Computing and multimedia interact
BEN HARRISON
Providing high-speed interactive data services for personal-computer users over fiber-optic coaxial-cable lines and networks is more than a one-company assignment. Indeed, three communications companies are busy pooling their corporate resources in a partnership venture to provide these services.
The partners are AT&T Network Systems, a network provider in Holmdel, NJ; Intel Corp., a microprocessor chip manufacturer in San Jose, CA; and Hybrid Networks Inc., a networking company in Cupertino, CA. This team is delivering high-speed, interactive multimedia services to home personal computers over hybrid fiber/coaxial-cable networks.
The partners have signed three major deals with regional Bell operating companies and have a major trial underway with a cable-TV company.
Services provided by the partnership include online information, electronic banking and shopping, personal financial and travel planning, classroom lessons, games, home office and Internet access. Home users can also access graphics and large files. These services can be delivered to home personal computers at speeds of 27 megabits per second downstream and 128 kilobits per second upstream, according to Bill Payne, technical manager of visual communications network architecture at AT&T Network Systems, Lisle, IL. He notes that the average distance from the cable headend to the home is at most five miles.
Payne says that upstream transmission of these services occurs in the 5- to 40-megahert¥sub-split band. Thomas E. Chapuran, a senior scientist at Morristown, NJ-based Bell Communications Research, confirmed this data in his presentation, "Architecture and Node Side Implications of Delivering Two-way Services over Hybrid Fiber/Coax," at the National Fiber Optic Engineers Conference held in June in Boston.
Chapuran also noted that hybrid fiber/coaxial-cable networks typically reserve frequencies from 54 to 750 MH¥for downstream transmission, including video and narrowband traffic. He explained that upstream transmission is expected to be confined (at least initially) to the 5- to 42-MH¥sub-split band, to avoid interfering with traditional downstream video channel frequencies and to avoid additional costs associated with upstream transmission above 750 MHz.
Comprehensive package
AT&T Network Systems and Intel are offering a comprehensive package of network and customer premises elements to cable-TV and local telephone companies, creating a set of viable two-way, interactive personal computer services that they can deliver over their current and planned broadband networks.
Stan Holcomb, AT&T Network Systems director of business strategy and visual communications, says, "As a result of this team play, we are deploying hybrid fiber/coaxial-cable access telephony networks to Pacific Bell, Southwestern Bell Telephone and Southern New England Telephone." This development reflects the preference of many personal computer users. In a survey released by RKS Research & Consulting in North Salem, NY, 58% of home personal computer users prefer that their local telephone company, instead of the electric or cable-TV utility, provide PC services and support. Image is a factor, according to the survey. Power-company ads still show "guys in bucket trucks" while the local telephone company "tells you how to get on the Internet," says David Reichman, president at RKS.
Despite these user preferences for the telephone company, an AT&T spokesperson in Boston reports that a major contract has been signed with Comcast Corp., a Philadelphia-based cable-TV company, for a broadband network trial to begin in early 1996. This trial will use AT&T`s HFC 2000 broadband access system.
This is the first application of AT&T`s hybrid fiber/coaxial-cable access platform with a cable company. Initial deployment will provide basic telephony services to approximately 1000 Comcast customers. In addition, the system will enable Comcast to offer a variety of services--integrated services digital network data, dedicated data and small business applications--to its customers.
AT&T Network Systems provides broadband networks and end-to-end network integration. Its hybrid fiber/coaxial-cable network broadband access system allows for convergence of telephony with television, leading to interactive multimedia services.
AT&T`s HFC-2000 broadband access system is an integrated hybrid fiber/coaxial-cable network that incorporates a star-bus topology. It uses a single coaxial service cable to carry broadband multimedia services and narrowband telephony services to subscribers in their homes.
Fiber nodes are installed in neighborhood serving areas of 500 to 2000 homes. In addition to combined optical signals transmitted from the host digital terminal, fiber nodes also receive analog cable-TV signals sent from a broadband transmitter over a separate fiber link. The fiber nodes combine the downstream optical signals and convert them to electrical signals for transmission over multiple coaxial-cable trunks. These trunks feed serving areas of 125 to 500 homes. The fiber node also accommodates the upstream signal required for full implementation of interactive services.
Intel`s Cableport cable-adapter technology brings interactive multimedia data services to home personal computers at high speeds via fiber-optic cable. The speeds offered by cable--1000 times faster than telephone modems--make it possible to deliver these services with sound, video and graphics, and response times not possible with standard telephone modems.
According to Avram Miller, Intel vice president for corporate business development, "The intersection of home computing and high-bandwidth communications is creating the first new medium since the invention of television."
The third team player--Hybrid Networks--provides the cable personal computer networking technology, as well as Internet access. Its hybrid fiber/coaxial-cable access system enables a high-speed digital signal to be received by homes, schools or offices using existing cable TV and telephone transmission facilities.
The company`s hybrid fiber/coaxial-cable access system is an asymmetric, split-speed, digital-transmission system. It uses two-way cable-TV distribution facilities to provide connectivity at Ethernet speeds. The cable-TV plant provides only one-way downstream communications, but the hybrid fiber/coaxial-cable access system uses the public-switched telephone networks at modem speeds to provide the upstream communications path.
Hybrid Networks estimates the home personal computer market at 24 million homes. In addition, there are 60 million cable-TV households. The company`s hybrid fiber/ coaxial- cable access system provides access to the Internet, various online services, digital entertainment, home shopping, software distribution and telecommuting applications. q