Car sharing facilitates car owners and renters to share and use their cars conveniently. The popular car-sharing systems like Car2Go or Zipcar provide such facilities; however, they work line an intermediary or broker and thus pose various security and privacy threats. This paper proposes an alternate car-sharing model by constructing a decentralized cab consortium where the car owners and the renters can directly interact and share the car based on certain predefined agreements. We utilize the concept of smart contracts on top of a blockchain platform to realize such a system that provides a secured, tampered-proof, fair, and transparent interface for car sharing. We have implemented the proposed platform over an Ethereum-based environment and show that its runtime cost and performance are within a considerable margin.
{"title":"Beyond Uber and Lyft: A Decentralized Cab Consortium over Blockchains","authors":"S. Tripathy, Mayank Aggarwal, Sandip Chakraborty","doi":"10.1145/3457337.3457847","DOIUrl":"https://doi.org/10.1145/3457337.3457847","url":null,"abstract":"Car sharing facilitates car owners and renters to share and use their cars conveniently. The popular car-sharing systems like Car2Go or Zipcar provide such facilities; however, they work line an intermediary or broker and thus pose various security and privacy threats. This paper proposes an alternate car-sharing model by constructing a decentralized cab consortium where the car owners and the renters can directly interact and share the car based on certain predefined agreements. We utilize the concept of smart contracts on top of a blockchain platform to realize such a system that provides a secured, tampered-proof, fair, and transparent interface for car sharing. We have implemented the proposed platform over an Ethereum-based environment and show that its runtime cost and performance are within a considerable margin.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133673431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Feilong Wang, Yipeng Ji, Mingsheng Liu, Yangyang Li, Xiong Li, Xu Zhang, Xiaojun Shi
At present, the transaction delay of the consortium block chain applying the Practical Byzantine Fault Tolerance (PBFT) consensus protocol can only reach 2 to 5 seconds, and the throughput cannot reach tens of thousands. In addition as the number of nodes increases, the performance of the consortium block chain declines very quickly. The main challenge of previous research are to realize communication network topology of PBFT algorithm and high information exchange in the case of Byzantine failure, thus, this paper proposes an optimized Byzantine fault-tolerant algorithm to solve the performance bottleneck of the consortium chain. First of all, for the communication network structure of the whole network broadcast, we have reached an agreement on the transaction according to the pre-prepare and prepare phases of PBFT, and generally enter the commit phase, there is a high probability that the leader is honest, so we will communicate with the commit phase The network is optimized as a star communication structure. Second, combined with Tendermint, merge the view-change process of Byzantine failures of the normal consensus process, and switch the leader according to the longest chain principle. The algorithm is based on a partially synchronized network model to ensure the security and liveness of the protocol, and improve the performance and effective robustness.
{"title":"An Optimization Strategy for PBFT Consensus Mechanism Based On Consortium Blockchain","authors":"Feilong Wang, Yipeng Ji, Mingsheng Liu, Yangyang Li, Xiong Li, Xu Zhang, Xiaojun Shi","doi":"10.1145/3457337.3457843","DOIUrl":"https://doi.org/10.1145/3457337.3457843","url":null,"abstract":"At present, the transaction delay of the consortium block chain applying the Practical Byzantine Fault Tolerance (PBFT) consensus protocol can only reach 2 to 5 seconds, and the throughput cannot reach tens of thousands. In addition as the number of nodes increases, the performance of the consortium block chain declines very quickly. The main challenge of previous research are to realize communication network topology of PBFT algorithm and high information exchange in the case of Byzantine failure, thus, this paper proposes an optimized Byzantine fault-tolerant algorithm to solve the performance bottleneck of the consortium chain. First of all, for the communication network structure of the whole network broadcast, we have reached an agreement on the transaction according to the pre-prepare and prepare phases of PBFT, and generally enter the commit phase, there is a high probability that the leader is honest, so we will communicate with the commit phase The network is optimized as a star communication structure. Second, combined with Tendermint, merge the view-change process of Byzantine failures of the normal consensus process, and switch the leader according to the longest chain principle. The algorithm is based on a partially synchronized network model to ensure the security and liveness of the protocol, and improve the performance and effective robustness.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129516143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bitcoin remains the most widely used cryptocurrency. It has attracted users from tech enthusiasts to commercial investors to criminals, in no small part due to its reputation for anonymity. While not designed primarily for privacy, Bitcoin's architecture contains several provisions that can be exploited by criminals to conduct illegal activity including money laundering and collecting payments from ransomware and scams. Since Bitcoin's creation in 2008, various groups such as law enforcement, lawyers, criminals and privacy-focused Bitcoin users have been locked in a struggle between attempts to reveal hidden Bitcoin users' identities and attempts to keep those identities concealed. We present a survey of the techniques used within Bitcoin to reveal or conceal users' identities. We provide an easy to understand explanations of how these techniques work and provide a cross reference of which revealing techniques are effective for specific concealing techniques.
