The Research Of AP-PRE And SASD Schemes Without Bilinear Pairing

In recent years,bilinear pairing technique has been widely used in many fields of cryptography,and many encryption and signature schemes based on bilinear pairing operations have been proposed.Pairing operation is considered to be one of the most costly cryptographic primitives with respect to computational complexity and memory cost.Even with the advanced implementation techniques,pairing operation takes twice the time taken by modular exponentiation computation.It is not suitable for proxy re-encryption,data aggregation and other scenarios where many users have limited computing resources.Therefore,in order to save computational overhead,it makes sense to construct lightweight cryptographic schemes that do not depend on pairing.The main work of this paper is as follows:· The proposal of a PADP scheme without pairing We propose an efficient privacypreseving data aggregation and authentication scheme without pairing for dynamic billing in smart grid.With threshold Paillier decryption,the scheme can prevent CS from colluding with malicious EVs less than threshold value,protecting the privacy of individual electricity consumption.Sequential Aggregate Signature Data based on Quadratic Residual is used to compress multiple users' signatures into a signature that is roughly the same size as a single signature.Aecurity analysis and simulation results show that the scheme can effectively prevent impersonation attack and greatly reduce the communication cost.· The proposal of an AP-PRE scheme without pairing With the notion of autonomous path proxy re-encryption(AP-PRE),we propose the first construction of an efficient AP-PRE scheme without pairing.Extensive evaluations demonstrate the effectiveness of our proposed AP-PRE.In particular,we present its application in off-chain payments in blockchain to ensure the atomicity of the hash time lock contract in the lightning network.We prove our construction of AP-PRE scheme is chosen ciphertext secure under the Modified Computational Diffie Hellman(MCDH)assumption in the random oracle model.Extensive performance comparisons demonstrate the efficiency in terms of both computational and communication overhead is dramatically optimized in the scheme.