时间：2013年11月26日(星期二)下午15:30
地点：仓山校区成功楼603教室
主讲：电子科技大学/澳大利亚卧龙岗大学 禹勇博士
主办：数学与计算机科学学院、福建省网络安全与密码技术重点实验室
专家简介：禹勇博士现为电子科技大学副教授、澳大利亚卧龙岗大学Vice Chancellor Research Fellow，研究方向包括数字签名、公钥加密和云存储安全。主持国家自然科学基金项目两项，教育部博士点基金项目一项，在重要的国际学术期刊和国际学术会议上发表了30篇学术论文。担任ProvSec 2012和ACISP 2014的会议论文出版主席，是20个国内外期刊和10多个国际会议的审稿人。
报告摘要：Proxy signature is a useful cryptographic primitive for delegating the signing powers and has been suggested for use in many real world applications. The existing proxy signature schemes from factorization assumption are either insecure or inefficient. In this talk, we introduce two novel, efficient and provably secure proxy signature scheme from factorization. The first scheme is a clever consecutive execution of improved Rabin-type digital signature. While the second construction makes use of a factorization based key-exposure free chameleon hash function in the delegation phase and the proxy signer needs only to find a collision to a chameleon hash value to generate a valid proxy signature. As a result, it is highly efficient in terms of the computation of a proxy signature. Comparisons demonstrate that the new schemes outperform the known ones in terms of security, computational efficiency and the length of the public key.