Internet access rockets over CATV fiber

Internet access rockets over CATV fiber


Continental Cablevision of Los Angeles, the nation`s third-largest cable-TV operator, reports that its customers in the Boston area are now participating in a field trial for high-speed Internet-access service that could grow nationwide within three years. Using cable modems from LANcity Corp., Andover, MA, about 200 of the cable-TV provider`s customers are linking to the Internet at 10 megabits per second over Continental`s existing hybrid fiber/coaxial-cable network.

Continental is not entering the Internet-services business, but is instead connecting its test sites to BBN Planet Corp., a Cambridge, MA, Internet gateway provider. Through it, Continental`s subscribers can browse the World Wide Web and send and receive global e-mail messages.

According to Ed Holleran, Continental Cablevision Inc.`s vice president of business development, most of the 200 Boston test sites are residential. "But a few businesses are also testing the Internet service for carrying commercial local area network traffic," he says.

Cable-TV networks are currently the only practical way to offer such high-speed data services, says Gary Arlen, president of Arlen Communications Inc., a Bethesda, MD, Internet-services researcher. "The value of cable networks` fiber/coaxial-cable pipelines is that users can access and move bigger data files faster, including graphics and video files."

In fact, this increased speed was one of several reasons why the Boston-based New England Cable News service recently moved its network from satellites to Continental Cablevision`s terrestrial network. "We`ve been thinking about doing this for some time," explains NECN President Philip S. Balboni. "We started considering the switchover after we outlasted two dying birds [satellites] and saw another ready to shut down in 1997. Also, since satellites have a global reach, they tend to be a bit expensive for a regional business like ours."

So one year ago, NECN cut over to Continental Cablevision`s network to reach 850,000 subscribers in 407 New England towns and cities. And like Continental, NECN has digital services in mind for this terrestrial pipeline. "We hope to offer an interactive news service," Balboni explains, "which [would allow] users to access and filter news text, and search and screen video news archives."

Compared with the 10-Mbit/sec speeds in Continental Cablevision`s Boston trials, telephone company networks are currently much slower, adds consultant Arlen. They usually offer Internet access through either telephone-line modems running below 30 kilobits per second or integrated services digital network, or ISDN, basic-rate-interface digital services limited to 128 kbits/sec.

NECN`s Balboni illustrates this speed limitation. "America Online recently launched its own Digital City Boston news service over NECN`s network," he explains. "Since most users access America Online through analog modems, they`ll be able to get video freeze frames, but our higher-speed interactive service will deliver full-motion video."

However, the telephone companies will catch up: They are building systems capable of 52-Mbit/sec transmission into the home over existing copper telephone wire. This multipoint broadband access technology could support different data and video programs going to multiple user personal computers and televisions.

But due to the varying condition of telephone companies` copper networks, this 52-Mbit/sec potential bandwidth probably will fall to 1.5 Mbits/sec in practice, says Ronald O. Brown, an independent communications consultant based in Melrose, MA. "This 1.5-Mbit/sec transmission may not sound like much against what the cable providers are promising," explains Brown, "but it is quite adequate for two-way information services."

Fiber upgrades needed

Still, cable-TV providers can`t just leap into high-speed digital services without their own advance preparation, Arlen adds. "Cable-TV plants often are not as sturdy as telco networks," he explains. "It`s one thing to lose a second or two during a rerun of Laverne and Shirley, but glitches in data traffic can be catastrophic. So the cable-TV industry as a whole is upgrading its facilities for digital traffic."

In fact, Continental Cablevision did just that, according to Holleran. "Before the Boston test, fiber didn`t penetrate as deeply as necessary into our test towns of Newton, Needham, Wellesley, Watertown and Cambridge," he explains. "So we`ve been extending it and upgrading the fiber nodes serving customers." This upgrade process also included new LANcity cable modems in trial homes, and digital routers and Ethernet switches in Continental`s local head-end offices.

In the Boston test, fiber carries traffic from headend offices to fiber nodes serving user sites. From the fiber nodes, coaxial cable runs into user sites for normal cable-TV, and a second coaxial line splits off to the user`s cable modem and PC.

Although its market test currently reaches only 200 sites, Continental Cablevision plans to rapidly expand the Internet-access service. "By the end of this year, hybrid fiber/coaxial-cable will offer Internet access to 300,000 of our 1.2 million New England subscribers," says Holleran. "And in another three to four years, all of our 4.2 million subscribers nationwide should be able to reach the Internet over our network." Holleran estimates that when the service becomes commercially available, it should cost subscribers about $25 to $40 per month.

In the near future, competition will only heat up in high-speed digital services. Passage of the Telecom Act allows cable-TV providers, telephone companies, and information services to invade each others` turf (see Lightwave, pages 3 and 4). As a result, Continental Cablevision`s Internet-access services will be the first of many offered by a bewildering variety of suppliers. q

Dave Powell writes from Winchester, MA.

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