活动类别：密码学学术报告

报告题目：Leakage Deterring Authenticated Secret Sharing and Application to Secure Cloud Computing

报告时间：9:30-11:30

报告日期：2019-11-03，星期日

地点：长安校区 文津楼三段6层3605

主办单位：永利yl23411 网络安全研究团队

报告人：徐秋亮 山东大学软件学院教授、博士生导师

讲座内容简介

        Is your data well protected by the cloud and how can you confirm that? This is a common concern for cloud users nowadays. One well-known paradigm to obtain data privacy while still maintains that it is can be computed conveniently is by using secret sharing. In this way, the clients hares its data among several servers on which computation and communication occurs. Privacy is guaranteed as long as the number of corrupted servers is under the reconstruction threshold of secret sharing scheme. However, in a profit-driven world, a server may take free ride of others, i.e., it does not invest money to protect the share in a hope that other server will do, then data privacy is still maintained. If no server invests money to protect its share, once those servers are breached by outside attacker, servers aren’t likely to report in a fear of reputation loss and penalty. In the end, the client is totally unaware of the leakage incident.

In this paper, we initiate the study of leakage evident secret sharing (LESS). A LESS scheme preserve the functionality of normal secret sharing scheme, but with additional property that once the secret is leaked, the client will aware of the incident from some public evidence. We propose an instantiation of LESS with the leakage evident property by using a public block chain. In addition, our analysis shows that the servers will protect the share with high probability in a fear of money lose. Finally, we give a proof-of-concept implementation to show its feasibility.。

 讲座人简介

徐秋亮，山东大学软件学院教授。现任中国密码学会理事，中国电子学会区块链分会副主任委员，山东商用密码协会理事长，山东网络空间安全专委会主任委员，中国密码学会密码算法专委会、安全协议专委会委员，密码学会密码应用工作委员会委员。

长期从事密码学与信息安全的研究，在安全多方计算、群组密码等方面具有长期积累，现在的主要研究兴趣是安全多方计算基础理论及实用化、云环境下的数据安全及其隐私保护下的（联合）利用、区块链理论与实践等。