, and the receiver has an hdmi output. How's that for simple. OK, there's also an RS232 on each unit. With RS-232 for command and control, you could use RS-232 to power up and down both the sender and receiver units.
Alternately, the pair of units come with a remote control to power them up and down. Guess what, whether by room controller, or remote control, it's worth the trouble to shut them down when not in use. Each unit is rated an 18 watt draw. That 36 watts total, which adds up to a fair amount of kilowatts if you let them run 24/7. Out here in LA LA land, I figure that's about $60 a year and change. One more item to add to a programmable remote, room controller, PC, or, use the provided remote.
I'm pleased, from a practical standpoint, the Gefen hdmi wireless solution performs as advertised. I'll be adding this to my equipment in my main theater, as it solves a long standing, real problem, and does so, without any real issues.
Gefen also offers two other HDMI wireless extenders - however neither are lossless, and therefore were not of particular interest to me. One, though, of note, claims a range of 100 feet, and has a multi-room option. That one is the somewhat similarlynamed: GTV-WHDMI, not to be confused with this one, the GTV-WirelessHD.