Digital Hubbub

It's a set-top! It's a home server! It's a digital hub! Whatever you call it—a souped-up cable box or a hard-disk recorder with wings—companies know that whoever gets it right will rule the entertainment gateway to the home.

More than a half-dozen companies so far are scrambling for the billions of dollars they hope to reap by offering consumers a single machine to handle their home entertainment needs. 7.HomeVideo.f3The companies agree on what the machine should do: record, archive, and play back video and music, organize digital photo albums, and distribute digital media around the home. Where they disagree is on what shape that machine should take.

As might be expected, each company is casting this new species in its own image. To Apple and Microsoft, it looks like a computer. To cable and satellite companies like Charter, Echostar, or DirecTv and their suppliers, it's a set-top box. To consumer electronics companies like Philips or Samsung, it's a stereo component.

Visions abound. Samsung Group (Seoul, South Korea), for example, is betting that some of the people buying high-end DVD players (the overall DVD market almost doubles every year) will gladly pay a few dollars extra for a hard disk that turns their player into a personal video recorder (PVR) while acting as a storage bin for digital photos and audio files ripped from CDs. At the other end of the gamut, Microsoft Corp. (Redmond, Wash.) is pushing utopian schemes of a home controlled by wireless touch screens with computers serving video and audio to any TV or PC screen in the house.

And in a new twist on an old product, some European Linux hackers are working on software that will record and play video and audio using cast-off PCs from the late 1990s. Those who would benefit from this effort are the truly fearless people who can build their own digital entertainment centers by downloading the right code and cobbling together surplus parts.

Just as companies disagree about what kind of device this new convergent gadget may be, they also differ on what to call it. Going for the most generic, for this article IEEE Spectrum will use the expression "digital hub," a term coined by Apple Computer Inc.'s chief executive officer Steve Jobs.

Although digital hubs may be kin under the surface, what they do will differ enormously. Their use depends on the product line they emerge from: computer, video recorder, satellite or cable box, DVD player, or even a game console. While home computer and audio and video systems are finally converging—and sometimes colliding—so are ideas about computer and software architecture, business plans, and intellectual property protection.

In shaping digital home entertainment, several crucial issues must be addressed. How will different pieces of software written by competing companies work together? Who will pay for the digital hubs and put them in homes? Who owns the material stored on a hub's hard disk, and who, legally, can control how it is transferred and displayed?

The hub as factotum

Whatever their genesis, the functions that the digital hubs provide are similar. Virtually all will record video and audio and store still photos from various sources, including your personal CD library, broadcast TV, and the Internet. They will also be able to store and play video games. And they will organize all your media files in an easy-to-browse fashion and play them back on demand, making available such features as pause, rewind, and several varieties of skip and fast-forward.

Typically, a hub might incorporate a high-capacity hard-disk drive, a CD/DVD player, a TV tuner, and inputs for digital cameras, digital video, and broadband digital data. Add a cable or digital subscriber line (DSL) modem on the front end of the hub, and the package is fairly complete. Generally the user interface would be a file browser like that of a PC desktop, modified for a TV screen, and a remote control.

On the output side, a digital hub would serve audio and video to every TV set, computer, and stereo in your home. This would require a wired—or preferably wireless—network, with cheap receivers scattered around the house to capture the digital signals and return them to analog form. (Wireless network receivers for PCs currently run under US $100 each, but hub makers would like to halve that figure.)

What does it take to perform all its functions? Inside, a hub may look much like an oddball PC from the last decade: a 32-bit CPU ticking over at a few hundred megahertz, with some multiple of 8MB of RAM, a video interface, and a digital signal-processing (DSP) chip or two to compress and decompress the video and transform the stored data into a format for display [see "Under the Hood,"]. It will also need 20GB of disk space and up, as good video requires about a gigabyte an hour, and audio needs about a megabyte a minute. (Once you have the CPU and DSP chips for encoding and decoding the streams of digital video compressed for broadcast or storage on a DVD, most of the other functions of a home entertainment gateway, including the user interface and music storage, are close to free.)

It will be the task of the designers to assemble a product that might have cost about $2000 five years ago but that today goes for between $250 and $500. That price would make it comparable to the cost of a typical new cable or satellite box.

