Provably Secure On-Line Secret Sharing Scheme

Tatsumi OBA  Wakaha OGATA  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E94-A   No.1   pp.139-149
Publication Date: 2011/01/01
Online ISSN: 1745-1337
DOI: 10.1587/transfun.E94.A.139
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Secure Protocol
secret sharing,  on-line secret sharing,  public bulletin board,  provably secure,  

Full Text: PDF(389.9KB)>>
Buy this Article

On-line secret sharing scheme, introduced by Cachin, is a computational variation of secret sharing scheme. It supports dynamic changing of access structures and reusable shares, by grace of public bulletin board. In this paper, first we introduce a formal model of on-line secret sharing scheme, and analyze existing on-line secret sharing schemes. As a result, it is shown that they are all vulnerable by giving concrete attacks. Next, we propose a novel on-line secret sharing scheme which is provably secure.