Research On E-Commerce Protocol And Algorithms For Privacy Protection Based On Blockchain

With the rapid development of e-commerce,e-commerce system is facing many security probems,such as user privacy information disclosure,system centralization,unsafe and opaque logiatics process and so on.The emerging blockchain technology has been widely adopted in ecommerce transaction system to allow mutually distrustful parties for payment without trusted parties and protect user’s privacy information.However,most of the existing blockchain-based ecommerce transaction schemes could only deal with payment transaction,and they still had the problem of balance leakage.At the same time,the current blockchain-based e-commerce scheme also had the problems of privay leakage,system centralization,unsafe and opaque logiatics process,which made it difficult for blockchain-based e-commerce system to be safely and effectively applied in reality.In order to ensure the confidentiality requirements of user identity information in e-commerce system,realize the security and reliability of transaction payment process and the security of multi business transactions,ensure the security of logistics process and increase the transparency of logistics process,this thesis mainly studies e-commerce payment transaction scheme,multi business transcitons scheme and logistics scheme based on blockchain architecture.The main contributions of this thesis are as follows.Fistrly,in this thesis,we analyze an organization-friendly blockchain system,point out that the payment system is vulnerable to forery attack and collusion attack,which make attacker can illegally obtain the transaction amount,and give our countermeasures to remedy the forgery attack and collusion.We briefly introduces the organization-friendly blockchain system.Then,we analyze the security of the payment system,and give detailed process of forgery attack and coullison attack.Finally,we improve the transaction account address structure of the payment system,construct a new miner verification algorithm,and realize the function of preventing forgery attack and collusion attack.Secondly,in this thesis,we propose a blockchain-based anonymous e-commerce scheme with whole business transactions(BAES-WT),BAES-WT scheme can realize whole business secure transaction including goods release,goods purchase,payment transaction and goods delvery.Our BAES-WT scheme can achieve whole business secure transactions.We adopt pseudonym account address to achieve the anonymity for node,and apply elliptic curves digital signature algorithm(ECDSA)to achieve the unforgeability for whole business transactions.Our BAES-WT scheme can hide the account balance for all nodes.We design account model for node,and adopt Pedersen commitment algorithm and Bulletproof algorithm to hide account balance.Our BAES-WT scheme can achieve secure logistic process.We adopt elliptic curves cryptography(ECC)to encrypt the container address,and design an encrypted pick-up code strategy for users.Only legitimate user can correctly decrypt pick-up code to open the container.And through safety anslysis and performance anylysis,it is shown that BAES-WT scheme is safer and more efficient than other shcemes.Finally,in this thesis,we propose a blockchain-based anonymous logistics scheme with secure sharing(BALS-SS),BALS-SS scheme can relize safe and traceable logistics.Our BALSSS scheme can realize the identity anonymity for sender and recipient.We adopt random nickname account address to realize identity anonymity.Our BALS-SS scheme can achieve secure sharing of logistics information.We adopt elliptic curves cryptography(ECC)to encrypt the sending address and receiving address without disclose the address information for sender and recipient,and utilize the tamper proof of data on blockchain and logistics route list(List)to realize secure sharing of logistics information.Our BALS-SS scheme can achieve the traceability of logiatics information.We adopt elliptic curves digital signature algorithm(ECDSA)to sign the logistics information twice,and the sender can trace the logistics inoramtion on blockchain.And through safety anslysis and performance anylysis,it is shown that BAES-WT scheme is safer and more efficient than other shcemes.