{"title":"Revealing and Concealing Bitcoin Identities: A Survey of Techniques","authors":"Karolin Bergman, S. Rajput","doi":"10.1145/3457337.3457838","DOIUrl":"https://doi.org/10.1145/3457337.3457838","url":null,"abstract":"Bitcoin remains the most widely used cryptocurrency. It has attracted users from tech enthusiasts to commercial investors to criminals, in no small part due to its reputation for anonymity. While not designed primarily for privacy, Bitcoin's architecture contains several provisions that can be exploited by criminals to conduct illegal activity including money laundering and collecting payments from ransomware and scams. Since Bitcoin's creation in 2008, various groups such as law enforcement, lawyers, criminals and privacy-focused Bitcoin users have been locked in a struggle between attempts to reveal hidden Bitcoin users' identities and attempts to keep those identities concealed. We present a survey of the techniques used within Bitcoin to reveal or conceal users' identities. We provide an easy to understand explanations of how these techniques work and provide a cross reference of which revealing techniques are effective for specific concealing techniques.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132911607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Scalable distributed control of large-scale computer systems is a challenge. Besides the control, reliability, fault-tolerance, and robustness are also fundamental considerations in designing and executing such systems. Blockchains have emerged as a splendid candidate to achieve such design considerations. More recent and perhaps more known examples of blockchain are in the financial sectors. However, blockchains have been in operation as distributed ledgers in supply chain for a long time. In this talk, we will revisit some of the foundational concepts related to blockchain technologies, draw parallels to systems research with a particular focus on reliability and security. By doing so we will unearth knowledgebase that can be deemed fruitful to resolve some of the pressing and outstanding challenges within systems and (cyber) infrastructures.
{"title":"Blockchains, Security, and Infrastructures: What we Know and What we Can Know","authors":"S. Khan","doi":"10.1145/3457337.3457849","DOIUrl":"https://doi.org/10.1145/3457337.3457849","url":null,"abstract":"Scalable distributed control of large-scale computer systems is a challenge. Besides the control, reliability, fault-tolerance, and robustness are also fundamental considerations in designing and executing such systems. Blockchains have emerged as a splendid candidate to achieve such design considerations. More recent and perhaps more known examples of blockchain are in the financial sectors. However, blockchains have been in operation as distributed ledgers in supply chain for a long time. In this talk, we will revisit some of the foundational concepts related to blockchain technologies, draw parallels to systems research with a particular focus on reliability and security. By doing so we will unearth knowledgebase that can be deemed fruitful to resolve some of the pressing and outstanding challenges within systems and (cyber) infrastructures.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114366242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Session details: BSCI Keynote","authors":"K. Choo","doi":"10.1145/3467994","DOIUrl":"https://doi.org/10.1145/3467994","url":null,"abstract":"","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128232254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Session details: BSCI Short Paper Session 1","authors":"Jong-Hyouk Lee","doi":"10.1145/3467997","DOIUrl":"https://doi.org/10.1145/3467997","url":null,"abstract":"","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121290001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Session details: BSCI Session 2","authors":"D. Peraković","doi":"10.1145/3467996","DOIUrl":"https://doi.org/10.1145/3467996","url":null,"abstract":"","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123187117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a safe, convenient and Blockchain-based way to sign Privately Offered Fund (POF) contracts. Our contributions are as follows: First, in order to reduce the CO2 emission from printing, delivery and mostly for the sake of security, we set up an electronic procedure for signing POF contracts. Second, we design and implement FutureText prototype using Hyperchain, which helps to share privacy information among stakeholders while keeping forged signature, counterfeited seal and twin-contracts away. Finally, to follow the legitimacy and compliance, we put forward methods for both authentication and signature of tripartite contracts. Besides, we put encrypted contracts on Blockchain while keeping original contracts on local database using heterogeneous storage, and that helps alleviate the prototype's storage pressure.
