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Inside the ComcastRDK, Part Two

steps further into the
parts of the Comcast
“RDK” (reference development
kit), the software
effort aimed at shaving
a year off the time it
takes to launch new
cable gateways, hybrid
set-tops and all-Internetprotocol
hardware and

Quick refresher: RDK is a bundle of
software drivers and source code that gets
preloaded into chips so manufacturers can
develop product more quickly. That means
apps, services and everything related goes
more quickly. Quickly is the goal of RDK.

In essence, the RDK outlines a “nowand-
next” list of software items, where
“now” means what’s in today’s digital
set-tops: A CableLabs “Reference Implementation”
(RI) for OCAP and Tru2way, a
Java Virtual Machine (JVM), a video proxy,
media streamer and DTCP (Digital Transmission
Copy Protection), for security.

The “next” parts of the RDK come from
the IP (Internet-protocol) side of the world.

Recall that a huge driver for the RDK is
to tap into the larger world of Internet developers
instead of building complicated,
cable-specific stuff.

For brevity, we’ll sidestep the familiar,
“how things are now” components, which
this column has covered every which way
over the past decade.

Let’s look instead at the new stuff:
Gstreamer, QT and webkit. We’ll start
with “QT,” which people tend to say as a
word: Cute. (No, really.) QT is a “windowing
framework,” meaning it’s the traffic cop for
everything that wants to get onto a screen.

And because nearly everything in software
happens in stacks, the next one up
in RDK is “webkit,” a browsing framework
used under the hood of Safari, Chrome,
and mobile environments like iOS (Apple)
and Android (Google).

Including a browsing framework,
notably, isn’t the equivalent of Internet
browsing on TV. Rather, a browser
framework knows how to do things like
render HTML, parse incoming markup
languages and access specific media
types — so that a browser, as we know
it, could work on top of it.

Then there’s Gstreamer — and here
comes that “framework” again, this time
for video. It’s what’s underneath the processing
or raw audio and video files, so
that they play out as intended. Handily, it’s
a framework that plugs into multiple types
of digital rights management (DRM).

In the olden days of right now, most of
these activities are done on proprietary silicon
that works differently, one chip vendor
to the next. RDK exists to change that.

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