A novel time-stamped signature scheme based upon DLP

This paper presents a time-stamped signature scheme based upon discrete logarithm problem. The signature consists of authenticated timestamp provided by a trusted authority, known as Time-Stamping Service (TSS), which provides time-stamp without knowing the content of the document.. The signature is universally verifiable, i.e., anyone can verify the validity of the signature using system´s public parameters. The security of the proposed scheme is based upon two hard problems, namely, integer factorization and discrete logarithm problem in random oracle model. The security of the scheme is analysed and proved to be resistant against active attacks. The proposed scheme is found to have considerably low computational cost and communication overhead as compared to existing schemes. Signature verification cost is also low. This scheme can have huge applications to real world digital communications, such as, submission of patent, online lottery, electronic voting system and e-commerce.