Companies that currently have the most concrete plans for digital hubs range from electronics giants like Pioneer and Motorola to start-ups like Moxi Digital or established niche players like Metro Link and Cirrus Logic. (The latter two are offering "reference designs" for those who want to manufacture digital hubs using their chips and software.) Even IBM has a chipset it will be offering for a set-top box.

Moxi Digital (Palo Alto, Calif.) demonstrated what it called its media center hub at January's Consumer Electronics Show. It has a PVR, a CD/DVD player, innovative user-interface software, and a wireless home entertainment distribution network. In February, Digeo Inc. (Kirkland, Wash.), a start-up controlled by Microsoft cofounder Paul Allen, announced plans to build a strikingly similar hub in partnership with Motorola Inc. (Schaumburg, Ill.) and cable company Charter Communications Inc. (St. Louis, Mo.), also controlled by Allen. In March, Moxi and Digeo merged and took on the Digeo name.

The merged company intends to roll out Moxi's software on Motorola's set-top box hardware; it is also moving forward with tests of Moxi media center prototypes among subscribers to Echostar Communications Corp. (Littleton, Colo.), a satellite TV service. Established makers of set-top boxes, including Royal Philips Electronics (Amsterdam, the Netherlands) and Pioneer Corp. (Tokyo)—and, of course, Motorola—are building boxes that include high-speed data connections and home-network capabilities, in addition to the digital TV decoders of ordinary cable systems. Pioneer, for one, says its Digital Library unit will be able to store video, audio, and photos; download indexing information for music files automatically from the Internet; and serve multiple streams of audio and video throughout a user's home.

While the January Consumer Electronics Show saw companies in the PC business like Apple Computer Inc. (Cupertino, Calif.) and Microsoft gain the most press attention for their digital hubs, their plans appear to be the least well developed. Microsoft made headlines for a conceptual hub system built around a gateway computer and wireless Web-pad displays. Named Mira, the displays, which can show text or video and also act as remote controls, would be linked by the company's new Freestyle software modules to control plug-and-play entertainment units like DVDs, stereos, or home theatre installations, as well as home security system and lighting.

Microsoft's proprietary audio and video compression formats, along with digital rights management software to prevent unlicensed copying, would help create an apparently seamless package of Microsoft-controlled hardware and software. Microsoft's attempts to dominate the digital-entertainment arena have so far fallen short. Its proposed standard for an operating system for a next-generation set-top box was rejected in favor of a Java-based specification by both U.S. and European industry groups. And its Ultimate TV personal video recorder has made minimal inroads in the market (albeit total PVR unit sales worldwide reportedly still total less than three million, compared to more than 100 million VCRs in U.S. households alone).

Apple, for its part, has so far disavowed plans for a home entertainment gateway. Its "Rip, Mix, Burn" slogan for Macintoshes capable of writing CDs and DVDs, combined with audio, video, and photo editing software, appears aimed at people who create digital content, rather than those who simply enjoy it at home. Apple's iMovie lets people edit digital video and burn the resulting sequences on CD or DVD; iPhoto arranges digital photographs; and iTunes arranges music files for CDs or the company's iPod portable jukebox.

Yet another group of competitors is taking a software-only approach, relying on the computing power of present-day PCs. Companies like SnapStream Media Inc. (Houston) and Home Media Networks Ltd. (Edinburgh, Scotland) already sell programs, such as Home Media's ShowShifter, to turn a networked PC into a PVR and multimedia jukebox—essentially indistinguishable from a factory-built digital hub.

Concentrating on chips

Further down the manufacturing chain are the companies supplying chips. For example, in April, Conexant Systems Inc. (Newport Beach, Calif., formerly Rockwell Semiconductor Systems) announced a chip that combines digital TV reception with a cable modem. It lets cable operators sell broadband interactive services in a low-cost package that includes 100-plus TV channels.

In another effort, Cirrus Logic Inc. (Austin, Texas) has among its chips a combined DVD and digital-video chipset that powers Samsung's PVR. And on the computercentric side, there's Linksys Group Inc. (Irvine, Calif.). Best known for its pocket routers (units that connect small home or office networks to the Internet), it has a new chip that combines routing circuitry with a cable modem and a wireless network access point. Such a chip could be built into a stand-alone digital hub or slotted into a PC acting as a home server.

Software companies that produce middleware are offering development kits and pre-configured user interfaces for set-top hardware produced by a variety of manufacturers. Middleware is utility software that mediates between set-top applications, such as program guides or database browsers, and the underlying operating systems and hardware. Software from Mediabolic Inc. (San Francisco), for example, runs on IBM's set-top box chipset as well as on Pioneer's Digital Library.

