A New Path to Moving Faster: Comcast’s ‘RDK’


redlines to instant grimace for cable
engineers is this: Why does it take
so long to get new TV services to

Lots of reasons, but this week’s
translation will hone in on the silicon
part of the equation. Right now,
after an MSO asks for new features
at the silicon level, they wait for
samples. After that, they wait, for
those chips to be built into boxes.
Then, they wait as those boxes get loaded with
developmental code.

Then, the waiting ensues for
middleware stacks, followed by more waiting for
the new service — whatever it is — to be written or
modified to run.

It’s a lot of waiting. From start to finish, the process
can take as long as two years. And that’s if
everything goes well. “Too long, too long,” everyone
mutters — technologists included.

That’s why Comcast is taking a different approach,
quietly launching what it calls “RDK” — for
“Reference Development Kit” — so that systemon-
a-chip (SOC) providers (think Broadcom, Intel,
and their ilk) can spin “cable-ready” silicon.

The intent is to shave as much as a year off the
time it takes to launch a new set-top or gateway.
How? By starting the work of porting before the
chip samples even come back from the factory,
then quickly preparing a reference platform box,
then moving to development. Weeks, not months.

Broadcom described its plans to support the
RDK in a January announcement: “The Comcast
RDK is a pre-integrated software bundle that powers
Tru2way, IP or hybrid set-top boxes … developers
using Comcast’s RDK can create rich, multiscreen
TV home experiences.”

It’s happening now. The RDK will be aboard
Broadcom’s BCM7425 chip; it is already on board
the Intel “Groveland” chips being used in the
MSO’s “Parker” boxes, rolling out in Augusta, Ga.

What’s in the RDK? Lots of stuff. The short list:
A CableLabs “Reference Implementation” (RI) for
OCAP and Tru2way, Java Virtual Machine (JVM), video
proxy, Gstreamer (a video pipeline framework),
QT/webkit (a windowing and browser framework),
and support for optional items like Adobe Flash,
Microsoft’s Smooth Streaming HD and DTCP (Digital
Transmission Content Protection).

In software-speak, the RDK is not unlike a Linux
“distro” (distribution) — a bundle of source code,
drivers, and objects piled into an SOC to help
manufacturers (and operators) get to market more

The RDK follows a “community source” model,
which means anyone who licenses the RDK is obligated
to feed any improvements or bug fixes to all
other licensees. (Yes, this is a cable first.)

How much? It’s royalty-free to chip and hardware
manufacturers, as well as other service providers
that may want to use it.

Watch for RDK and its lingo — SOC, distro, all
of the tech-talk components — to become a much
bigger deal later this year.

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