Progress Reported on IEEE 1394

t appears likely that a copy protection solution for an interface between digital cable set tops and digital televisions will be finalized by early November.

The cable and consumer electronics industries have been working on the interface for some time. In August, FCC Chairman, William E. Kennard, contacted top consumer electronics and cable officials urging them to resolve their connectivity problems by November 1, and indicated that the government may step in if they failed to do so.

In March, CableLabs® announced its choice of an interface format, IEEE 1394 (also known as FireWire), as the link between digital set tops, digital TVs, and other devices that would be incorporated into the OpenCable specification. "The interface, however, needed copy protection to meet the needs of the movie studios," noted Laurie Schwartz, CableLabs' vice president of advanced platforms and services.

A breakthrough on the copy protection issue occurred in mid-summer when an ad hoc inter-industry group, the copy protection technology working group (CPTWG), considered three copy protection solutions. These included what is known as the 5C digital transmission content protection (DTCP) specification (named for the five-company compromise among Sony, Mitsubishi, Intel, Toshiba, and Hitachi). "To be truly interoperable, set tops need to have just one approach for copy protection," Schwartz said. She added that 5C seems to be the leading candidate.

Accordingly, CableLabs proceeded to incorporate the 5C approach into the home digital network interface (HDNI) section of the draft OpenCable specification.

In September, the consumer electronics manufacturers association (CEMA), a unit of the electronic industries alliance (EIA), announced that it was working on a standard that would employ IEEE 1394 as one of four methods linking future digital TVs with other devices, including cable set tops. CEMA formed an R4.8 1394 interface subcommittee to write a proposed EIA standard. According to George Hanover, vice president of engineering at CEMA, as of mid-October, a working group was collecting information from proponents of several copy protection solutions, including 5C, and was due to present an evaluation to the R4.8 subcommittee.

Possible options include supporting multiple copy-protection approaches, letting the marketplace decide, or adopting just one approach. Hanover added that "5C is certainly a strong contender and we're looking very closely at it."

The R4.8 subcommittee is expected to vote on the proposed EIA 775 DTV 1394 interface standard at a meeting scheduled for November 11. "The standard," Hanover said, "has a lot of commonality with what the OpenCable group has done," in part because of an on-going dialog between the two groups.

To manage a variety of compatibility issues between devices, the CEMA and OpenCable groups also are working to develop "command and control" signaling. In addition, the industry still has concerns about the price tag for HDNI (among the costs are royalties for 1394 and for 5C).

"Another looming task," said Schwartz, "is completing a specification for a removable security card in time for a planned late-November unveiling. After that comes the crunch to get OpenCable boxes built and on the market-ideally by the end of 1999."