Japan moves toward converging technologies in fiber tests
PAUL MORTENSEN
Japan`s vision of its digital communications future depends on three inseparable code words: fiber optics, multimedia and information-infrastructure. Recently, however, with Nippon Telegraph & Telephone Corp., Tokyo, reshaping its communications image, the company has started to emphasize multimedia and the anticipated convergence of audio, video and computing. In line with this, the company will start a new round of tests for wireless personal handy-phones and their associated fiber-access technologies.
As Japan moves toward a domestic information superhighway, some industry analysts forecast a fiber installation slowdown, due to a policy shift that favors wireless technologies over optical-fiber networks. Of course, the proposed nationwide fiber network is still favored by the government, but it has become clear that the project is the product of conflicting components, which are starting to slow its progress.
Numerous factors are involved, including a "catch-up mentality"--a perceived backwardness of networking in Japan compared to the United States. This perception is illustrated in the Japanese press by daily, weekly and monthly reports, newspaper articles, and books that focus public attention on this problem. Another explanation is that the implied competitive threat provides the external pressure necessary to speed up the decision-making process and force things to a conclusion.
Other factors include the following:
Producer motivations, which stress potential revenues and jobs generated by the network and the fostering of competitiveness among Japanese fiber-optic cable makers
Top-down, not bottom-up or consumer-driven, development of fiber-related services and products
Bureaucratic rivalry between the Ministry of International Trade and Industry and the Ministry of Posts and Telecommunications, which sponsor different industry groups
An artificial completion schedule, which alternates between the years 2010 and 2015.
Meanwhile, the emerging wireless option is symbolized by the home-grown personal handy-phone service, which is scheduled to start nationwide this summer. This service could generate a widespread response from Japanese consumers.
Analysts also predict the convergence of future fiber networks to create seamless, low-cost telecommunications for subscribers. At present, the personal handy-phone service is a personal communications service that will be a close, but not a full, competitor with the cellular phone system.
Unlike cellular phones, however, personal handy-phones cannot be used in moving vehicles. They will be fully interconnected with the public switched telephone network and will provide cellular-like services for a basic charge of 2000 to 3000 yen per month (much less than the cellular phone), with air-time charges of 30 to 50 yen per three minutes. Initially, the personal handy-phone system will not have hand-over capability.
Despite the system`s limitations, entrants are predicting that it will be very popular. Three companies will participate: Nippon Telegraph & Telephone, Daini Denden Inc. and TTNet. Both Daini Denden and TTNet can use their long-distance fiber cables to link personal handy-phone subscribers between major cities, but they will have to pay for connection charges for Nippon Telegraph & Telephone`s local loop. This year, arguments over favorable connection charges have required the mediation of the Ministry of Posts and Telecommunications.
For personal handy-phone service, TTNet, whose major shareholder is Tokyo Electric Power Company, hopes to maximize the use of its fiber leased lines within Tokyo and other cities and minimize the need to pay Nippon Telegraph & Telephone.
In support of the new system, Nippon Telegraph & Telephone is starting the third phase of tests of its visual, intelligent and personal communications services. The company has already tested multimedia on wired networks. In the first phase, it tested multimedia on narrowband-integrated services digital network; in the second, it stressed optical subscriber and asynchronous transfer mode methods. The third round will focus on new personal multimedia communications services that use wireless personal handy-phones; access systems such as fiber radio transmission will also play a part. The tests are divided into terminal-type and network-type personal multimedia services. They differ from earlier trials, which involved videoconferencing and other services, because they will test technology that the average person could find immediately useful.
Unlike the relatively narrow bandwidth of the cellular phone, the personal handy-phone service terminal allows 32-kilobit-per-second digital communications with base stations, which are installed on top of telephone boxes and buildings throughout the city. Projected terminal-type services are data and video communications through personal handy-phone terminals. Network-type services will allow the network to detect a user`s location by means of personal handy-phone terminals and to provide other user-adaptive services. Tests by means of personal handy-phone terminals include modem-type non-phone services, such as E-mail and handy-fax; high-speed database access; digital still-picture transmission; and field video. To diversify access networks, Nippon Telegraph & Telephone will develop wireless and satellite communications systems in addition to optical access systems.
Fiber-related tests will include 1.5-megabit-per-second fiber radio transmission--a technology that converts a microwave signal to light and transmits it via optical fiber--and digital video transmission with the Motion Picture Experts Group-1 standard for coding. The MPEG standard compresses and regenerates moving pictures with sound at a coding rate of 1.5 Mbits/ sec --with picture quality equal to that of VHS.
The trend toward more economical means of communication is clear in Nippon Telegraph & Telephone`s recent report on research and development for multimedia. The keyword is affordability. Research and development will emphasize the development of more economical modes for personal handy-phone and integrated services digital network services. Other aims are to drive down optical-cable costs to a par with metallic cable by the year 2000; to diversify access networks by developing wireless and satellite communications in addition to optical access systems; and to develop asynchronous transfer mode connectionless communications technologies and large-capacity node technologies for highly marketable Internet-type multimedia communications nodes. These technologies will, in turn, enable more connectionless-type communications services.
These modified aims contrast with the company`s previous (but still valid) goal of a nationwide fiber network by 2010 and those of Japan`s large electronics companies, which for many years have developed expensive fiber-based equipment and innumerable consumer products to justify the bandwidth of a digital telecommunications web that supplants the existing telephone network. q
Paul Mortensen writes from Tokyo.