| dc.description.abstract | In this thesis, we focus on the topic of signature schemes with the forward security. Firstly, a survey of some signature schemes which are devoted to solving the key exposure problem is presented. Secondly, the proposed schemes, forward-secure blind signature schemes are introduced.
There are some ways to solve the key exposure problem. We classify them into four parts. They are the forward security, the pairing-based forward security, the key-insulted security, and the intrusion-resilient security. In the class of the forward security, we put more attention on describing all the evolution, each important key idea, new scheme, and security analysis. At the same time, some well design charts are used to help the readers to catch the whole development. In the class of the pairing-based forward security, we put attention on the structure which are used to achieve the forward security rather than describe each scheme in detail. In the class of the key-insulated security and the intrusion-resilient security, we focus on their purposes and the de¯nitions. Finally, the relationships between the forward
security, the key-insulted security, and the intrusion-resilient security and forward-secure signature schemes with special properties are presented.
The Blind signature which provides the properties of anonymity and unforgeability is employed in many large scale social activities and ¯nancial applications. If signer’’s secret key is compromised, the signature signed before will not be believed again. So, this kind of system will suffer a great loss. Forward-secure property is a security notion to preserve that a compromised current secret key does not help an adversary to forge any signature in some past time period. Therefore, the blind signature with the forward security becomes evidently important and necessary. In this thesis, we present two forward-secure blind signature schemes, which are based on Fiat-Shamir and Ong-Schnorr blind signatures, respectively. We give the proofs of the two forward-secure blind signature schemes with the blindness and forward security. | en_US |