TC: Small: Collaborative Research: Implications of Fully Homomorphic Encryption

最近，Gentry等人已经建立了构造全同态加密方案的可行性。简而言之，全同态加密（FHE）方案是允许具有多个消息的密文的第三方在不知道解密密钥的情况下构造与应用于原始消息的任意有效可计算函数相对应的新密文的方案。完全同态加密有可能允许不同的组织在其池化数据集上计算基本功能，而不会相互泄露这些数据。因此，这是实现“需要知道”隐私的最终解决方案。在Gentry的发现之前，很少有研究人员相信FHE可以被构建。因此，这个概念没有得到很好的研究，尽管它显然有潜力以保护隐私的方式解决重要任务。特别是，FHE和传统公钥密码学之间的基本关系仍然不清楚。这个研究项目的目标是正式这种关系，建立FHE的概念，满足更强的安全保证，如安全，即使当对手有机会获得一个受限制的解密预言，并有可能使用这些更强的安全保证应用FHE在安全和隐私保护计算。为了确保研究产生更广泛的影响，该项目包括对从本科到博士后的各级学生进行辅导，以及对传统上代表性不足的学生和K-12学生进行外联活动。该项目的研究成果将通过在会议、期刊和互联网上的介绍和出版物传播。

Recently, Gentry and others have established the feasibility of constructing fully homomorphic encryption schemes. Briefly, a fully homomorphic encryption (FHE) scheme is one that allows a third-party who has ciphertexts of several messages to construct---without knowing the decryption key---a new ciphertext that corresponds to an arbitrary efficiently computable function applied to the original messages. Fully homomorphic encryption has the potential to allow disparate organizations to compute basic functions on their pooled data-sets without revealing such data to each other. It is thus an ultimate solution for implementing ``need-to-know'' privacy. Until Gentry's discovery, few researchers believed that FHE could be constructed. As a result, the concept has not been well-studied despite its clear potential to solve important tasks in a privacy-preserving manner. In particular, the basic relationship between FHE and traditional public-key cryptography remains unclear. The goals of this research project are to formalize this relationship, to build notions of FHE that satisfy stronger security guarantees such as security even when the adversary has access to a restricted decryption oracle, and to potentially use these stronger security guarantees to apply FHE in secure and privacy preserving computation. To ensure the broader impact of the research, this project includes mentoring of students at all levels from undergraduate to post-doctoral and outreach activities to traditionally under-represented students and K-12 students. Research from this project will be disseminated through presentations and publications in conferences, journals and on the Internet.