TOSHIBA REVIEW
2009. VOL.64 NO.7

  Special Reports

Information Security Technologies

Research and Development for Integrated Information Security
—From the Viewpoint of Overcoming Contradictions

TSUJII Shigeo

Information Security Technologies Enhancing Social Contributions of Individuals and Organizations
ENDO Naoki / KAWAMURA Shinichi / OHKUMA Kenji
With all activities of both individuals and organizations having become heavily dependent on information systems, safeguarding the security of information systems is now a crucial issue.
Since the early 1980s, Toshiba has been researching and developing information security technologies for application in a broad range of fields including social infrastructure systems, corporate information systems, and semiconductor products. These fields of application are supported by core technologies such as cryptography and digital watermarking. We are making continuous efforts to enhance the social contributions of individuals and organizations by developing these core technologies and solutions.

High-Bit-Rate Unconditionally Secure Quantum Key Distribution
Andrew J. Shields / Zhiliang Yuan
Quantum key distribution (QKD) technology, in which unconditionally secure key distribution is guaranteed based on a physical law, is expected to be a cryptographic primitive in future secure networks. However, it is essential for the technology to be able to be integrated into real communication infrastructures for widespread use.
Toshiba has participated in a field trial of a small-scale QKD network as part of the Secure Communication Based on Quantum Cryptography (SECOQC) Project funded by the European Union, and has successfully demonstrated both secret telephone communications and video distributions between random nodes on a network. Furthermore, using a newly developed single-photon detection device, we have developed a high-bit-rate QKD system that allows key distribution exceeding 1 Mbps under unconditionally secure conditions.

High-Speed Anonymous Authentication Technology to Prevent Dissemination of Personal Data
YOSHIDA Takuya / OKADA Koji
Although about four years have passed since the Personal Information Protection Law was enforced, incidents of personal data leakage from service providers still occur. Conventional anonymous authentication technologies without the use of personal data and identification have been insufficient for practical use due to the issues of efficiency and user revocation.
To overcome these problems, Toshiba Solutions Corporation has newly developed a practical anonymous authentication technology that can achieve high-speed processing of authentication even on restricted platforms such as personal computers, cellular phones, and IC cards, and makes it possible to be applied to a broad range of business models and use cases.

Secure, Compact, and Efficient Algebraic Torus-Based Cryptography
YONEMURA Tomoko / MURATANI Hirofumi
Algebraic torus-based cryptography are a secure, compact, and efficient means of public-key cryptography based on a discrete logarithm problem. Cryptography is essential in the implementation of a network security system, enabling strangers to engage in secure communication via the network without the need for sharing of keys between the sender and receiver.
Toshiba has developed a parameter selection method for algebraic torus-based cryptography from the viewpoints of both security and efficiency. More specifically, we have obtained parameters that can achieve smaller size of the fundamental arithmetic in the algebraic torus while maintaining security. As a result, the speed of algebraic torus-based cryptography is comparable to and the key size is close to those of an elliptic curve-based cryptography.

Automated Security Proofs for Cryptographic Protocols
HANATANI Yoshikazu / MURATANI Hirofumi / OHTA Kazuo
A security proof is a measure that ensures the security of fundamental cryptographic primitives such as public key encryption, digital signatures, and so on. As it convinces all parties concerned of the security of the primitives, it also provides a criterion for the standard cryptographic scheme. Advanced expertise is required to provide security proofs. There is consequently an increasing need for automated security proof technology.
Toshiba and the University of Electro-Communications have performed analysis and improvement of the proof capability of CryptoVerif security-proving software. Experiments with our improved CryptoVerif confirmed that it could successfully prove all examples given by both Bruno Blanchet and ourselves, whereas the original CryptoVerif might fail in a few examples.

