2017/04/25
Nippon Telegraph and Telephone Corporation
Hitachi, Ltd.
Oki Electric Industry Co., Ltd.
Keio University
KDDI Research, Inc.
Furukawa Electric Co., Ltd.
The six organizations—Nippon Telegraph and Telephone Corporation (headquartered in Chiyoda-ku, Tokyo; President and CEO: Hiroo Unoura; hereinafter "NTT"), Hitachi, Ltd. (headquartered in Chiyoda-ku, Tokyo; President and CEO: Toshiaki Higashihara; hereinafter "Hitachi"), Oki Electric Industry Co., Ltd. (headquartered in Minato-ku, Tokyo; President: Shinya Kamagami; hereinafter "OKI"), Keio University (located in Minato-ku, Tokyo; President: Atsushi Seike; hereinafter "Keio"), KDDI Research, Inc. (headquartered in Fujimino, Saitama; President and Director: Yasuyuki Nakajima; hereinafter "KDDI Research"), and Furukawa Electric Co., Ltd. (headquartered in Chiyoda-ku, Tokyo; President: Keiichi Kobayashi; hereinafter "Furukawa Electric")—have worked on the research topic of "Elastic Lambda Aggregation Network (EλAN) technology" as an advanced research project looking toward 2030 and beyond.
EλAN is a network that transmits optical signals as they are through wavelength selective switches across access (subscriber–central office) and metro (central office–central office) networks, using an adaptive modulation/demodulation OFDM transmission method that improves the utilization efficiency of optical frequencies. It can elastically allocate transmission speeds and optical frequency bands for traffic with different characteristics used by multiple services, such as the internet, business-oriented lines, and mobile communications.
In addition, we pursued the reliability required for such an innovative network by examining optical transmission path control methods and switch technologies, and conducted experiments using a testbed. We have achieved the world's first successful experiment in which, even if a central office device fails and service is interrupted, another central office device located 10 km away automatically reconnects within 10 seconds at the same transmission speed as before the interruption.
This technology is expected to be a foundational technology for access and metro networks that can adapt to the service diversification anticipated beyond 2030. The results of this work will be presented at the exhibition of iPOP2017 (The 13th International Conference on IP + Optical Network), an international conference on optical communications to be held in Kawasaki, Kanagawa, from June 1 to 2.
For the full press release, please see below.