Cable operators opt for data modems

Cable operators opt for data modems

Dave Powell

A technology fight is brewing between cable-TV providers and telephone companies. At stake is which communications organization will be the first and fastest to bring multimedia video, data and Internet-access services into America`s homes.

The combatants` battle strategies are fundamentally different, based on their distinctive network-cable infrastructures. In one corner, cable-TV providers hope to bring broadband video/data into America`s homes over their services` existing fiber-optic/coaxial-cable lines. However, telephone companies contend that their larger fiber/copper networks can bring data into more homes faster.

The winner, however, may be determined more by fancy marketing footwork than by the advantages of either fiber or copper-cable technology, in the opinion of industry analysts and players.

To illustrate, at the Western Cable Show held in Anaheim, CA, last December, cable-TV service providers agreed on a way to develop standards for high-speed communications over cable networks and to sell compliant cable modems by the fall of 1996. These modems would support 27 to 40 megabits per second of data and video images into the home and 1.5 to 6 Mbits/sec of data from the home back into the network. Standardization lets different vendors sell modems for use in any cable system and permits these devices to be sold through consumer-electronics channels.

Brian Roberts, president of Comcast Corp., a system developer, says that compared with telephone companies` network capabilities, these speedy modems will be "like airplanes versus cars." His observation voices a common industry viewpoint that the telephone companies` copper-to-the-home cannot match cable-TV providers` coaxial-cable speeds.

John Malone, chief executive at Tele-Communications Inc., agrees. "The telephone industry is not capable of providing anything like this," he says. Backing this campaign are several coalitions of multimedia service providers and cable-equipment manufacturers. Pushing the standards-development process are Cable Television Laboratories Inc., Comcast Corp., Continental Cablevision Inc., Shaw Communications Inc., Silicon Graphics Inc., Tele-Communications Inc., Time Warner Cable, Turner Broadcasting System Inc. and Virgin Interactive Entertainment. Supporting development of high-speed cable modems are ADC Telecommunications Inc., AT&T Network Systems, General Instrument Corp., Hewlett-Packard Co., Hybrid Networks Inc., Intel Corp., Lancity Corp., Motorola Inc., Northern Telecom, Scientific-Atlanta Inc. and Zenith Electronics Corp.

Telephone companies

Despite this powerhouse cable-TV lineup, the telephone companies may have an ace up their sleeves. They are adapting an AT&T Microelectronics 16-CAP, or carrierless amplitude/phase modulation, technology to carry multimedia data into the home over existing copper at speeds to 52 Mbits/sec.

Chips based on this multipoint broadband access technology would be built into subscribers` set-top boxes and telephone companies` curbside hubs, and route different data/video programs to multiple home TVs and personal computers (see Lightwave, December 1995, page 1). This is done using a combination of three technologies: asynchronous transfer mode, or ATM, switched communications; CAP data modulation and switched digital video.

However, Ronald O. Brown, an independent communications consultant based in Melrose, MA, cautions: "One problem with this approach is that the [telephone companies] don`t have a uniform cable plant into the home as far as quality goes. If they had good-quality copper everywhere, they could get higher speeds than are now possible. Over a good cable plant right now, they can probably get 1.5 Mbits/sec into the home.

"While 1.5 Mbits/sec does not sound like much when compared with the 27 to 40 Mbits/sec promised by cable companies, it`s actually more than adequate," Brown says. "It could easily shoot compressed video into your home," he explains. "Also, the cable companies` approach has been to shoot all signals into every home. For two-way information services, you don`t have to do that and don`t really need the bandwidths cable providers are promising. For example, if a house is pulling in three different TV channels and also doing full-speed Ethernet access, you`re still not close to the speeds being quoted for cable modems. All players in this market need to ask how much bandwidth is really needed at any given time."

As with the cable modems, telephone companies` MBA systems are based on existing high-speed modem concepts, according to Gerry Pepenella, transmission integrated circuit marketing director for AT&T Microelectronics. This means that both cable providers and telephone companies will soon be able to get products into consumers` hands," adds Brown. "For all intents and purposes, the products and technologies already exist," he says, "so getting new versions out the door is essentially a trivial job."

Backing both the cable-TV companies and telephone companies is AT&T Network Systems in Morristown, NJ. It is adapting its hybrid fiber/coaxial-cable technology as a cable-TV and telephone company network-upgrade tool. This HFC-2000 cable enables service providers to carry interactive games, TV programs, Internet web pages and digital video to many more homes than is possible with coaxial cable alone.

According to Marty Plapa, distinguished member of the technical staff at AT&T Bell Laboratories, Denver, CO, HFC-2000 uses fiber as a backbone to carry traffic to subscriber neighborhoods. Coaxial cable then distributes individual data streams into subscriber homes. "The system provides a pool of bandwidth to subscribers," Plapa says, "and the pool can be increased broadly across the entire service area or targeted to local hot spots.

"Our initial push with HFC-2000 will be to help the cable operators who are upgrading their networks with fiber," he adds. "Initially, their information networks will have to pass more homes than will [telephone companies`] networks. That`s because a larger number of homes will probably subscribe to telephone company services at first."

This suggests a stronger initial role for HFC-2000 technology in cable-providers` networks, where a single hybrid fiber/coaxial-cable fiber backbone can carry services into many sparsely distributed neighborhoods. But several telephone companies--Bell Atlantic, GTE, Pacific Bell, SNET, Southwestern Bell Telephone and U.S. West--are also testing HFC-2000 in information networks serving hundreds of thousands of homes.

A marketing slugfest

Will either cable-TV or telephone companies have an advantage in the broadband information battle? According to statistics released at the Western Cable Show, only 10% of cable-TV providers` coaxial-cable networks can bring data out of subscribers` homes. AT&T`s Plapa agrees that cable providers` networks will probably remain more broadcast-oriented than will telephone companies`, which are based on switched two-way communications. This would suggest a home-court advantage for the telephone companies, which are already set up for two-way communications with every home in the country.

But this is not yet two-way broadband communications. When it comes to raw bit-pushing, Plapa gives cable operators the edge. "They already have a broadband infrastructure in place," he explains, "and many of them are upgrading for even higher bandwidths. So they may be able to offer broadband information distribution more quickly than telephone companies."

Brown, however, believes that this battle will favor the best marketer. "Unfortunately, the telephone companies are not good at marketing and promotion," he explains. "About the only thing [these companies] have going for them in the marketing area is the tremendous animosity currently felt toward cable-TV companies. Cable providers have learned nothing from the telephone companies` discovery that monopoly practices anger people."

Brown adds, however, that cable-TV companies are much more experienced and creative at marketing and hustling. "So as a bottom line, I`d give the cable companies a better probability of success, in spite of telephone companies` greater engineering capabilities and resources," he says. q

Dave Powell writes from Winchester, MA.

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