{"title":"FutureText: A Blockchain-based Contract Signing Prototype with Security and Convenience","authors":"Qing Zhang, Jianqun Gao, Qiqiang Qin, Chenyu Wang, Keting Yin","doi":"10.1145/3457337.3457844","DOIUrl":"https://doi.org/10.1145/3457337.3457844","url":null,"abstract":"This paper proposes a safe, convenient and Blockchain-based way to sign Privately Offered Fund (POF) contracts. Our contributions are as follows: First, in order to reduce the CO2 emission from printing, delivery and mostly for the sake of security, we set up an electronic procedure for signing POF contracts. Second, we design and implement FutureText prototype using Hyperchain, which helps to share privacy information among stakeholders while keeping forged signature, counterfeited seal and twin-contracts away. Finally, to follow the legitimacy and compliance, we put forward methods for both authentication and signature of tripartite contracts. Besides, we put encrypted contracts on Blockchain while keeping original contracts on local database using heterogeneous storage, and that helps alleviate the prototype's storage pressure.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115794876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a new approach and tool for blockchain software developers and architects to use for determining which computations of a smart contract can be effectively done off-chain without loss of trust and how they can be moved off-chain automatically. Our approach uses Finite State Machines (FSMs) and Hierarchical State Machines (HSMs) modeling in order to create smart contract patterns using graphs and then use pattern properties to identify which parts of the smart contracts should be considered for moving off-chain. Once software execution transits into the pattern's entry state, off-chain execution continues until the execution transits into the pattern's exit state, when execution continues on-chain. This paper further describes a tool for (1) FSM input and visualization, its analysis, and automatic transformation into a smart contract, and (2) an interface to support the developers' decision to optimally off-chain computations and to (3) define the communications between on-chain and off-chain computations.
{"title":"A Tool for Moving Blockchain Computations Off-Chain","authors":"Christian G. Liu, P. Bodorik, D. Jutla","doi":"10.1145/3457337.3457848","DOIUrl":"https://doi.org/10.1145/3457337.3457848","url":null,"abstract":"This paper proposes a new approach and tool for blockchain software developers and architects to use for determining which computations of a smart contract can be effectively done off-chain without loss of trust and how they can be moved off-chain automatically. Our approach uses Finite State Machines (FSMs) and Hierarchical State Machines (HSMs) modeling in order to create smart contract patterns using graphs and then use pattern properties to identify which parts of the smart contracts should be considered for moving off-chain. Once software execution transits into the pattern's entry state, off-chain execution continues until the execution transits into the pattern's exit state, when execution continues on-chain. This paper further describes a tool for (1) FSM input and visualization, its analysis, and automatic transformation into a smart contract, and (2) an interface to support the developers' decision to optimally off-chain computations and to (3) define the communications between on-chain and off-chain computations.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125541481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Smart contracts are self-executing programs running in the blockchain allowing for decentralised storage and execution without a middleman. On-chain execution is expensive, with miners charging fees for distributed execution according to a cost model defined in the protocol. In particular, transactions have a high fixed cost. In this paper we present MultiCall, an interpreter that reduces the cost of smart contract execution by emulating sequences of transactions from multiple users in one transaction. We have implemented and integrated MultiCall into Ethereum. Our evaluation shows that using MultiCall provides a saving between 56.8% and 98.9% of the fixed per-transaction cost compared to the standard approach of sending transactions individually.
{"title":"MultiCall: A Transaction-batching Interpreter for Ethereum","authors":"William Hughes, Alejandro Russo, G. Schneider","doi":"10.1145/3457337.3457839","DOIUrl":"https://doi.org/10.1145/3457337.3457839","url":null,"abstract":"Smart contracts are self-executing programs running in the blockchain allowing for decentralised storage and execution without a middleman. On-chain execution is expensive, with miners charging fees for distributed execution according to a cost model defined in the protocol. In particular, transactions have a high fixed cost. In this paper we present MultiCall, an interpreter that reduces the cost of smart contract execution by emulating sequences of transactions from multiple users in one transaction. We have implemented and integrated MultiCall into Ethereum. Our evaluation shows that using MultiCall provides a saving between 56.8% and 98.9% of the fixed per-transaction cost compared to the standard approach of sending transactions individually.","PeriodicalId":270073,"journal":{"name":"Proceedings of the 3rd ACM International Symposium on Blockchain and Secure Critical Infrastructure","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134018044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：