Yokogawa Electric Corporation has developed a prototype of an ultra-fast 40-Gbit/s optical packet switch using compound semiconductors and fast electronic circuit technologies that is unrivalled in its switching speed and small size. With this innovation, Yokogawa now enjoys the prospect of being able to commercialize optical packet communications for use in local area networks (LANs) in fiscal year 2005, 10 years earlier than was originally anticipated. The company will accelerate its development of product versions of 40-Gbit/s optical packet switches, and will initiate the optical communications equipment business as early as fiscal year　2005, with these switches as its core product.

Yokogawa will present a paper and a demonstration of this latest achievement at OFC 2004, the world’s largest optical communications conference and exhibition, to be held in Los Angeles starting February 23.

OFC 2004 official site: http://www.ofcconference.org/
Paper presentation: No. MF53 (February 23, 17:30 - 19:00 poster session)
Demonstration: Booth No. 2639: ANDO/YOKOGAWA booth (from February 24 to 26)

Overview
The 40-Gbit/s optical packet switch is comprised of an optical switching device that switches optical packet signals at extremely high speeds without temporarily converting them into electric signals and an optoelectronic integrated circuit that controls the optical switch based on destination information carried by the optical packet signals. The optical switching device switches optical paths at as quickly as 2 nanoseconds, or 2 billionths of a second, by turning on/off the current input to the compound semiconductors.  This is the world’s fastest such device using the current injection technique, and it is one million times the speed of movable mirror based optical switches. As for the  optoelectronic integrated circuit, this combines a high-speed photodetector device that reads the destination information in the headers of the optical packets with a fast electronic circuit that processes that information.  It controls the optical switching device according to the read destination information. 

The optical packet switch prototype is much smaller than other optical packet switches that have already been released, with a footprint that is approximately the same size as an A4 sheet.

Significance of This Technology
The 40-Gbit/s optical packet switch is the core technology in optical packet routers, which are the most important component in next-generation ultra-fast photonic networks. Using this technology, 10 personal computers can connect to a server and simultaneously download data equivalent to a 2-hour movie in just 10 seconds. Achieving the same speeds with existing optical communications technologies requires a direct connection between the server and user terminals.  This method has not taken off mainly because it cannot flexibly connect multiple terminals.

The Current Optical Communications Market
Although the optical communications market has been sluggish the last few years following the bursting of the communications bubble that originated in the US, data compiled by the Ministry of Public Management, Home Affairs, Posts and Telecommunications (MPHPT) indicates that the number of subscribers to DSL, FTTH, and CATV broadband Internet services increased 70 percent from 2002 to 2003.  At this rate of growth in broadband traffic, there is a looming possibility that a shortfall in communications capacity may occur in four to five years.  To set the stage for the coming age of next-generation, large-capacity communications, the MPHPT has established a Next Generation IP Infrastructure Study Group and convened its first meeting on February 3, 2004.  Heavy capital investment of approximately 10 trillion yen is expected in this field in the near future.

In addition to the nation’s backbone network , the LANs used by businesses, municipalities, and other entities will run short of communications lines sooner or later.  The time is fast approaching when LANs will routinely handle exponentially larger amounts of data, including images.   The construction of ultra-fast 40-Gbit/s networks will be particularly important for Internet data centers (IDC) and broadcasting stations which must deal with massive volumes of data.

Yokogawa’s Approach to the Communications Business
This new 40-Gbit/s optical packet switch represents a major step forward for Yokogawa’s optical network business.  This business will focus first on developing the huge LAN market including IDCs, broadcasting stations, and enterprises, and it will also develop the market for peripherals and other high-speed devices.

In addition, Yokogawa has moved ahead of the competition by successfully developing driver modules for optical modulators, photodiode modules, and other technologies that will be vital to the realization of 40-Gbit/s optical transmission systems.  These are key components of laboratory measuring instruments and optical communications equipment, and Yokogawa will continue to nurture their further development as part of the communications modules business.

Overall, Yokogawa estimates that its entire optical communications equipment business, combining the aforementioned two businesses, will be generating annual sales of 100 billion yen by the year 2010.