NTT Research, Inc., a division of NTT (TYO:9432), has announced that a paper co-authored in 2005 by Dr. Brent Waters, a distinguished scientist in its Cryptography and Information Security (CIS) Lab, has won an International Association for Cryptologic Research (IACR) Test-of-Time Award, the company said.
Dr. Waters and Dr. Amit Sahai, a professor of computer science at the UCLA Samueli School of Engineering, delivered their paper, “Fuzzy Identity-Based Encryption,” at the 2005 Eurocrypt conference. The paper introduced attribute-based encryption, in which policy rather than individuals determines who can encrypt.
The IACR gives Test-of-Time Awards annually to papers that were delivered 15 years prior at each of the three IACR General Conferences (Eurocrypt, Crypto and Asiacrypt) and that have had a lasting influence on the field.
In Identity-Based Encryption (IBE), which was initially proposed in the mid-1980s, a sender encrypts a message to an identity without access to a public key certificate. What Sahai and Waters proposed in their 2005 Eurocrypt paper was a new type of IBE in which identities were viewed as a set of descriptive attributes. They called this type of IBE “fuzzy” because the system allowed for a certain amount of error-tolerance in the identities.
In Fuzzy IBE, policy checking happens “inside the crypto,” as attributes of the secret key are mathematically incorporated within the key itself. In other words, nobody explicitly evaluates the policies and makes an access decision. Rather, if the policy is satisfied, decryption will simply work; otherwise, it won´t. The authors proved the security of their schemes under the Selective-ID security model.
NTT Research opened its Palo Alto offices in July 2019 as a new Silicon Valley startup to conduct basic research and advance technologies that promote positive change for humankind. Currently, three labs are housed at NTT Research: the Physics and Informatics (PHI) Lab, the Cryptography and Information Security (CIS) Lab, and the Medical and Health Informatics (MEI) Lab.