OpenCable on Track; Two Draft Specifications Issued to Suppliers

ignificant portions of the draft OpenCable specifications are largely complete, and the first draft documents are being released to the vendor community for their review and comment.

"This puts OpenCable right on track to meet the cable industry's needs for interoperable digital set-top devices," said William T. Schleyer, chairman of the OpenCable working teams that are developing the specifications.

The OpenCable digital platform is a CableLabs-managed initiative aimed at developing key interface specifications to foster interoperability among advanced digital set-top boxes built by multiple vendors and used in broadband two-way cable networks. OpenCable is consistent with, and furthers the goals of, Section 629 of the Telecommunications Act of 1996 that requires competitive availability of navigation devices.

The first two documents released are a service requirements document and a functional requirements document. The service requirements document is a brief description of what services an OpenCable set-top box must be capable of supporting. The functional requirements document is a more detailed discussion of what technical capabilities will be required in the box.

"These are the first in a series of documents that are in the pipeline," said Laurie Schwartz, CableLabs director, Advanced Platforms & Services. More detailed interface specifications, which will provide enough information to enable suppliers to actually build an OpenCable box, are now under review by the cable operator representatives on the OpenCable team, and will be released to the vendor community for review and comment in mid-June, she added.

"The release of these documents keeps us on track for completing the specification in 1998, the original goal of the project," according to Don Dulchinos, CableLabs director, business development. "We're beginning to design a process to certify boxes as cable operators begin to take shipment on their recent orders," he added.

In addition to the drafting of the documents described above, work continues to progress on reaching industry consensus on a number of issues raised by the OpenCable effort.

Critical Harmony technology, such as the agreed upon modulation and MPEG formats, has been tested. The Harmony core decryptor has been designed and initial testing has been performed. GI and SA are in the process of implementing an architecture that will allow an operator to use DigiCipher II and PowerKEY in the same system.

The software technical team has made significant progress in defining the software architecture and OpenCable application programming interfaces (APIs). The members have agreed on the architecture and process for defining the remaining open APIs, standardizing on an open middleware architecture that leverages existing Internet technology.

OpenCable set-top boxes are based on high-performance microprocessors with real-time operating systems. The Open-Cable initiative does not specify a single microprocessor or operating system. Most interactive services will be implemented at the middleware layer using existing open Internet specifications, including HTML, CGI, JavaScript, and popular plug-ins.

The OpenCable project continues to have the strong support of Silicon Valley; companies like Microsoft, Network Computers Inc., Oracle, Sun Microsystems, and others continue to provide information to the OpenCable team. Companies from the computer industry also are busy forming business arrangements with individual cable companies to contribute their technologies to cable operators' set-top orders.

"General Instrument has committed a large amount of resources to this activity and we continue to be highly motivated by the activities in OpenCable and the aggressive pursuit of specifications and, ultimately, a new generation of products," said General Instrument President and CEO Ed Breen.

"The OpenCable initiative has made significant progress over the past year," said Larry Ellison, Chairman and CEO of Oracle Corp. "Through Oracle and our Network Computer, Inc. affiliate, we have always advocated standards-based cable technology which will speed the deployment of Internet-based services into the home."

"We're honored to be serving a lead role in developing OpenCable's system integration and set-top specifications," said James F. MacDonald, Scientific-Atlanta President and CEO. "The project's outcome will be a tremendous boon for the cable industry, so we're delighted that the OpenCable team's efforts are quickly coming to fruition."

The project also relies upon many components that already have been standardized. For instance, in March, OpenCable announced it had specified an existing high-speed interconnect called IEEE 1394 as the link between OpenCable advanced digital set-top boxes and devices such as television sets and digital videodisk players. This 1394 interface allows for pass-through of vast amounts of data at rates up to 400 million bits per second, which is important when delivering digital video and data services.

A high definition reference architecture has been agreed upon that will enable OpenCable set-tops to deliver whatever HD formats broadcasters decide to transmit. The OpenCable team is working on several technical solutions that will allow the members to meet this objective in the immediate future and in the long-term.

The OpenCable effort has been working closely with another CableLabs-managed interoperability project known as DOCSIS (Data Over Cable Service Interface Specification), which is nearing an interoperable cable modem architecture. DOCSIS modems will be made part of some elements of the OpenCable family of digital devices.

