Make Free — Selectable Output Control

Home Technology

Chances are, you haven’t heard of “selectable output control” (SOC), a proposed digital TV technology that would allow broadcasters to tag their content with a list of devices that are allowed to play it. That’s because it’s an insane idea.

Picture this: you power up your home theater, a complex network of game consoles, A/V switchers, cable boxes, PVRs, DVD players, 5.1 speakers, amps, a home theater PC, and a monitor or projector. After locating the correct remote, you start surfing through channels. All good. But when you hit MTV, the gorgeous, perfectly balanced sound stops.

Why? Because MTV doesn’t want you digitizing the songs that accompany its music videos, so it sends a digital “flag” that disallows high-end audio on equipment that doesn’t contains digital rights management (DRM). Your beautiful hand-built tube amp certainly isn’t compatible, so if you want sound while watching MTV, you’ve got to turn on the tiny internal speakers that came with your TV.

You surf on up the dial (get up again and turn off the internal speakers), and flip to HBO. Your screen goes dark. That’s because HBO is showing a movie that has been flagged as “no analog” — which means your beautiful 42″ plasma display won’t work because you connected it via the composite analog video cables coming off the back of your A/V switcher, rather than via the DRM-locked HDMI output.

To watch the movie, you’ll need to move the entire shelving unit (remember to take down the family photos first, doofus, otherwise you risk shattering the glass if they tip over), disconnect the analog cables, dig around in the garage to find the HDMI cable that came with the TV (or was it the cable box?), and rewire your set.

One more channel up the dial and the screen goes dark again. Google around for a while, and you discover that some kid in the Ukraine published a class break last month for HDCP, the anti-copying crap in HDMI, that makes it possible to record HDCP content using “unauthorized” technology. So here on Showtime, they’ve restricted HDCP as well as analog. You’re going to need DVI for this one. You grab a little Maglite and peer hopefully at the inputs on the plasma. No DVI. Now what? Buy a new TV?

This is where SOC crosses the line from totally objectionable to totally insane. With SOC, it doesn’t matter if you’re careful to buy only “approved” technologies and set them up in the “approved” manner. Because no matter how you set your stuff up today, the signal can be altered to prohibit access tomorrow, if someone, somewhere, figures out how to do something naughty with a device you have the misfortune of owning.

You haven’t heard of SOC because, in 2003, the FCC told broadcasters and cable operators that they weren’t allowed to use it. But, like a bad Hollywood sequel, it’s back. The Motion Picture Association of America has petitioned the FCC for the right to turn on SOC for new-release movies.

It promises it won’t use SOC for other purposes, but you can bet its use will expand and expand.

SOC isn’t just a cable proposal, it’s an entire philosophy that’s the antithesis of making. It’s a philosophy that says that the dead hand of the original manufacturer will be an immortal presence in every device you own, yanking out the wires that it objects to, turning the dials to suit its needs. If you’ve ever done something with a device that the manufacturer didn’t intend (or wouldn’t like), you can appreciate how bad an idea this is.

Copyright has its place. I think that it’s totally legit to propose that someone who makes a creative work should be allowed to control the circumstances under which companies can sell copies of it. But since when does copyright give a creator the right to tell you which wires to plug into your TV?

The Electronic Frontier Foundation — which fought SOC in 2003 — is fighting it again, and you can help out at

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Cory Doctorow

Cory Doctorow ( is a science fiction author, activist, and journalist.

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