Decentralized finance(DeFi)is a general term for a series of financial products and services.It is based on blockchain technology and has attracted people’s attention because of its open,transparent,and intermediary ...Decentralized finance(DeFi)is a general term for a series of financial products and services.It is based on blockchain technology and has attracted people’s attention because of its open,transparent,and intermediary free.Among them,the DeFi ecosystem based on Ethereum-based blockchains attracts the most attention.However,the current decentralized financial system built on the Ethereum architecture has been exposed to many smart contract vulnerabilities during the last few years.Herein,we believe it is time to improve the understanding of the prevailing Ethereum-based DeFi ecosystem security issues.To that end,we investigate the Ethereum-based DeFi security issues:1)inherited from the real-world financial system,which can be solved by macro-control;2)induced by the problems of blockchain architecture,which require a better blockchain platform;3)caused by DeFi invented applications,which should be focused on during the project development.Based on that,we further discuss the current solutions and potential directions ofDeFi security.According to our research,we could provide a comprehensive vision to the research community for the improvement of Ethereum-basedDeFi ecosystem security.展开更多
<div style="text-align:justify;"> <span style="font-family:Verdana;">We present Value Token Transfer Protocol (VTTP), a decentralized finance protocol for exchange of value or tokens wi...<div style="text-align:justify;"> <span style="font-family:Verdana;">We present Value Token Transfer Protocol (VTTP), a decentralized finance protocol for exchange of value or tokens within and between participating blockchain networks, fiat bank accounts and fiat wallets. The protocol allows intra-chain or inter-chain transfers of cryptocurrencies or tokens. VTTP works in both client-server and peer-to-peer models. The protocol comprises receiving from a client a transfer request to transfer value in a form of a cryptocurrency or a token, determining if the transfer request is intra-chain or inter-chain, transmitting to the client a response to the transfer request, the response comprising a raw transaction, receiving from the client a response to the raw transaction wherein a private key of a user is used to sign the raw transaction, defining a signed transaction, verifying a signature of the signed transaction and broadcasting the signed transaction to the sending and receiving blockchain networks.</span> </div>展开更多
Recent advancements in decentralized finance(DeFi)have resulted in a rapid increase in the use of Automated Market Makers(AMMs)for creating decentralized exchanges(DEXs).In this paper,we organize these developments by...Recent advancements in decentralized finance(DeFi)have resulted in a rapid increase in the use of Automated Market Makers(AMMs)for creating decentralized exchanges(DEXs).In this paper,we organize these developments by treating an AMM as a neoclassical black-box characterized by the conversion of inputs(tokens)to outputs(prices).The conversion is governed by the technology of the AMM summarized by an‘exchange function’.Various types of AMMs are examined,including:Constant Product Market Makers;Constant Mean Market Makers;Constant Sum Market Makers;Hybrid Function Market Makers;and,Dynamic Automated Market Makers.The paper also looks at the impact of introducing concentrated liquidity in an AMM.Overall,the framework presented here provides an intuitive geometric representation of how an AMM operates,and a clear delineation of the similarities and differences across the various types of AMMs.展开更多
基金supported by the Key-Area Research and Development Program of Guangdong Province 2020B0101090003CCF-NSFOCUS Kunpeng Scientific Research Fund (CCFNSFOCUS 2021010)+4 种基金Innovation Fund Program of the Engineering Research Center for Integration and Application of Digital Learning Technology of Ministry of Education under Grant No.1221027National Natural Science Foundation of China (Grant Nos.61902083,62172115,61976064)Guangdong Higher Education Innovation Group 2020KCXTD007 and Guangzhou Higher Education Innovation Group (No.202032854)Guangzhou Fundamental Research Plan of“Municipal-School”Jointly Funded Projects (No.202102010445)Guangdong Province Science and Technology Planning Project (No.2020A1414010370).
文摘Decentralized finance(DeFi)is a general term for a series of financial products and services.It is based on blockchain technology and has attracted people’s attention because of its open,transparent,and intermediary free.Among them,the DeFi ecosystem based on Ethereum-based blockchains attracts the most attention.However,the current decentralized financial system built on the Ethereum architecture has been exposed to many smart contract vulnerabilities during the last few years.Herein,we believe it is time to improve the understanding of the prevailing Ethereum-based DeFi ecosystem security issues.To that end,we investigate the Ethereum-based DeFi security issues:1)inherited from the real-world financial system,which can be solved by macro-control;2)induced by the problems of blockchain architecture,which require a better blockchain platform;3)caused by DeFi invented applications,which should be focused on during the project development.Based on that,we further discuss the current solutions and potential directions ofDeFi security.According to our research,we could provide a comprehensive vision to the research community for the improvement of Ethereum-basedDeFi ecosystem security.
文摘<div style="text-align:justify;"> <span style="font-family:Verdana;">We present Value Token Transfer Protocol (VTTP), a decentralized finance protocol for exchange of value or tokens within and between participating blockchain networks, fiat bank accounts and fiat wallets. The protocol allows intra-chain or inter-chain transfers of cryptocurrencies or tokens. VTTP works in both client-server and peer-to-peer models. The protocol comprises receiving from a client a transfer request to transfer value in a form of a cryptocurrency or a token, determining if the transfer request is intra-chain or inter-chain, transmitting to the client a response to the transfer request, the response comprising a raw transaction, receiving from the client a response to the raw transaction wherein a private key of a user is used to sign the raw transaction, defining a signed transaction, verifying a signature of the signed transaction and broadcasting the signed transaction to the sending and receiving blockchain networks.</span> </div>
文摘Recent advancements in decentralized finance(DeFi)have resulted in a rapid increase in the use of Automated Market Makers(AMMs)for creating decentralized exchanges(DEXs).In this paper,we organize these developments by treating an AMM as a neoclassical black-box characterized by the conversion of inputs(tokens)to outputs(prices).The conversion is governed by the technology of the AMM summarized by an‘exchange function’.Various types of AMMs are examined,including:Constant Product Market Makers;Constant Mean Market Makers;Constant Sum Market Makers;Hybrid Function Market Makers;and,Dynamic Automated Market Makers.The paper also looks at the impact of introducing concentrated liquidity in an AMM.Overall,the framework presented here provides an intuitive geometric representation of how an AMM operates,and a clear delineation of the similarities and differences across the various types of AMMs.
