The ‘Virtualization' Of the Set-Top Box

Last week, we examined the reasons why the local headend isn’t on the endangered species list. This week, the other end of the spectrum: the set-top box.

Not that set-tops are headed for extinction anytime soon. More that the functionality of the digital set-top box shows every sign of being “virtualized” - another term drifting into the cable tech scene from the cloud scene with increasing regularity.

Cable engineers and technologists whose work dates back to the early days of “converters” (the original name for what we now call set-tops) are quick to point out that it isn’t as though the industry woke up one day and decided that what televisions needed were big ugly boxes perched somewhere nearby.

Then and now, set-tops existed to provide features that weren’t happening elsewhere. Way back at the beginning, they cured a problem called “multipath” reception. Those early TVs, back in the analog-only days, lacked sufficient shielding around various parts - the tuner inside and the antenna terminals on the back of the TV, to be specific. As a result, when you were watching a local channel, more often than not you’d see a ghosted image next to the intended image. Converters fixed that.

Soon after, and as cable channels began to proliferate, converters were needed so that the knob on the television could tune above channel 13.

As premium cable channels surfaced in the mid- 1970s, so did the need to secure them. Enter the “set-top descrambler” box.

Then came the remote control, to tune channels from the comfort of the couch, instead of (gasp!) getting up and walking over to the TV. Cable offered remotes long before TVs did.

And so on, through parental controls, addressability (so that service turn-on and turn-off could happen without rolling a truck), favorite channels and on-screen program guides. And that’s all before digital.

Fast-forward to now. Digital brought way more channels, high definition, video-on-demand, timeshifted television, closed captioning and the dozens of other features we tend to take for granted. (Until you sample the over-the-top video variants.)

“Virtualization” recreates those features - but in software, not plastic. So says the Oxford English Dictionary: “Not physically existing as such but made by software to appear to do so, from the point of view of the program or user.”

In a set-top sense, virtualization will encapsulate those features and functions into blobs of code, which can be instantiated on other devices - TVs, tablets, screens that want to be TVs and gateways to other screens.

The pessimist’s view: Set-tops are dead, finally, hurrah. The optimist’s: Set-tops are becoming “soft” set-tops, which vastly extends their reach, while reducing the physical clutter near the screen.

The truth is usually somewhere in the middle.


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