OpenCable, the Cable Television Laboratories Inc.-managed
drive to foster interoperable digital set-tops, will issue drafts this week of the first
two documents comprising the OpenCable specification, just in time for the National Show.
The release of the specifications "marks a
milestone" in the OpenCable process, showing that consensus has been reached by
operators on most of the major features of the specification, said Bill Schleyer, a
CableLabs board member and chairman of its OpenCable Task Force.
The documents were posted on the CableLabs OpenCable Web
site (http://www.opencable.com), in a password-protected area viewable by CableLabs
members and by vendors involved in producing hardware or software for OpenCable.
Vendors ranging from Microsoft Corp. and Intel Corp. to
Sony Electronics Inc. and General Instrument Corp. are among the companies that have
participated in OpenCable to date.
The first document, "OpenCable Service
Requirements," defines features and services that operators want in OpenCable boxes,
said Laurie Schwartz, CableLabs' director of advanced-digital platforms and services.
The second document, "Set-Top-Terminal Functional
Requirements," is a more technical description of what the set-top must do to deliver
these services in a spec-compliant manner, Schwartz said.
Adjacent to the documents on the Web site is a form on
which vendors can submit comments to the team of 50 engineers from cable-operating
companies and CableLabs staff who are drafting the spec, Schwartz said. After three weeks
of vendor input, she added, "we'll review those comments with members and
incorporate them where appropriate."
The OpenCable team also planned to post for member review a
more detailed version of the specs "that drills down into the bits and bytes for each
interface," said Don Dulchinos, CableLabs' director of OpenCable.
After a member-comment period, plans call for CableLabs to
make the set of documents available to vendors by June 15, Dulchinos said.
The four detailed interface specs that the group considers
most important, Schwartz said, are those located between:
Set-tops and consumer-electronics devices, including
the existing, analog NTSC (National Television Systems Committee) TVs; HDTVs
(high-definition TVs); and audio equipment. As part of the spec, the group's choice
of high-speed interconnect standard IEEE 1394 to link set-tops to devices such as TVs and
DVD (digital versatile disc) players was announced in March.
Set-tops and a "point-of-deployment security
module." That module comprises a PCMCIA card that slips into a slot in the set-top.
Set-tops and the cable network.
The cable headend and external networks, with
special attention to connectivity with digital-broadcast signals and with Internet-content
The security module, which cable operators will provide to
their subscribers, will be important for selling the boxes to consumers in retail outlets,
"When a customer buys a digital box in Denver, he gets
a security card from the local operator. When he moves to California, he takes the box
with him and gets a new card from his new MSO," Dulchinos said.
A "software-application-environment document" is
scheduled to be sent to CableLabs members for comment by mid-May, then to vendors during
June, Schwartz said. It defines the interfaces -- or application-program interfaces --
between the set-top's operating software and the various applications being used by
content providers, Schwartz said.
Add up all of the pieces, Schwartz said, and the spec
"should be pretty much complete by fall."
Schleyer said the team plans to set up an interoperability
and branding process similar to the DOCSIS (Data Over Cable Service/Interoperability
Specification) process for cable-modem certification.
After lab testing, which CableLabs hopes to begin in the
first half of 1999, products certified as spec-compliant can bear a label attesting to the
fact. This branding, Schleyer said, "is a promise to consumers that the box will work
on any OpenCable-compliant cable system anywhere."
The first wave of boxes -- which will be purchased by MSOs,
rather than consumers -- will be "OpenCable-compatible," rather than
"OpenCable-compliant," since their security control will be "embedded"
inside, rather than on a removable card, Schwartz said.
This is another in a series of articles submitted by Cable
Television Laboratories Inc. about trends in cable.