As companies focus on putting together set-top boxes from chipsets, standards developed in the past year or two should make that job easier. Both the Multimedia Home Platform standard in Europe and the OpenCable Application Platform in the United States offer specs that enable any manufacturer to build hardware and compatible software, knowing that compliant programs will be able to run on them.

As a result, says Fran Helms, director of device and infrastructure partnerships for middleware maker Liberate Technologies (San Carlos, Calif.), manufacturers can farm out software development to different companies for different parts of their boxes—a user interface, for instance, or a new driver for printers attached through a USB port. What's more, with a broadband data connection, upgrading machines in the field becomes simple: the 50 kB or so of Java code required to implement a new user interface, for instance, could be downloaded to a digital hub in the time it takes to change channels.

Cutting costs by merging functions

Still, how do engineers cram what used to be thousands of dollars worth of video and computer equipment into an under-$500 box? By designing chips to do multiple duty, points out Anthony Simon, director of marketing for chip maker Conexant. For example, adding cable-modem functions to a video chip cuts between $20 and $40 from the cost of a set-top box.

And at PVR maker TiVo Inc. (Alviso, Calif.), product marketing director Ted Malone is proud of the subtle economies the company engineered into its custom disk-controller chip. The chip can read data streams from the disk surface in whatever order is most efficient for the head and then reassemble the information before handing it off to the video section.

Meanwhile, the price of hard-disk drives has put enormous volumes of storage within reach of even a run-of-the-mill set-top box. Currently, a 40-GB drive, which stores more than 50 hours of video, sells for about $80 retail and much less wholesale. Even a small fraction of that disk space can store dozens of hours of audio and thousands of digital photos.

Some of the money trimmed from hardware budgets is going to software R&D. When a hub has thousands of items available for its users to record, watch, or listen to, the conventional scrolling-list display of current set-top boxes is unusable, says Jakob Nielsen of the Nielsen Norman Group (Fremont, Calif.). Instead, a hub needs a search engine that, with only a few button-pushes, could find all movie musicals starring, for instance, Elvis Presley, or action dramas with Jackie Chan, or new episodes of your favorite home-improvement show.

The evolving interface

A first step up is an interface like TiVo's, where you peck out the name of the show on a virtual on-screen keyboard: as you type each letter, an adjacent display of potential matching titles gets shorter until only a few choices remain. Once the right show is found, recording its episodes is a matter of pressing just a button or two.

Moxi is simplifying matters further by mapping the letters most likely to be typed next to the numbers 1 through 9 on the remote's keypad. Typing text on a numeric keypad will be familiar to the millions of people who send text messages by cellular phone.

But this is just the beginning and there is a long way to go. As entertainment hubs start filling up with more than video, tools for browsing the material will become ever more important, notes Jakob Nielsen. Simple groupings according to title, artist, or kind of media won't be enough. Imagine trying to find movies with Elvis in a non-singing role scattered through a list of his more than 50 films, his hundreds of recorded songs, digitized photos, video clips, and a long list of Elvis impersonators, to say nothing of navigating around people with the same name, like figure-skater Elvis Stojko. Then imagine doing it with a dozen-odd buttons on a remote control; that is the goal.

Although software designers at digital hub companies speak confidently about handling multimedia complexity, Nielsen thinks such talk is bravado. It could be five years, or 20, or even longer before they develop interfaces with the intelligence to make mixed collections of audio, video, and digital photos (and accompanying text annotations) accessible without long manual searches. Eventually, Nielsen says, digital filing systems may recognize a face in an image or a voice on a soundtrack and read the identifying snippets of metadata that may accompany a file.

Whose box is it, anyway?

The battle for positioning among the would-be hub makers also has crucial implications for the financial, marketing, and legal battles that are likely in the nascent industry. Consider TiVo as a harbinger: consumers buy the current box for $400 (with prices coming down) but then they pay $12.95 a month for the program guide, without which the recorder is useless.

Moxi proposes an even more extreme version: cable and satellite companies would give its digital hub away for free and recoup the cost through monthly fees (much as they now do with set-top boxes). According to Toby Farrand, Moxi's chief technology officer, one hub plus one wireless extension would cost about $500, roughly the cost of the pair of digital cable or satellite boxes now installed gratis in a typical new subscriber's home.