OpenCable FAQ

Q. What is OpenCable?

A. OpenCable is a cable television industry fast-track initiative being managed through CableLabs with a goal of attaining interoperable digital set-top boxes manufactured by multiple vendors. These devices would be capable of delivering digital video, data and interactive services to a television set. The OpenCable initiative has a number of components: (1) It is the process that will define the advanced digital devices, including set tops. (2) It is a blueprint for a way of delivering a series of advanced services to consumers. (3) It is a family of cable digital devices. (4) It is a consumer brand.

The process of OpenCable entails a team of CableLabs technical staff working with technical representatives from member companies. There is a parallel team of cable company business executives also involved in the OpenCable process. The CableLabs Executive Committee initiated OpenCable in spring 1997 with a series of meetings with top executives at computer industry companies. There followed another series of meetings of CableLabs, cable chief technology officers, and computer companies. OpenCable was launched in July 1997 and a request for information was issued to leading consumer electronics and computer industry companies.

Twenty-three companies responded and their data were reviewed by technical teams from CableLabs and member companies and by business teams from cable system operating companies. The commonality of these responses led to the CableLabs Executive Committee reaching consensus on some key elements in November 1997 and agreeing to put the project on a fast track. Since that time, the working groups have been busy writing a specification for the core functionality of OpenCable devices.

The process is intended to foster competition among suppliers for key elements of digital cable networks, while ensuring interoperability of devices connected to cable networks. The Executive Committee chose to pursue an open specification rather than to anoint a single proprietary solution. This competitive environment will, in turn, lead to competitive pricing for set-top boxes and, the introduction of digital cable-ready television sets and set tops into retail distribution. OpenCable also will provide cable with a highly flexible platform for the introduction of new services and revenue streams.

The OpenCable architecture component could be thought of as a blueprint for suppliers to use in building advanced digital set-top boxes. It will provide suppliers with plans of how to build advanced set-top boxes and will allow those suppliers to migrate OpenCable functionality into a family of other devices, including VCRs, television sets, DVD players, and personal computer cards.

Q. What were those key elements that the Executive Committee agreed upon?

A. The key OpenCable interfaces that were agreed upon include the formats for digital cable television signals (MPEG-2), the consumer privacy system, and the interfaces for high-speed connections to the Internet (Data-Over-Cable Service Interface Specification [DOCSIS]). The OpenCable teams are continuing to work on the interfaces required to author interactive applications and the copyright protection system.

It also was agreed that OpenCable set-top boxes will be based on high-performance microprocessors with real-time operating systems. The Executive Committee agreed not to specify a single microprocessor or operating system. Most interactive services will be implemented at the middleware layer using existing open Internet specifications, including HTML, CGI, JavaScript, and popular plug-ins.

Q. What is the current status of OpenCable?

A. Technical teams at CableLabs and its member companies, working under the direction of William T. Schleyer, are nearing completion of a draft specification for OpenCable and will soon distribute it to suppliers. Suppliers will have a chance to make comments and the specification will be edited, if necessary. The specification will be considered complete at that point. CableLabs has contracted with Scientific-Atlanta to assist in integrating the various components of the specification. Their expertise in this area will help to ensure that the different specifications ultimately do work together in an end-to-end system.

Q. If the specification is not complete, how could CableLabs member companies be announcing purchase orders as early as January of this year?

A. CableLabs members have stated in their purchase orders that whatever they buy under those agreements must first comply with the OpenCable specification. CableLabs is establishing a certification process that will be put into place to give suppliers an opportunity to have their products tested and then credited with compliance by a certification board. That process will be created later this year and will be ready to certify boxes shipping at that time.

The announced purchases include 15 million units ordered from General Instrument by a consortium of cable operators that includes TCI, Time Warner Cable, MediaOne, Cox Communications, and Comcast Corp. Another group of cable operators has ordered 1.4 million set tops from Scientific-Atlanta. These operators include Time Warner Cable, Comcast, Adelphia Communications, Cox Communications, Marcus Cable, MediaOne, Rogers Cablesystems Ltd., Videotron ltee, and Cogeco Cable.

Q. How does OpenCable account for high definition television (HDTV)?

A. HDTV is foreseen as a key component of cable television's programming service for the future. The cable industry is format agnostic on HDTV. So, the OpenCable boxes will pass through any of the formats approved for advanced television by the Advanced Television Systems Committee. The industry intends to pass signals to a HDTV set without impairing either the audio or video quality. The cable industry, through CableLabs, has been involved in the HDTV process since its inception through work at the Advanced Television Test Center (ATTC) and through CableLabs request for information and request for proposal that date back to 1991. CableLabs also has conducted HDTV field tests with the ATTC via cable operating systems located in Charlotte.

