Sony Passes Comcast Test


Comcast Corp. gave Sony Corp.'s Passage technology a key stamp of approval last week, disclosing that it successfully completed a trial that's supposed to let cable operators use various set-tops in legacy cable systems and speed the transition to all-digital operations.

"The Sony technology is terrific for transition scenarios like the transition to an all digital-world and from one conditional-access [technology] to another," Comcast chief technology officer David Fellows said in an interview last week. "As we plan our all-digital transitions, this is a terrific tool that gives us flexibility in planning that transition."

Fellows stopped short of saying that Comcast was ready to order the technology for mass rollout. "We just want to convey the testing went very well," he said. "The trial was a success and this is a technology we can utilize as we figure the steps [in the digital transition].

"We proved that [in] whatever legacy systems exist, this can be rolled out."

Sony introduced the Passage concept at the Western Show in late 2002. "The core of Sony Passage is to enable multiple conditional-access systems," said Sony Electronics senior vice president Greg Gudorf.

Passage allows MSOs to create a second set of encryption keys within each programming stream.

In a typical cable system, Motorola Inc. or Scientific-Atlanta Inc. embeds encryption keys within the transport stream of each program channel.

When a subscriber tunes to a channel, the corresponding Motorola or S-A set-top in the home looks for those keys to that channel, whether it's Home Box Office or MTV: Music Television.

Both S-A and Motorola employ proprietary encryption systems, although each has sublicensed parts of the technology so that boxes from Pioneer Electronics Corp. or Pace Micro Technologies, for example, can work with either headend.

Sony's Passage technology introduces a duplicate encryption key embedded alongside the Motorola or S-A key in each signal, bypassing current legacy systems without interfering with them.

In the Comcast trial, carried out in an undisclosed market, a Sony set-top box was used with conditional-access technology from NDS Group plc.

The test used Harmonic Inc. video processors that were Passage-enabled, as well as stream multiplexing. The second set-top was from Motorola, vendor sources said.

ETI Software handled the billing and subscriber-management systems. Fellows said that's important, because the billing system is the repository of the conditional-access information, or the data on which homes subscribe to particular channels.


The trial, announced last summer at the National Show, was completed a few weeks ago. "The goal was to allow all forms of the set-top network and the [set-top] network headend equipment to all work together," Fellows said.

There is no Sony hardware in Passage, Gudorf said. Rather, Sony software is embedded within the Harmonic video processor.

Passage looks at the incoming digital stream, identifies the critical packets to encrypt, then duplicates those packets in a separate encryption system for transmission.

Operators can decide how much of the signal they want to encrypt, Gudorf said.

Fellows called Passage one piece of the puzzle that relates to the transition to an all-digital network, as well as the introduction of multiple conditional-access systems inside existing systems.

As a first step toward an all-digital network, Comcast could create new digital multiplexes in 6-Meghahertz packages and use Passage to deploy them, alongside existing channel lineups.

The evolution of Passage goes hand in hand with the development of a low cost set-top in the $35 to $50 range, part of the appeal of an all-digital network.

Fellows — who has advocated a speedy transition to all-digital systems — said he's evaluating proposals from traditional set-top vendors and cable-modem suppliers.

"We're right at the phase where everybody has a good idea," he said. "Everybody wants a piece of this market.

"If for $50, I could get a digital set-top box, a conditional access system, a separate [Data Over Cable Service Interface Specification] gateway channel with a link signal into that box and an advanced video codec," he said, Comcast would be interested.


Charter has taken its first step toward an all-digital network, launching an all-digital system in Long Beach, Calif., alongside the legacy analog-and-digital network.

"All the operators are all doing similar planning, and the same analysis," Fellows said. "We'd love to see a common vision on architecture and standards. Passage is one of those technologies that gives you confidence to plunge into this all-digital world."

"The technology is the right thing to do moving forward," said Yaron Simler, president of Harmonic's convergent systems division, because it allows cable operators to put other set-tops in homes. "It creates competition to keep people honest, and that's a good thing," he said.

"The trial was very, very successful," said NDS America vice president and general manager Dov Rubin. NDS technologies are embedded within Cablevision Systems Corp.'s Sony boxes.

"It gives the ability for the cable industry to open the door to get open technology, second source providers and keep costs down for consumers," he said.

That open door also is part of Sony's end game to sell more set-tops. "We hope to enable a market for consumer electronics that works on cable systems," Gudorf said. "The most important thing about Passage is to open the market that's been closed to us."