CAJ | 학술논문

随着社交网络、云存储等新事物的出现，属性基加密以其强灵活性、强高效性、强安全性等优点得到了广泛的应用，但是目前的属性基加密方案大都是选择性安全的，不能很好地满足现实的应用需求，所以如何构造全安全的属性基加密方案成为密码学界研究的热点。针对以上问题，首先利用对偶系统加密构造了一个高效的密钥策略属性基加密方案；然后结合Lew ko‐Waters最新提出的证明思想证明了方案在标准模型下的全安全性；最后经分析比较，该方案的公私钥和密文长度与选择性安全的GPSW方案相当，但是安全性更高。同Lew ko‐Okamoto方案相比，该方案的安全性与之相同，但是具有较短的公钥长度和密文长度，方案的效率更高；而且，与Lekw o‐Waters的密文策略的属性基加密方案相对应，该方案在全安全证明中应用了选择性安全模型中的证明方法，对进一步研究选择性安全模型与全安全模型之间的关系具有重要意义。
수착사교망락、운존저등신사물적출현，속성기가밀이기강령활성、강고효성、강안전성등우점득도료엄범적응용，단시목전적속성기가밀방안대도시선택성안전적，불능흔호지만족현실적응용수구，소이여하구조전안전적속성기가밀방안성위밀마학계연구적열점。침대이상문제，수선이용대우계통가밀구조료일개고효적밀약책략속성기가밀방안；연후결합Lew ko‐Waters최신제출적증명사상증명료방안재표준모형하적전안전성；최후경분석비교，해방안적공사약화밀문장도여선택성안전적GPSW방안상당，단시안전성경고。동Lew ko‐Okamoto방안상비，해방안적안전성여지상동，단시구유교단적공약장도화밀문장도，방안적효솔경고；이차，여Lekw o‐Waters적밀문책략적속성기가밀방안상대응，해방안재전안전증명중응용료선택성안전모형중적증명방법，대진일보연구선택성안전모형여전안전모형지간적관계구유중요의의。
With the invention of many new applications such as social network and cloud storage , attribute‐based encryption has been studied and applied widely because of its great flexibility ,high efficiency and high security .As the current existing attributed‐based encryption schemes are most selectively secure ,which can't meet the need of the reality well ,how to construct fully secure ABE has been the focus of cryptography .Aimed at the problems mentioned above ,an key‐policy ABE scheme is firstly constructed by using the dual encryption system in this paper ,then the scheme is proved to fully secure in the standard model with the new ideas proposed by Lewko and Waters . Finally the comparison results show that the public and private key lengths of our scheme are similar to the selectively secure GPSW scheme ,but our scheme is more secure .Compared with the Lewko‐Waters scheme ,our scheme has the same security ,but has shorter public and private key lengths , which is more efficient .What's more ,similar to the ciphertext‐policy scheme of Lekwo‐Waters ,the techniques of selective security are also utilized in the security proof of our key‐policy ABE ,w hich is important in the research of the relation between the selective and full security models .