Cable and satellite companies would profit from premium services—such as pay-per-view programs that benefit from a video recorder to store shows for later viewing, or from such services as Internet access or music downloading sold on top of the regular TV bundle. The merger of Moxi and Digeo will undoubtedly provide an excellent test bed for this business model since Paul Allen, who controls 75 percent of Digeo, is also chairman of Charter Communications. Charter, a cable company with seven million subscribers, has already installed Digeo software in half a million homes.

Cable and satellite companies who install digital hubs will also gain by having less customer turnover, asserts Orin Whatley, director of sales for middleware manufacturer Metro Link. Why would anyone switch from one cable company to another when returning their leased set-top box might mean losing not only their stored shows and recording preferences, but also the music, videos, and photo albums stored on the box's hard disk?

As cable TV companies, burglar-alarm suppliers, and even power companies negotiate for space inside digital hubs, Whatley foresees a sort of free-for-all to control a raft of functions also tied into the hub. An electric utility could, for example, manage loads more effectively, even turning off an air conditioner during peak periods. The system would also know when homeowners returned from work, so it could bring the house back to a comfortable temperature by the time they walked in the door.

With networked appliances, a digital hub would also offer new marketing opportunities, continues Whatley. For example, when your new stove registers its presence in your house with the hub and (through the Internet) with the manufacturer, it would be simple to send offers to your TV for an extended warranty or special accessories.

Will consumers be willing to rely on a single box owned by someone else for all their digital entertainment and home networking? Advocates of PC-based hubs, including Microsoft, are betting against it. Instead, software companies like SnapStream and Home Media Networks hope that customers will be willing to dedicate a cheap PC as their entertainment center. Millions of people already have those old oddball PCs in a closet or spare room that can digitize and play back video in real time. And new machines that can do this cost less than $500.

According to Colin Tinto, chief technical officer for Home Media's ShowShifter software, PCs with clocks of only 600 MHz can store raw video at a rate of about 4 GB/h and play it back in real time. (To save disk space, such a machine could compress video when nothing is being recorded, taking about three hours to process each hour of raw video.) Today's top-end machines could compress digital video as it comes in.

Media software from Microsoft, for example, can control the video hardware and encode and decode the video. Built-in file-sharing protocols make it easy to record and store video or sound on one computer and play it on another.

Law and the hub

Set-top hub proponents are confident, however, that a standard PC will never become a hub for the mainstream user. Why? Because if it's not illegal, they say it ought to be. The PC "is a hacker's paradise," contends Moxi's Farrand.

If so, hub makers are ready for them. For one, TiVo has designed its PVRs to encrypt stored video so that crackers cannot copy shows from one unit to another, or make Web archives for downloading by anyone. Samsung, for another, has inserted a block in its circuitry to prevent copying DVDs to the hard disk.

With an eye on Linux enthusiasts, the Recording Industry Association of America has already filed multiple lawsuits to prevent DVDs from being played on computers that run Linux, because Linux programmers haven't bought decryption licenses from DVD patent holders. And Microsoft's proposed antitrust settlement specifically protects the company's digital rights management software from disclosure.

In the U.S. Congress, the Consumer Broadband and Digital Television Promotion Act has been introduced. It would require all PCs and other devices that can store copyrighted material to contain hardware that would enforce copyright restrictions.

Clearly, with copy-protected compact disks already being sold, the Secure Digital Music Initiative for music available on-line, and encryption or watermarking proposed for pretty much every form of digital content, digital rights management will become an increasingly thorny issue for home-entertainment hubs. [See "Making Music Pay," IEEE Spectrum, October 2001, pp. 41-46, and "Getting Copyright Right," February 2002, pp. 47-51.] TiVo's Malone cites uncertainty in this area as yet another reason his company is moving slowly toward a multipurpose hub.

Dream versus reality

Any build-up to a single home gateway that controls your television, air conditioning, and e-mail will not come overnight, according to Jakob Nielsen. People won't replace their VCR, DVD player, and home network all at once, he points out.

Thus far, barring a few exceptions such as "universal" remote controls and serial control inputs for some cable boxes, manufacturers still seem focused on locking consumers into a single supplier. Whether that philosophy can stand up to the ultimate purpose of a digital hub—connecting all the disparate entertainment devices a consumer may own and even replacing some of them—is probably the crucial question for the evolution of this new technology.