講演抄録/キーワード |
講演名 |
2017-05-12 16:30
[招待講演]非線形な分割技法によるコンパクトなIDベース暗号の提案 ○勝又秀一(東大)・山田翔太(産総研) ISEC2017-11 |
抄録 |
(和) |
(まだ登録されていません) |
(英) |
In this paper, we present new adaptively secure identity-based encryption (IBE) schemes. One of the distinguishing properties of the schemes is that it achieves shorter public parameters than previous schemes. Both of our schemes follow the general framework presented in the recent IBE scheme of Yamada (Eurocrypt 2016), employed with novel techniques tailored to meet the underlying algebraic structure to overcome the difficulties arising in our specific setting. Specifically, we obtain the following:
- Our first scheme is proven secure under the ring learning with errors (RLWE) assumption and achieves the best asymptotic space efficiency among existing schemes from the same assumption.
The main technical contribution is in our new security proof that exploits the ring structure in a crucial way. Our technique allows us to greatly weaken the underlying hardness assumption (e.g., we assume the hardness of RLWE with a fixed polynomial approximation factor whereas Yamada's scheme requires a super-polynomial approximation factor) while improving the overall efficiency.
- Our second IBE scheme is constructed on bilinear maps and is secure under the $3$-computational bilinear Diffie-Hellman exponent assumption. This is the first IBE scheme based on the hardness of a computational/search problem, rather than a decisional problem such as DDH and DLIN on bilinear maps with sub-linear public parameter size. |
キーワード |
(和) |
/ / / / / / / |
(英) |
identity-based encryption / LWE / ideal lattice / bilinear map / / / / |
文献情報 |
信学技報, vol. 117, no. 25, ISEC2017-11, pp. 61-61, 2017年5月. |
資料番号 |
ISEC2017-11 |
発行日 |
2017-05-05 (ISEC) |
ISSN |
Print edition: ISSN 0913-5685 Online edition: ISSN 2432-6380 |
著作権に ついて |
技術研究報告に掲載された論文の著作権は電子情報通信学会に帰属します.(許諾番号:10GA0019/12GB0052/13GB0056/17GB0034/18GB0034) |
PDFダウンロード |
ISEC2017-11 |