By: Sun_Zoom_Spark $$$$
Reply To: None Friday, 7 Jul 2000 at 5:27 PM EDT
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NO LINK: The other article
This article is from the July 2000 print edition of Communications Technology Magazine, the official trade journal of the Society of Cable Telecommunications Engineers.
INTERACTIVE TV PLATFORMS
Now The Quarterback Really Can Hear You
BY Arthur Cole
So the network's been upgraded to two-way, 750 MHz or better, the head-ends, nodes and hubs are outfitted with the latest transmission gizmos, and the boss is ready to start counting all the new money. There's only one small step remaining on the road to interactivity: selecting the platform.
As you can probably guess, there are scads of systems out there, each with its own feature sets and hardware and software requirements. But probably the most important thing to know about the different platforms is that each has a unique design philosophy that will largely dictate how your system will grow and evolve in the future. That's right-before you buy now; you'd better know what you're going to need in the future.
''Make sure you have a roadway that takes you into the latter part of this century'' says Beth Loughney director of product marketing at OpenTV.
From the consumer point of viewy all of the leading platforms will provide essentially the same services: a-mail, Web browsing, interactive programming, online gaming and so forth. lf any of these applications are not part of the basic platform, it most likely will accept thirdparty applications. All of the major systems also will communicate with the new lines of set-top boxes, provided they are spendable compliant. If anyone tries to tell you that OpenCable is not necessary think twice about buying their system. All of the
major set-top manufacturers - particularly Motorola and Scientific-Atlanta - are backing OpenCable. When set-tops hit the retail market, it will greatly enhance your ability to attract new digital customers if they know they can use any box off the shelf, it's also important to note that selection of one platform does not mean you are excluded from using all or part of another. OpenTV for example, can run ACTV and ICTV as a secondary feature set, even though the latter systems also can be used as a base level platform.
Although the systems are continually evolving, it seems that the three main base level platforms are OpenTV, Liberate and Microsoft TV. ACTV, ICTV, Wink, WorldGate and a host of others are seen largely as upper level software packages that may or may not be
suitable as a basic platform. Every day new interactive players emerge, so be warned, this is not a complete rundown of every vendor out there.
Here then is a rundown of some of the major systems.
ACTV
ACTV is available in three iterations. The basic level system that allows viewers to participate and interact with a TV show requires only a digital set-top in the home. Like any other digital service. the headend needs to be able to pass through the service using either a satellite receiver or via fiber. The viewer essentially interacts with the programming using the memory and intelligence of the set-top.
The next step up is addressable advertising. This uses essentially the same technology as mentioned earlier, except that now the headend is outfitted with a transport remux unit. This allows operators to insert local ads into the digital stream.
In some cases. response information may be sent to a centralized database somewhere, in which case a data circuit would need to be established between the headend and the data warehouse. This can be accomplished with a simple outbound lnternet connection.
The most advanced level is called HyperTV designed to bring about TV/Web convergence programming. Using either a Web-capable set-top or a TV set and personal computer (PC) side-by-side, the cable operator sends specialized programming through the cable plant using WorldGate, ICTV or another platform. Responses are routed back to the headend and beyond using existing return path equipment.
''We're not talking about just surfing the Web. We are creating content,'' says Kevin Liga, chief technology officer at ACTV ''We are a content player out there.''
ICTV
ICTV has adopted a duel-client architecture that places all of the brains of the system in the headend with only basic level set-tops in the home. The company says this provides two advantages to cable operators looking to roll out digital services. First. it allows customers to get online with extremely cheap hardware, and secondly it allows new services and greater processing power to be added without requiring customers to invest in new boxes on a regular basis.
Was Hoffman, president of IC-IX says this is the most efficient solution because all of the processing is centralized at the headend, rather than split between the set-top and headend.
''lf you split the processing, you lose some of the interface characteristics with the application.'' he says. 'For Web browsing, if anything happens in the (headend-based) browser environment, the worst thing that happens is the customer is turned away. If the application is running from the set-top, you now have to reboot the box.'' ICTV uses the lSX-2000 headend system, a rack-sized unit that contains up to 45 PC modules inning Windows applications, such as Internet Explorer, located in the system's content server. The package also uses an NT sewer for data management and storage. Hoffman says that a pair of ISX-2000s requiring only two racks of space in the headend will serve upwards of 50,000 customers.
