Prodded by Kennard, CEMA, Cable Near Fire-Wire Spec

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Two industry groups are racing to meet regulatory approval
in order to solve the complicated "fire-wire" problem of sending high-definition
television signals through set-tops to HDTV sets.

Cable Television
Laboratories Inc.
-- which recently dubbed its fire-wire work "HDNI," for
"Home Digital Network Interface" -- is expected to release a second draft
specification Sept. 4 that will go out for vendor review shortly after that.

And the Consumer
Electronics Manufacturers Association
, at a meeting two weeks ago in Chicago, finally
reached accord between two separate and competing fire-wire subcommittees -- one anchored
by Sony Corp. and the other by Thomson Consumer Electronics.

Jeffrey Krauss, president of consultant firm
Telecommunications and Technology Policy, attended the recent round of meetings in
Chicago, and he said both vendors were holding out to use their own fire-wire protocols,
but Thomson finally ceded.

The CEMA subcommittees, "R4.1" and
"R4.7," were combined and renamed "R4.8," Krauss said, adding,
"They've now agreed to come up with a final draft by Sept. 10 and final adoption
as a standard by Oct. 15, which would be a real record."

Those two groups were working separately on the development
of fire-wire protocols, or the "language" that runs over the wire.

The sudden race to agree and cooperate on fire wire stems
in part from a sharply worded letter written by Federal Communications Commission chairman
William Kennard to top officials at the CEMA and the National
Cable Television Association
.

"The FCC finally understood that it was this fire-wire
fight that was holding things up," Krauss said.

Fire wire, also known as the IEEE 1394 standard, is
especially critical to HDTV deployment because of the amount of data crammed into an HDTV
signal: Without fire wire, it would be expensive, and perhaps impossible, to send the
1.2-gigabit-per-second (uncompressed) HDTV signals through cable set-tops to TV sets.

Cable officials said fire wire is just one portion of its
HDNI (pronounced like the magician) work.

"HDNI spawned from the increased importance given to
HDTV transmissions by the FCC," said Don Dolchinos, director of business development
for CableLabs. "Fire wire is one part of HDNI -- HDNI is the whole interface between
the set-top and the receiver, and anything else that we need to connect to."

The cable-oriented HDNI solution is different from existing
fire wire because of an ironic reality: Fire wire actually isn't fast enough to
support the huge amounts of data that make the pristine HDTV pictures.

Uncompressed HDTV signals run at 1.2 gbps, while fire wire
currently tops out at 400 kilobits per second, MSO executives said.

That's why the latest round of work requires a great
deal of cooperation between cable and consumer-electronics companies to split up some of
the HDTV decoding and processing tasks between the set-top and the HDTV receiver, which,
in turn, lightens the load on the fire wire.

"If you can move parts of [HDTV processing] to the
set-top and parts to the TV display, you don't have to worry about the fact that you
can't get 1.2 gbps over the fire wire," noted Mike Hayashi, vice president of
advanced services for Time Warner Cable.

Hayashi and others said technical snafus remain with the
HDNI approach, including how to send navigational-guide data.

Another issue, he said, is whether consumer-electronics
manufacturers will like the idea enough -- and view it as enough of a margin-builder -- to
adopt the approach.

"It remains to be seen" whether manufacturers
like the HDNI approach, Hayashi said. "So far, though, it looks pretty good."

Historical efforts between the cable and
consumer-electronics industries haven't exactly been shining examples of
cross-industry harmony.

Earlier attempts, as long as 15 years ago, to develop a
"multiport" connector for handshaking between analog set-tops and
consumer-electronics devices ended up in a hopeless chicken-and-egg situation, where TV
manufacturers wouldn't install the plugs until set-top manufacturers did, and vice
versa.

But MSO and CableLabs executives cited many rounds of
recent meetings, coupled with a true need for cooperation, as drivers toward a workable
solution.

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