2009年11月13日-16日，实验室林昌露赴广州参加由中国密码学会主办、广州大学承办的“中国密码学会2009年会”。会议特邀国内外四位（张方国教授（中山大学）、Prof. Tor Helleseth（University  of Bergen, Norway）、李超教授（国防科技大学）、Prof. Josef Pieprzyk（Macquqire University, Australia））密码学专家作专题学术报告。此次会议内容涉及密码学各研究课题，包括：对称密码、公钥密码、密钥共享、数字签名、密码协议、密码实现与应用。信息隐藏于数字水印等。林昌露博士就被大会就录用的论文“Perfect (t, n) Threshold Secret Sharing  Scheme”在大会上做了宣读和交流。

      Shamir  proposed the first (t, n) threshold secret sharing scheme in which shares are  generated by a polynomial over finite field and the secret can be reconstructed  using Lagrange interpolation formula. Ghodosi et al. have shown that Shamir's  scheme is not perfect if the degree of the polynomial is exactly (t-1). They  also pointed out that Shamir's scheme is perfect if the degree of the  polynomial is at most (t-1). All shareholders can follow the verifiable secret  sharing (VSS) scheme proposed by Benaloh, without revealing the secret and the  corresponding shares, to verify that all shares are generated by a polynomial  with degree at most (t-1). Very recently, Lin et al. have come up a new  definition of strong verifiable secret sharing (SVSS). In SVSS, shares are  generated by a polynomial with degree exactly (t-1). In this paper, we propose  a new (t, n) threshold secret sharing scheme in which shares are generated by a  polynomial with degree exactly (t-1) and is perfect. Our proposed scheme is as  efficient as Shamir's scheme.