The ‘Virtualization’Of the Set-Top Box

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 settop
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

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
: “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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