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ERATO and Japan's Dreams of Future Technology

Victor Rehn

The 10-year-old ERATO program is one of Japan's most innovative programs for
moving the frontiers of science toward advanced technology.

Manufacturing Science

State of the Art in Japanese Computer-Aided Design Methodologies for Mechanical Products: Reports on Individual Visits to Companies and Universities

Daniel E. Whitney

This is an appendix to an earlier summary report published in the first issue of 1992
on the Japanese use of computers in design of mechanical products. Detailed
information on the author's visits to companies and universities is presented.

Materials Science

Assessment of Carbon-Carbon Composite Research in the Far East
Robert A. Meyer

The current status of carbon-carbon composite research is assessed and future
directions of foreign research efforts are estimated.

Ocean Science and Engineering

First Workshop on the Yellow Sea Experiment (YESEX-1)
Pat Wilde

The Korea Ocean Research and Development Institute (KORDI) has proposed
the Yellow Sea become an international full-size test laboratory as an outgrowth
of the Korean program of real-time coastal monitoring and prediction initiated in
1991. To test the feasibility of this concept and to bring together workers and
knowledge about the Yellow Sea, KORDI sponsored YESEX-1.

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231

Superconducting Magnetohydrodynamic Ship Propulsion

A Worldwide Research Effort

Thomas F. Lin

This article summarizes observations and opinions of many of the participants of
MHDS'91, the International Symposium on Superconducting Magnetohydrody-
namic Ship Propulsion. The most significant development is the near-completion
of the MHD experimental ship YAMATO-1.

Physics

Synchrotron-Radiation Research in Japan: Preparation for Spring-8
Victor Rehn

Spring-8, a huge, 8-GeV storage ring and associated synchrotron-radiation
facilities, is scheduled for commissioning on 1 April 1998. This facility is described,
and the Third International Synchrotron-Radiation Symposium is reviewed.

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237

243

Cover: A bird's eye view of the Spring-8 facility, which will be Japan's newest and largest synchrotronradiation facility. Groundbreaking took place in November 1991 in Harima Science Garden City, located in the mountains west of Kyoto. For more information on SPring-8, see Victor Rehn's article on page 243. Photo courtesy of the JAERI-RIKEN SPring-8 Project Team, Yukio Sato, Deputy Director General.

ASIACRYPT '91

The Asiacrypt '91 conference was held in Fujiyoshida, Japan, at the foot of Mt. Fuji, from 11-14 November 1991. It was cosponsored by the International Association for Cryptologic Research (IACR) and the Institute of Electronics, Information, and Communication Engineers [IEICE, a Japanese engineering society similar to the Institute of Electrical and Electronics Engineers (IEEE)] and was devoted to the presentation of the latest research results in cryptology. It attracted about 190 participants, roughly 120 from Japan and the others from over a dozen countries.

The technical program consisted of 4 invited lectures and 39 contributed ones. The proceedings will be published in 1992 by Springer in their Lecture Notes in Computer Science series under the title "Advances in Cryptology ASIACRYPT '91." The editors will be the two program cochairmen, H. Imai of Yokohama National University (imai@imailab.dnj.ynu.ac.jp)

and

R. Rivest of the Massachusetts Institute of Technology (MIT) (rivest@theory.lcs.mit.edu).

The lectures covered all aspects of modern cryptology, although there was heavier representation than at some of other recent meetings on cryptanalysis and construction of classical privatekey cryptosystems.

Sang-Jae Moon of Kyung Pook National University in Korea presented an invited lecture titled "Research Activities on Cryptology in Korea." This lecture turned out to be a survey of cryptologic activities in South Korea, Taiwan, and to some extent Japan.

SIBRIEF

Scientific Information Briefs

Although some South Korean and Taiwanese cryptologists have been attending Crypto and Eurocrypt meetings for years, and have occasionally contributed papers to those conferences, the recent rapid growth of interest in cryptology in their home countries is not well known. Some of the Korean meetings have attracted more than 100 participants, but it appears that these were more instructional meetings than research conferences. Participants from Taiwan and South Korea attributed the considerably greater level of activity in Korea to the support that country's government has given to cryptology work.

There has been substantial unclassified work on cryptography in China in the last 10 years. Many cryptologists from that country have attended Western conferences and visited European and American universities. Their work was well represented among the papers accepted for the Asiacrypt '91 program, but unfortunately because of visa and financial difficulties few of the authors were able to attend, and most of their lectures were canceled. There does not seem to be any survey of cryptologic research in China similar to that of Prof. Moon for Korea and Taiwan.

Some of the Japanese work in cryptology is well known in the United States, since Japanese scientists have frequently attended meetings in the West, have presented papers, and have published in English language journals. However, the full extent of this work is not appreciated.

There were demonstrations of cryptographic products at Asiacrypt '91, both hardware and software. It appears that the civilian market in Japan for

cryptographic products is still undeveloped compared to those in Europe or North America. Fewer products are available, and market demand is small so far. There are some sophisticated products, especially from companies such as NEC and NTT, which have been involved in cryptologic research and development (R&D) work for a long time. However, sales do not appear to be substantial yet. The companies demonstrating their products included most of the large integrated electronics companies, and they appear to be committed to work in this area, as can be seen by the number of people they have working in it. There were no small companies represented that are so common in Europe and North America, consisting of a few people, and often started by a college professor. On the other hand, there were presentations by some companies that in the West would not have been expected to engage in sophisticated R&D.--Andrew Odlyzko, AT&T Bell Laboratories

JAPAN'S PROGRESS ON THE INTEGRATED SERVICES DIGITAL NETWORK (ISDN)

Broad-band ISDN, high speed communication, is coming to Japan. Companies are preparing products for the time when, not if, this will be widely available. The actual date this reaches large numbers of Japan subscribers is less important than the sense that it is moving inexorably forward. (Now there are digital telephone boxes popping up in Tokyo, at least, with ISDN plugs for computer, fax, etc.)

