Efficient Certificate-based Signature And Its Aggregation

With the continuous development of computer network technology,digital information has become the main carrier in our daily lives.How to ensure the security and efficiency of the transmission of information in the network is still a hot topic in academia.As an important branch of cryptography,digital signature can provide authentication,integrity and non-repudiation functionality for information in network.Aggregate signature allows any to aggregate several signatures by multiple users into a single signature.Due to its aggregation functionality,aggregate signature can be used in many applications where bandwidth and storage are constrained.Certificate-based signature(CBS)is regarded as the most effective signature in terms of that it can simplify certificate management procedures in traditional public key infrastructure and eliminate the key escrow problem in ID-based public key cryptography simultaneously.Since its invention in 2004,it has received many attentions from academia,many certificate-based signature schemes have been proposed.However,the existing schemes have one of the following two disadvantages at least:1)only support partial aggregateability;2)require a pre-negotiated one-time-use nonce.To solve these problems,in this paper,we focus on the study of(CBS)and its aggregation.The main contributions are as follows:1.According to the definition and security model of CBS,we propose a new CBS scheme using bilinear pairing.The proposed CBS scheme has the following advantages:1)provable security:the proposal can be proved secure based on the CDH assumption;(2)high efficiency:the proposed CBS scheme does not need any pairing in the signing algorithm,and need only four pairings in the verification algorithm;(3)full aggregateability:every part in the signature can be aggregated.2.Based on the proposed CBS scheme,we propose a new certificate-based aggregate signature(CBAS)scheme.The proposed CBAS scheme has the following features inherited from the proposed CBS scheme:(1)full aggregateability;(2)no pre-negotiated one-time-use nonce;(3)efficient aggregation and verification algorithms.Finally,we prove our proposal in the random oracle model.3.We also implement the proposed CBS scheme and CBAS scheme by using cryptographic library.The experimental results also show that our proposals are efficient and effective.