HDTV requires a higher bit rate and greater bandwidth than current NTSC television. This will be accommodated by way of a special interface that will connect the OpenCable set-top box with digital television. This interface, called the IEEE 1394, is named after the Institute of Electrical and Electronics Engineers (IEEE) that standardized it. This interface may accommodate 400 million bits per second of throughput, and there are efforts underway to expand that capacity to one billion bits per second. Because IEEE is standardized, it exists, and is capable of carrying the payload cable operators will deliver, it fits nicely into the OpenCable family of specifications.

Q. It seems that there is a lot to do in a short time with regard to OpenCable. How can it possibly get product into the marketplace this year?

A. Cable operators will continue to deploy advanced digital set tops this year, such as the Explorer 2000 and the DCT 1200 boxes. These devices are consistent wholly with the OpenCable architecture. OpenCable products that are portable and that are available in the retail marketplace are not anticipated in large volumes until the middle of 1999. The process is capable of moving that fast because OpenCable relies upon a great many protocols that have been standardized by organizations such as the IEEE, the Internet Engineering Task Force, and the International Telecommunications Union (ITU).

Q. What about the Internet connection in OpenCable?

A. All set-top devices in the OpenCable family of products, which also will include VCRs, television sets, and DVD players, will have the ability to offer an enhanced television viewing experience by way of some data complement to the video. In the devices that cable operators lease to customers, there may be a "small footprint" software in the set top that communicates with a server in the cable operator headend. In the higher-end devices that customers may buy at retail, the box may contain a fully functioning DOCSIS modem that allows high-speed two-way Internet access via the cable plant. OpenCable accommodates either strategy. It also accommodates different extensions of OpenCable functionality that some cable operators may wish to obtain to meet their market needs.

Q. OpenCable has been described as several things, including a brand. What does that brand mean?

A. The word OpenCable may appear on set tops, personal computers, television sets and more. It is a commitment from the cable industry to make cable set-top boxes available at retail. Our pledge as an industry is that OpenCable boxes have been certified by CableLabs as being interoperable, with a whole family of devices, on every participating cable system. The Open-Cable brand devices will be portable. That is, they may be purchased in one community and will work in any other community where the cable operator supports OpenCable.

Q. A lot of what OpenCable is about has to do with computer software and operating systems. Where is the cable industry getting the expertise it needs to monitor these software developments?

A. The cable industry wishes to attract new suppliers. These suppliers will bring new concepts and capabilities along with technologies that will complement the efforts of the industry's traditional suppliers. Much of the expertise that is part of OpenCable is coming from the suppliers that wish to participate in the OpenCable process. Because the CableLabs Executive Committee chose to have OpenCable remain nonexclusive with regard to computer operating systems and to microprocessors, a number of computer software companies may participate in this process. These include companies with operating systems like Microsoft, Sun Microsystems, and PowerTV. While having these companies involved and working together with the cable industry is appreciated, the industry also is intent upon not giving up control of this effort. A second layer of computer software issues may arise around the application programming interfaces (APIs). The cable industry wishes to be inclusive on APIs because it is at this level that many services will be enabled. That expertise is available and is being added to the cable industry rapidly.

Q. How far along is the Harmony agreement on transport and encryption between traditional cable suppliers General Instrument and Scientific-Atlanta? Can other companies license this technology yet?

A. OpenCable is continuing to work with GI and SA to ensure that conditional access is not a roadblock to OpenCable deployment. CableLabs announced in October 1996 that the two companies had agreed. One year later they had worked out an agreement, and we are confident that more progress will occur. In 1996, we announced that CableLabs and its members had agreed upon major elements of a specification that covers how cable systems will transport digital video and data. Among the areas covered in the specification are that systems will conform to MPEG-2 main profile at main level parameters, that the specification transport multiplex will also be MPEG-2, and that the audio element will be Dolby AC-3. As for signal security, the General Instrument DigiCipher implementation of the DES encryption standard was set as the core encryption system. Multiple conditional access and control data streams, such as PowerKEY and DigiCipher, will be supported. Downstream digital modulation will conform to the ITU standard ITU-T J. 83 Annex B. This standard calls for 64 and 256 quadrature amplitude modulation (QAM) with concatenated trellis coded modulation, plus enhancements such as variable interleaving depth for low latency in delay sensitive applications such as data and voice. Using 64 QAM, a cable channel that today carries one analog video channel could carry 27 Mbps of information, or enough for multiple video programs. Using 256 QAM, the standard 6-MHz cable channel would carry 40 Mbps.