NTT is the major agent, and its monthly NTT Review is full of articles about applications.

The current narrow-band integrated services digital network (N-ISDN) went into operation in Japan in April 1988 with the implementation of NTT'S INS Net-64, which has a 64-kbit/s transmission capability. In June 1989 NTT introduced INS Net-1500, with a much higher speed of 1.5 Mbit/s. INS Net-1500 allows multimedia communication, including teleconferencing, and it is possible to transmit a document page via fax in only 3 seconds. INS Net started with 29 users and 114 subscriber lines. Total INS Net-64/1500 subscriber lines have now passed the 60,000 mark. NTT claims that the number of ISDN circuits contracted for is expected to have reached 80,000 by April 1992, including about 2,000 areas in Japan.

With a maximum transmission speed of 1.5 Mbit/s, N-ISDN service is limited to the transmission of voice, low- and medium-speed data, still pictures, and simple moving images. Broad-band ISDN (B-ISDN), with transmission speeds as high as 620 Mbit/s, will be able to handle high-density media such as high-definition television (HDTV), cable TV, and videotex. The asynchronous transfer mode (ATM) technique, key to B-ISDN switching, increases both speed and frequency bandwidth by a new transmission protocol. In N-ISDN, telephone, fax, video, and TV signals are divided and passed through several different switching systems and then re-combined just before reaching the receiving terminals. ATM technology integrates these into a single net. The individual ATM transmitting terminal chops the information waves into cells of fixed lengths, assigns labels to them, and sends the "wavelets" to the net. When these cells arrive at the receiving end, the various information signals, grouped by assigned label, are directed to appropriate terminals: telephones, computers, or TV conference terminals.

Although ISDN is still in the fledgling stage, Japanese industry is busy preparing for the second-generation B-ISDN, which is up to 2,000 times faster than the existing ISDN. In 1990, the International Telegraph and Telephone Consultative Committee (CCITT) introduced formal guidelines for B-ISDN. The Japanese telecommunications provider, NTT, plans to have B-ISDN operational for commercial users in 1996 with three distinct features: ATM net, optical-fiber communication, and "opticalization" of components. The new technologies will begin to replace the existing ISDN infrastructure around the year 2000 and is planned to be completed by 2015. It is claimed that optical fiber will reach cost parity with copper by 1995.

New 10-Gbit/s transmitting and receiving equipment is being developed by Toshiba for commercial availability in 1996. This equipment will use one optical fiber to carry 120K telephone lines simultaneously up to 80 km. It will feature several gallium arsenide integrated circuits (ICs) capable of processing information and is claimed to be three to five times faster than conventional silicon ICs. NTT has also successfully carried out a 10-Gbit/s successfully carried out a 10-Gbit/s optical transmission experiment using dispersion-shifted single-mode optical fibers with a combined length of 1,260 km that are installed in a commercial route between Tokyo and Hamamatsu (route length 326 km).

NTT's Large-Scale Integration (LSI) Laboratory recently introduced two new types of LSI chips for use with optical communications in B-ISDN. The FIFO (first in, first out) LSI chip is intended for ATM use, and the time-slotconverter LSI chip is designed for use in circuit divisions and multiplexing. The FIFO LSI chip uses 0.8μ BiCMOS technology on a single chip to upgrade processing speeds from the 80 Mbit/s of conventional FIFO to 250 Mbit/s, while reducing power consumption from

20 W to 0.8 W. The NTT system also involves an optical switching system based on VSTEP (vertical-to-surfacetransmission electrophotonic device) technology, developed by them. The prototype switching system includes a superhigh-speed 4x4 (four inputs, four outputs) cell-fluting circuit that makes it possible to switch optical signals without converting them to electrical signals and an optical buffer memory that holds input signals until they are placed on the output lines. NTT's experiments, said to be the first of their kind, verified the feasibility of high-speed optical throughput switching, required to achieve 1-Tbit/s ATM switching for B-ISDN. In the area of standardization, NTT has developed a B-ISDN quality standardization system called "SQUARE" (Subjective Quality Assessment REference system) capable of measuring and standardizing both sound and video quality through simulation. NTT is seeking to establish SQUARE as an international standard for B-ISDN quality control through the CCITT.

Fujitsu has developed FLM2400, a synchronous digital hierarchy (SDH) optical telecommunications device for B-ISDN with a transmission speed of 2.4 Gbit/s. NTT also claims to be working in this area. SDH makes it possible to directly multiplex and cross-connect channels that have different capacities, allowing greater freedom and operational flexibility. In the B-ISDNcompatible terminals arena, Fujitsu has developed Monster, a multimedia workstation with an image processing capability, and has also announced a plan to produce an HDTV signal compression system within 2 or 3 years that would be able to vary transmission speeds over B-ISDN line by 60 Mbit/s to 130 Mbit/s. Since HDTV signals require extremely high transmission rates (approaching 1 Gbit/s), the optical fiber line over which the signals are sent can become too crowded

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