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Research & Development


High Performance Modular-squaring-based public-key Encryption (Revised Version)

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Highly-secure low-power public key cryptosystem developed by Hitachi. Pronounced "heim-are". Features of HIME(R) are as follows:

(1) Encryption method with provable security

HIME(R) has the highest security level defined by the security theory of the public key cryptosystem. For this reason, even under heavy attack, it would be difficult to extract even a part of the original data (plain text) from the encrypted data (cipher text). Further, through it standardization activities, HIME(R) has undergone many security evaluations and verifications, and the validity of the proof of security has been objectively guaranteed.

(2) High-speed encryption/decryption with low power consumption

Encryption with HIME(R) uses the OAEP method for message padding, followed by a single modular squaring. These operations are very concise and efficient.
Moreover, the form of the modulus (composite number) in modular multiplication was devised in order to attain high-speed processing of decryption.
Compared with an RSA cryptosystem(using OAEP) for the same key length, HIME(R) encryption processing is about ten times faster and decryption processing is about two to three times faster. High-speed performance is directly linked to curbing power consumption, and therefore is operable in ubiquitous or portable information terminals.

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