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Information contained in this news release is current as of the date of the press announcement, but may be subject to change without prior notice.
November 22, 2018
Nippon Telegraph and Telephone Corporation
Oki Electric Industry Co., Ltd.
The Telecommunication Technology Committee
- Enhancing reliability based on Recommendations for design, testing, and quality estimation of measures designed to mitigate soft errors caused by cosmic rays -
ITU-T which is the United Nations specialized agency approved standards about soft errors*1 affecting telecommunication equipment on November 13, 2018. These standards stipulate the design, testing and quality estimation methods and reliability requirements concerning measures designed to mitigate malfunctions (soft errors) in telecommunication equipment on the ground chiefly caused by cosmic rays.
To develop these standards, NTT, Fujitsu, Hitachi, NEC, and Oki jointly developed draft Recommendations at "the Ad Hoc Committee on Soft Error Testing (SOET_Adhoc)" formed by TTC, and have driven efforts at ITU-T SG5*2 meetings, with the cooperation of Orange, to have these drafts adopted by ITU-T.
The adopted standards will help to establish networks that are more highly reliable based on the requirements governing measures against soft errors.
In recent years, the number of soft errors caused by cosmic radiation neutrons has been increasing gradually even in telecommunication equipment located on the ground.(Figure 1) The soft error disappears as soon as the semiconductor device concerned is restarted or the data concerned are overwritten. Even though a soft error in data can cause a malfunction or system outage, it is difficult to reproduce such a transient error and identify the cause. Since a soft error can have a serious impact on the user, it is a major headache for system operators. Telecommunication equipment is designed so that such malfunctions do not affect network services. However, because soft errors are difficult to reproduce, they were not sufficiently verified at the development stage.
Recently, however, it has become possible to measure the influence of soft errors on telecommunication equipment using a compact accelerator-driven neutron source*3. This measurement makes it possible to determine the influence of soft errors and take preventive measures in advance before vendors sell products and telecommunication carriers introduce telecommunication equipment into operating networks. While it has become possible for carriers to improve network quality dramatically by mitigating soft errors at the stages of equipment development and introduction, there is a need for requirements that serve as the benchmark for methods and evaluation of countermeasure.
Figure 1 Mechanism of soft error occurrence
Against this background, at the October 2015 meeting of ITU-T SG5, commencement of a study program on soft errors in telecommunication equipment was approved with the intention of defining requirements on measures against soft errors, ranging from design to evaluation and quality. The SOET_Adhoc member companies worked together and developed draft Recommendations. ITU-T has now approved these Recommendations.
The Recommendations stipulate the design, testing and quality estimation methods and reliability requirements concerning soft errors. They include benchmarks based on which vendors and carriers can select measures against soft errors that are appropriate for the required reliability level.
The soft-error-related standards approved by ITU-T consist of five Recommendations and a supplement. Figure 2 shows an overview of the Recommendations.
Figure 2 Overview of soft error Recommendations
Each Recommendation or supplement defines the following items:
It is expected that widespread deployment of telecommunication equipment that satisfies the requirements defined in these Recommendations will improve the reliability of telecommunication services.
|K.124||Overview||Overview of particle radiation effects on telecommunications systems
|K.130||Test||Neutron irradiation test methods for telecommunication equipment
|K.131||Design||Design methodologies for telecommunication systems applying soft error measures
|K Suppl.11||Supplement||Supplement to K.soft_des - Soft error measures for FPGA
|K.139||Requirements||Reliability requirement of particle radiation effect for telecommunication systems||November,2018|
|K.138||Quality estimation||Quality estimation methods and application guidelines for mitigation measures based on particle radiation tests||November,2018|
Information Network Laboratory Group, Planning Department, Public Relations Section
Public and Investor Relations Division
Systems & Services Business Division, E2E MONOZUKURI Innovation Operation, Service & Platform Business Development Department,
Corporate Communications Division
Public Relations Division
Vanessa Clarke, Director, Group Press Office
Kaoru Yoshida, Director, Standardization
Hitachi, Ltd. (TSE: 6501), headquartered in Tokyo, Japan, delivers innovations that answer society's challenges, combining its operational technology, information technology, and products/systems. The company's consolidated revenues for fiscal 2017 (ended March 31, 2018) totaled 9,368.6 billion yen ($88.4 billion). The Hitachi Group is an innovation partner for the IoT era, and it has approximately 307,000 employees worldwide. Through collaborative creation with customers, Hitachi is deploying Social Innovation Business using digital technologies in a broad range of sectors, including Power/Energy, Industry/Distribution/Water, Urban Development, and Finance/Social Infrastructure/Healthcare. For more information on Hitachi, please visit the company's website at http://www.hitachi.com.