Best Paper Award 2015

Best Paper Award

Dual Pairing Vector Spaces and Their Applications

Tatsuaki OKAMOTO，Katsuyuki TAKASHIMA

[Trans. Fundamentals., Jan. 2015]

Tatsuaki OKAMOTO

Katsuyuki TAKASHIMA

  Highly functional encryption, such as attribute-based encryption and functional encryption, is a generalized and advanced notion of public-key encryption and has been extensively studied in the last decade as a key technology to enhance the security and privacy of cloud computing and big data searches since it offers the functionality of computation and data search on encrypted data. The concept of dual pairing vector spaces (DPVS) was introduced by the authors of this paper in 2009 as a methodology to realize a range of functional encryption schemes in a practical and secure manner. This concept constructs dual vector spaces based on bilinear groups, and generalized and systematized existing techniques such as the vector-like usages by the direct-product of groups and by composite-order bilinear groups. This also led to the development of a new information theoretical methodology for security proofs. As a result, the concept has been widely applied to various forms of research such as the construction of practical and secure inner-product encryption, attribute-based encryption, functional encryption, attribute-based signatures and watermarking.
  This paper, for the first time, presents the main techniques of DPVS and the most significant results obtained using the concept in a comprehensive and systematic way, and shows how to employ the various techniques developed by the authors for the construction and security proof of a variety of functional encryption schemes. For example, fully secure attribute-based encryption on prime-order bilinear groups and fully secure attribute-hiding inner-product encryption were achieved for the first time by utilizing DPVS. This paper presents, clearly and systematically, how the concept and techniques of DPVS were employed to obtain these research outcomes.
  To summarize, DPVS is a very powerful methodology that realizes highly functional encryption schemes securely and practically and is expected to advance and promote this area by developing the techniques described in this paper and applying them to wider topics. Due to the major contributions described above, this paper deserves this society’s paper award.