Death of a Cable Box
2025-11-28
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My parents love watching television. For many years, they had almost ten TVs scattered around their house, some dating back to the 1980s. Having televisions that old required them to use a service that sent signals directly over coaxial, without requiring a cable box. That became tough to find by the late 2010s, and in 2022, the last such service in their area switched to IPTV. My parents eventually changed providers and now rely exclusively on set-top boxes.
The former provider never asked for the cable box to be returned, since it was now useless. A few weeks ago, as I was helping to clean out my parents' garage, we found the box and its remote control. The box had a hard drive inside, and back in the day, they had recorded several hours of programs on the box. I offered to take it home and try to extract the recorded data.
To my dismay, I discovered that the box uses two layers of encryption to save the recorded data. One layer is provided by a Cisco PowerKEY installed in the box. I extracted the key for possible later use in a PC to decrypt the hard drive, thinking that was all I would need.
The second layer of security comes from keys sent by the provider to the box over the wire in real time. If the customer disconnects from the service, keys don't arrive on the box, and the hard drive's contents can't be decrypted. As the company in question doesn't even offer the type of service needed to connect the box again, the data on the hard drive is now useless.
However, another problem exists. It turns out that even if I had the necessary connection and the right PowerKEY to decrypt the content, I still wouldn't be able to do it due to a bug in the original Scientific Atlanta system. The hardware clock rolled over in November 2024, causing a time mismatch that blocked decryption on the cable box. The only widespread solution to the problem was to replace the affected boxes, which of course never happened in my parents' case.
The extent to which data like this is locked down annoys me. I know TV shows are copyrighted, and I didn't expect decryption to be easy. But with the loss of these recordings, we lose various ephemera like local broadcasts and memorable commercials. There's a reason why I prefer more open platforms--or, at the least, platforms from which yt-dlp can archive data.
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[Last updated: 2025-11-28]