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Inside the Comcast RDK, Part Two

This week’s Translation 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-Internet protocol hardware and services.

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 “now-and- 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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