NTT's Secure Computing Technology adopted as ISO International Standard
Secure computing technology to speed up data utilization and protect privacy

Tokyo - Mar. 21, 2024 - NTT Corporation (NTT) has been promoting and leading R&D and standardization activities for many years¹ and NTT's proprietary technology was adopted in the document the International Organization for Standardization (ISO) has issued ISO/IEC 4922-2:2024. The document stipulates the use of secret sharing technology for the secure computation technology that can process data while keeping it encrypted.
　This standardization follows ISO/IEC 4922-1:2023², which defines the terminology of secure computation in general, and standardizes the implementation secure computation based on a specific standard. NTT has been working on a group of technologies called "secure computation using secret sharing" for many years, which is characterized by high speed. This time, basic parts such as addition, multiplication, and random number generation have been standardized, and NTT's original technology, multiplication, has been adopted as a standard technology.
　Based on this standard, NTT will continue to contribute to the social implementation and standardization of secure computing technology.

1. Background

In recent years, there have been great expectations for the use of data across organizations and sectors in order to improve operational efficiency and create new value, as exemplified by digital transformation. On the other hand, if the data handled includes data related to personal privacy or corporate profit or management, data sharing is avoided due to the risk of information leakage and implementation has not progressed. Therefore, secure computing technology is attracting attention as a technology that promotes the appropriate management and utilization of data.
　NTT has long been engaged in the research and development of secure computing technology that enables data to be encrypted and processed without being decrypted. The disadvantage of secure computation is that it is slower than usual because the processing is done while encrypting. Therefore, we focused on secure computation using secret sharing technology³, which is the fastest among several known methods for constructing secure computation. By further speeding up these methods, we have achieved practical processing speed⁴ and contributed to the realization of the advanced secure computation service "SeCIHI®"(Secure Computation and Information Handling Interface)⁵.

2. Significance of this standardization

This standard specifies a method of secure calculation using secret sharing, which makes it possible to implement secure computation in accordance with the standard.
　The newly issued standard specifies a basic calculation method for secure computation using secret sharing. These include addition, subtraction, generation of random numbers, and multiplication while data is kept encrypted. Although four methods of multiplication are specified, NTT's original method of multiplication is specified as the most efficient method of multiplication, especially when using secret sharing, which is suitable for secure computation, called replication secret sharing.
　Multiplication is also heavily used in statistical analysis, AI model building, and so on, making it faster to perform these analyses while encrypted.

Figure 1 Scope Secure Computing Technology Standardization

3. Outlook

NTT will continue to work to realize a society that protect private data through research and development of secure computing technologies, and will contribute to the promote social implementation as one of the key functions of IOWN⁶ to create new value. (Figure 2)

Figure 2 Creating New Value Through Secure Computing Technology

< Reference and Terminology >

¹ISO/IEC 4922-2:2024 Information security - Secure multiparty computation - Part 2: Mechanisms based on secret sharing https://www.iso.org/standard/80514.html

²Contribution to the first ISO for Secure Computation Technology for data utilization and privacy protection
https://group.ntt/en/newsrelease/2023/09/15/230915a.html

³NTT's Secret Sharing Technology adopted as the first international standard
https://group.ntt/jp/newsrelease/2017/10/23/171023a.html

⁴Offering the world's first "Secure Computation AI software capable of training and inferencing with key algorithms in four major categories of AI"
https://group.ntt/en/newsrelease/2023/01/23/230123a.html

⁵Start of "SeCIHI" service that enables secure computation in the cloud
https://www.ntt.com/about-us/press-releases/news/article/2021/0819.html

⁶IOWN Initiative (Innovative Optical and Wireless Network):
An initiative for networks and information processing infrastructure including terminals that can provide high-speed, high-capacity communication utilizing innovative technology focused on optics, as well as tremendous computational resources. This is done in order to overcome the limitations of existing infrastructure with innovative technologies, optimize the individual with the whole based on all available information, and create a rich society that is tolerant of diversity.
https://www.rd.ntt/e/iown/

About NTT

NTT contributes to a sustainable society through the power of innovation. We are a leading global technology company providing services to consumers and business as a mobile operator, infrastructure, networks, applications, and consulting provider. Our offerings include digital business consulting, managed application services, workplace and cloud solutions, data center and edge computing, all supported by our deep global industry expertise. We are over $97B in revenue and 330,000 employees, with $3.6B in annual R&D investments. Our operations span across 80+ countries and regions, allowing us to serve clients in over 190 of them. We serve over 75% of Fortune Global 100 companies, thousands of other enterprise and government clients and millions of consumers.