Design And Analysis Of Content Extraction Signatures Scheme Based On Identity

With the rapid development of computer network, information security becomes one of the key factors of network development. Digital signature technology is the core technology of cryptography, it provides data integrality, non-repudiation and identity authentication. It is widely used in electronic commerce and government affair etc, it is the basis and important guarantee of Information Security theory.Identity-based signature, as one of the research directions of Digital signature technology, has good qualities, so it caused the widespread attention of people the moment it was proposed. The biggest difference with normal Digital signature is that it uses the identity information of itself as public key, and is convenient and reliable. Identity-based signature is getting more and more widely used in Electronic bank and E-commerce.This article does some research on the problem of Identity-based signature, and obtained the following three achievements.1. by combining Identity-based signature scheme and Content Extraction Signature, a Content Extraction Signature of Identity-based signature scheme has been proposed. This scheme introduces two PKG, it can individually and randomly choose a random number to compute the partial private keys for the user, the real private keys of users are obtained by computing the two partial private keys. By doing this, it can eliminate a certain level of safeness trouble of one PKG’s forging user’s signature haphazardly.2. This paper proposed a Content Extraction Signatures Without Trusted Party Based On Identity. In this scheme, the user chooses a random number to save by itself, and uses this random number to compute the user’s public key, because this scheme is the difficult problem based on q-SDHP, so it can solve the problem of one PKG’s forging user’s signature better. We also prove that our ID-CES scheme is un-forgeability under the GDH assumption and ID attack. Compared to other Content Extraction Signatures, this scheme has higher efficiency.3. Combined content extraction signature and Identity based and key insulated cryptosystem,we proposed the Content Extraction Signatures Based on Identity and Key Insulated scheme. The new scheme satisfied the essential natures of Identity-based signature scheme, and it realized that forward signature is still effective, even if the signer’s secret key is leakd. It reduce the danger that secret key leak is brought in large extent. The scheme is proved that un-forgeability under the GDH assumption and ID attack.