CAJ | 학술논문

基于身份的加密是一种直接以用户的身份作为公钥的加密方案。自提出以来，利用双线性对实现基于身份的加密方案的案例已经有很多，但是这些方案大都是采用对称的双线性对，即要求作为映射输入的两个群相同。这无疑缩小了映射中所选取的椭圆曲线的范围，将在一种更一般的条件下，即在非对称双线性对下，基于判定性双线性Diffe-Hellman( BDHE)难解问题在标准模型下构造出一种新型的基于身份的加密方案，并证明其在标准模型下具有不可区分的选择身份的选择明文( IND-sID-CPA)安全性。
기우신빈적가밀시일충직접이용호적신빈작위공약적가밀방안。자제출이래，이용쌍선성대실현기우신빈적가밀방안적안례이경유흔다，단시저사방안대도시채용대칭적쌍선성대，즉요구작위영사수입적량개군상동。저무의축소료영사중소선취적타원곡선적범위，장재일충경일반적조건하，즉재비대칭쌍선성대하，기우판정성쌍선성Diffe-Hellman( BDHE)난해문제재표준모형하구조출일충신형적기우신빈적가밀방안，병증명기재표준모형하구유불가구분적선택신빈적선택명문( IND-sID-CPA)안전성。
Identity-based encryption is a method which directly uses the user's identity as its public key. Since it appears, there are a lot of identity-based encryption schemes from bilinear pairings, but most of these schemes uses symmetric bilinear pairings as their math tools, namely the groups as it put in the bilin-ear mapping should be the same one. This would greatly reduce the scope of the available elliptic curves in the encryption schemes. This paper proposes a new type of identity-based encryption scheme from the asymmetric bilinear pairings without using random oracles, in a more general bilinear pairings conditions, and proves that it has indistinguishable selective-ID CPA security by reducing it to decision-BDH problem under the standard model.