Collusion-Secure Fingerprinting Codes for Fair Content Distribution
ISOGAI Taichi / MURATANI Hirofumi
Digital fingerprinting is one of the techniques employed to prevent illegal distribution of digital contents. In the case of illegal distribution, pirate users can be traced and identified from each user's ID embedded in the digital contents. In a digital fingerprinting system, collusion-secure codes are often used instead of common IDs to control infections by pirate users rewriting their IDs. However, conventional collusion-secure codes require very long code lengths in order to prevent failure to trace pirate users as well as the possibility of false charges.
Toshiba has developed a technique that can reduce the length of collusion-secure fingerprinting codes to about 1/15 to 1/20 compared with the conventional code length by improvement of the tracing algorithm and other optimizations, and is promoting the practical application of a digital fingerprinting system incorporating this technique.

Tamper-Resistant Technique for Cryptographic Modules
NOZAKI Hanae / FUJISAKI Koichi / KAWAMURA Shinichi
Cryptographic modules are required to resist illegal reading of internal secret information or tampering with cryptographic functions. A tamper-resistant technique against implementation attacks, which have recently become a real threat posed by revealing the secret keys in cryptographic modules, has become increasingly important.
Toshiba has been developing and improving tamper-resistant techniques for both countermeasures and security evaluation in implementation of cryptographic modules for financial cards, e-passports, and so on. We are also aiming to contribute to the establishment of global security standards.

Trusted Computing for Software System Protection
ISOZAKI Hiroshi
A system that contains privacy-related data or confidential corporate data is required to behave in accordance with the intention of the system designers. In recent years, the concept of trusted computing has been attracting considerable interest as a solution for this. Trusted computing provides a computing platform with robust hardware to ensure that software behavior is not compromised.
Toshiba believes that this concept will be introduced to personal computers and consumer electronics devices in the near future. We are aiming at further enhancing security for digital devices by using security chips or storage devices standardized by the Trusted Computing Group (TCG).

Authentication Context for Biometrics (ACBio) to Secure Biometric Authentication in Open Networks
YAMADA Asahiko / OKADA Koji / IKEDA Tatsuro
Biometric authentication using body and behavioral features such as fingerprints and vein patterns, which has recently been introduced for automatic teller machines of banks, is expected to be applied to remote user authentication for online services such as Internet banking services in the near future. However, there are several problems related to user privacy, security and convenience, and cost of the service.
To solve these problems, Toshiba Solutions Corporation has developed the Authentication Context for Biometrics (ACBio), a technology for secure remote biometric authentication in open networks such as the Internet, which was standardized as an International Standard. With ACBio, more secure and convenient biometric authentication is realized.

Total Area Security Solution Using Noncontact-Type IC Cards and RFID Tags
SATO Mitsuhiko / WATANABE Hiromi / SHIMADA Hirokazu
A physical security system appropriately manages a physical space, such as access control by electric locks and gates to manage the movements of people through entrances and exits. However, it is often difficult to know the location as well as the exact numbers of all people entering and leaving facilities and buildings.
To strengthen the security and safety of buildings and facilities, Toshiba Solutions Corporation has developed a total area security solution that not only realizes control according to the security level of each area but also the collection and management of information about all of the people entering and leaving, using noncontact type IC cards and radio-frequency identification (RFID) tags. This system can contribute to improved safety in the event of a disaster with its function of collecting and managing information such as the locations and movements of people. In addition, it can also achieve seamless security in conjunction with logging on to a terminal and the use of surveillance cameras.


  Feature Articles

Low-Power-Loss Inverter with SiC Hybrid Pairs
TAKAO Kazuto / SHINOHE Takashi
Silicon carbide (SiC) power devices are a focus of high expectations as next-generation power devices offering low power loss, high-speed switching, and high-temperature operation compared with conventional silicon (Si) power devices.
Toshiba has demonstrated a reduction of more than 30% in inverter system power loss by the use of SiC hybrid pairs, which comprise originally developed 1,200 V-class SiC junction barrier controlled Schottky (SiC-JBS) diodes and Si insulated gate bipolar transistors (Si-IGBTs). SiC hybrid pairs make it possible to reduce both the power loss and volume of power converter systems.