Liberate
The Liberate platform is extremely flexible in that it will work across all manner of infrastructure and set-tops. This lets the operator decide how much intelligence to locate in the home or in the headend. The system runs on off-the-shelf Sun or Windows NT sewers and utilizes most of the common Web standard: hypertext transfer protocol (HTTP), hypertext markup language (HTML), JavaScript and so on. One of the unique advantages to Liberate is that it allows users to mix and match different set-tops in the home: an advanced DCT-5000 in the living room, with the simpler DCT-1000 upstairs, for example.
Company executives say this flexibility will help operators better manage their systems in the long run. ''The server-side solution has a problem as more customers use the service,'' says Steve Weinstein, chief technology officer at Liberate. ''lf you want to maintain that rich experience, increasing take rates become a bad thing.''
Liberate also is unique in that it provides a broadcast, rather than point-to-point, service when it comes to interactivity.
"We're not trying to duplicate the Web '' Weinstein says. "A broadcast model saves bandwidth going to the box and to the servers, and there's no impact on the system if 10,000 people all want to view CNN.''
Microsoft
This one is largely an enigma because few people have actually seen it. (Can anyone say vaporware?) The company is looking to leverage the WebTV product, which uses phone lines for the return path. into an interactive cable system. But so far, all we are told is that it will consist of a client-software package for TV and set-top systems and a server system for the headend.
The server is to be based on the Windows 2000 operating system, along with Microsoft SQL Server 7.0 and Web-TV software. The system will support Advanced Television Enhancement Forum (ATVEF) specs, along with the usual HTML, HTTP, Javascript
and Data Over Cable Service Interface Specification (DOCSIS) standards.
Microsoft officials were unavailable to comment on the system.
OpenTV
With a host of installations throughout Europe, Asia and Africa, OpenTV has a lot of experience in real-world cable TV applications. However, the company has yet to announce a U.S. rollout and is essentially starting from scratch in this market.
Hardware-wise, the basic OpenTV package requires installation of the OpenTV Frame Moving Picture Experts Group (MPEG) encoder that converts different file formats such as tag image file format (TIFF), graphics interchange format (GIF), Joint Photographic Experts Group (JPEG) and such into MPEG stills for display on a TV screen. But for a true interactive experience, most operators will want to install the OpenStreamer system that allows interactive content to be delivered using standard digital cable equipment. With this software, data that is multiplexed with audio and video can be updated in real time for instant transmission of sports scores, stock quotes and so forth.
OpenTV works with off-the-shelf hardware and fits into existing infrastructures and system architectures. ''Most operators have already made the decision on what they want their infrastructure to look like'' Loughney says. ''We don't want to make that decision for them. We've already integrated with operators all over the world, and we've seen some pretty strange configurations.''
OpenTV also provides an authoring tool set for content providers to develop all manner of interactive applications.
Wink
The one unique aspect about Wink is that it really isn't unique. It incorporates features and systems found in nearly all of the other interactive systems. Wink authoring tools are used to create enhanced programming, and the Wink Broadcast Server inserts this data or uniform resource locator (URL) links into the video stream. All that is required at the headend is a server, if the operator is interested in providing local content, and an interface to a centrally located Wink Response Server to reply to interactive commands.
Wink is mostly interested in providing interactive network services, so the company isn't really picky about which client software or protocols are used. ''In the long run, we don't care whether operators deploy an ATVEF client or a Wink client or some other, as long as we can provide our network services,'' says Allen Thygesen, executive vice president of sales and systems development at Wink. "We don't really want to be in the business of fighting over which protocol anyone should be using.''
WorldGate
WorldGate also has a system that centralizes the intelligence at the headend under what it calls an ''Ultra-Thin Client'' architecture. As noted earlier, this reduces the cost of set-top hardware and makes it easier to add new services.
WorldGate's Channel HyperLinking technology offers real-time connectivity to Web sites related to the programming being viewed. Not only does this offer possibilities for additional ad revenues, cable operators may even charge portal and transaction fees and receive additional revenue for banner ads, search engine capability and chat services.
Like the other centralized services, more users will eventually lead to more hardware at the headend as more CPU cards are added. However, when compared to what will be required for video-on-demand (VOD) operations, WorldGate will take up very little space in the headend.
"There's no integration (of systems) required from the cable operator,'' says Ed Lee, vice president of operations at WorldGate. ''Backend support is supplied by us. lf a cable system runs into any trouble, they can place a call and get a quick resolution.''
Wrap up
Clearly there's more to these systems than can be explained in a single magazine article, and every cable system will have unique features that engineers will want to keep in mind when evaluating the various platforms. But because most of these systems are based on off-the-shelf hardware and are compatible with spendable and other networking protocols. there probably isn't a system in operation today that couldn't run any one of these packages without a little software tweak here and there. |
