时 间：2013年7月25日（星期四）下午14:30
地 点：仓山校区成功楼603室
主 讲：新加坡南洋理工大学, 王华雄教授
主 办：数学与计算机科学学院
专家简介: Wang Huaxiong graduated from Fujian Normal University with a BSc in 1984 and a Master in 1989, both in Mathematics. He then received a PhD in Mathematics from University of Haifa, Israel in 1996 and a PhD in Computer Science from University of Wollongong, Australia in 2001. He joined Nanyang Technological University in 2006 and is currently an associate professor in the Division of Mathematical Sciences. Prior to that, he held positions in several universities, including Macquarie University, Australia; City University, Hong Kong; University of Wollongong, Australia; National University of Singapore; Kobe University, Japan; Fujian Normal University, China.
His research interests include cryptography, information security, coding theory, combinatorics and theoretical computer science. He was on the editorial boards of Designs, Codes and Cryptography (2006 -2011), and is currently on the editorial boards of International Journal of Foundations of Computer Science, Journal of Communications (JCM) and Journal of Communications and Networks. He was the Program Co-Chair of 9th Australasian Conference on Information Security and Privacy (ACISP'04), Sydney, Australia, 2004 and 4th International Conference on Cryptology and Network Security (CANS05), Xiamen, China, 2005. He received the inaugural Award of Best Research Contribution awarded by the Computer Science Association of Australasia in 2004.
题目 1: Private Information Retrieval and Locally Decodable Codes.
Abstract: Private Information Retrieval (PIR) is a cryptographic solution that allows a user to retrieve a data item of their choice from a database, such that the server storing the database does not gain any information on the identity of the item being retrieved. A trivial solution to the PIR problem is to send the entire database to the user. In this perfect privacy solution, the communication complexity is prohibitively large. For example, consider retrieval from a Web search-engine. One of the most significant goals of PIR-related research has been to minimize the communication overhead imposed by the privacy constraint. Since the PIR problem was first formulated by Chor, Goldreich, Kushilevitz and Sudan in 1995, it has been an area of active research and various settings and extensions have been considered.
A locally decodable code (LDC) is an error-correcting code that allows to decode a single bit of a message with high probability by only looking at a small number of bits of a possibly partially corrupted codeword.
In this talk, we will discuss how to construct PIR schemes from LDCs, and report some of the recent results.
题目2: Threshold Cryptography: Non-Homomorphic Cases
Abstract: In threshold cryptography the goal is to distribute the computation of basic cryptographic primitives across a number of nodes in order to relax trust assumptions on individual nodes, as well as to introduce a level of fault-tolerance against node compromise. Most threshold cryptography has previously looked at the distribution of public key primitives, particularly threshold signatures and threshold decryption mechanisms. In this talk we look at the application of threshold cryptography to symmetric primitives, and in particular the pseudo-random functions, the encryption or decryption of a symmetric key block cipher.