Nanocontact Magnetoresistance Film with Current-Perpendicular-to-Plane Spin-Valve Structure for Ultrahigh-Density Magnetic Recording
FUKE Hiromi / HASHIMOTO Susumu / IWASAKI Hitoshi
A magnetic read head with high sensitivity at a low resistance-area (RA) product beyond that of current tunnel magnetoresistance (TMR) read heads is necessary in order to realize high-area-density recording of 2 Tbit/in2.
In response to this situation, Toshiba has developed a ferromagnetic nanocontact MR read element that is based on a new principle of MR effect and is expected to exhibit an MR ratio of more than 100% comparable to TMR read heads highly-pure. We have successfully achieved a nanocontact MR ratio of 20% for a current-perpendicular-to-plane (CPP) spin-valve structure with ferromagnetic nanocontacts.

Rapid Analysis of Brominated Flame Retardants Utilizing Ion Attachment Mass Spectrometry
OKI Mitsuhiro / KONDO Asato / HATAE Kumi
In the upstream processes of product manufacture including the material design and procurement phases, technologies for the measurement of environmental toxins have become increasingly important due to the enactment of environmental regulations such as the Restriction of Hazardous Substances (RoHS) Directive of the European Union. However, it is unrealistic to measure all of the parts and materials of electrical and electronic products due to the time and cost involved. Efforts are therefore being made to realize efficient and reliable technologies for the management of hazardous substances, including measuring technologies.
Toshiba has developed a new quantitative analysis method for brominated flame retardants (BFRs) in electrical and electronic products that utilizes ion attachment mass spectrometry (IAMS), which is a very soft ionization method that requires no separation technique before analysis. This method makes it possible to directly measure the elements in solid organic compounds within a short time.

2.5-inch, 500 GB Hard Disk Drive with High Rotation Speed of 7,200 rpm
OKAMURA Hiroshi / Josh Lindsay / Thorsten Schmidt
With notebook PCs being used for many purposes recently, hard disk drives (HDDs) have to meet the requirements of various applications. In particular, HDDs with a large memory capacity are required for the editing of audiovisual data by high-performance notebook PCs.
Toshiba has developed a 2.5-inch HDD with a capacity of 500 GB and a rotational speed of 7,200 rpm. To meet these specifications, we developed advanced features including a turbulence reducing device, a disk balancer, high stiffness and light suspension, a quiet top cover, a repeatable runout (RRO) compensation function, and iterative error-correcting code (ECC). In addition, a free-fall sensor (FFS) was applied to improve operational shock durability.

Digital Simultaneous Transmission System for Regional Disaster Prevention with Flexibility to Handle Various Applications
HIGASHIHARA Nobuyuki / AIZAWA Motoya
Municipalities operate public wireless systems based on their regional disaster prevention plan in order to provide residents with information on disasters and administrative matters, including simultaneous transmission systems to protect lives and property at a time of disaster. However, the changeover from analog to digital systems, in which a radio frequency is divided into multiple channels, has been delayed, and there are cases of equipment incompatibility due to the merging of municipalities.
With this as a background, Toshiba has developed a digital simultaneous transmission system that can be flexibly integrated step by step, and handles various applications including character transmission, data transmission, and image transmission.

LF650 Electromagnetic Flowmeter Detector Fulfilling Global Market Requirements
IIJIMA Takuya
Electromagnetic flowmeters are a type of industrial instrument that can measure the volumetric flow rate of conductive fluids such as water, sewage, chemicals, and so on. There is growing demand in overseas markets for electromagnetic flowmeters that provide high performance in low-temperature environments, applicability to a wide variety of fluids, and robustness against the installation environment.
To meet these requirements, Toshiba has developed the LF650 flange-type electromagnetic flowmeter detector. The LF650 can successfully operate in temperatures of -40°C or below in northern Europe and Canada due to the adoption of appropriate structural design and welding techniques to prevent the brittle destruction of steel. In addition, fluorine resin, an electrical insulating material, has been applied to the inside wall of the measurement pipe, making it possible to measure various types of fluids, including those at high temperature or with high erosion, high adhesion, or low conductivity, even under negative pressure.


  Frontiers of  Research & Development

Discrete Track Recording Technology for Large-Capacity Hard Disk Drives
Neutron Color I.I.TM Spawning New Applications for Inspection Technologies