Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169431
Victor Ermolaev, Indrek Klangberg, Y. Madhwal, Silver Vapper, Sjoerd Wels, Y. Yanovich
In modern and interconnected world, information is accumulatively stored digitally, making the process of exchanging, gathering and querying the information much easier. Continuously, it has introduced new challenges about how to ensure its consistency and reliability due to the sheer volume of data. A blockchain-based information system can provide an incorruptible record of history, enabling better auditing and data management practices. The paper describes how to combine an Exonum blockchain and a Neo4j graph database into a system that can provide a verifiable audit trail of data integrity and its modifications for information stored in a graph database.
{"title":"Incorruptible Auditing: Blockchain-Powered Graph Database Management","authors":"Victor Ermolaev, Indrek Klangberg, Y. Madhwal, Silver Vapper, Sjoerd Wels, Y. Yanovich","doi":"10.1109/ICBC48266.2020.9169431","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169431","url":null,"abstract":"In modern and interconnected world, information is accumulatively stored digitally, making the process of exchanging, gathering and querying the information much easier. Continuously, it has introduced new challenges about how to ensure its consistency and reliability due to the sheer volume of data. A blockchain-based information system can provide an incorruptible record of history, enabling better auditing and data management practices. The paper describes how to combine an Exonum blockchain and a Neo4j graph database into a system that can provide a verifiable audit trail of data integrity and its modifications for information stored in a graph database.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126884517","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169416
Chenggang Wang, Boyang Wang, Xinxin Fan
One of the major challenges of cryptocurrendes is the lack of confidentiality, Without confidentiality, the amount of each transaction on a blockchain is not private. While confidential transactions can hide transaction amounts, its storage overhead is extremely high (e.g., 10~20X). This substantial overhead significantly raises users’ overheads in bootstrapping and impedes new nodes, especially for resource-limited devices.We devise a new method, referred to as EcoBoost, to advance the effidency of bootstrapping for blockchains supporting confidential transactions. Specifically, we harness random sampling to verify the correctness of confidential transactions with high probability. As a result, the verification overhead is sublinear with regard to the number of transactions (compared to linear in current solutions). Our experiment results show that, if Bitcoin implements confidential transactions, EcoBoost can save over 86% storage and verification time in bootstrapping but still detect bogus transactions with a probability of 99%.
{"title":"EcoBoost: Efficient Bootstrapping for Confidential Transactions","authors":"Chenggang Wang, Boyang Wang, Xinxin Fan","doi":"10.1109/ICBC48266.2020.9169416","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169416","url":null,"abstract":"One of the major challenges of cryptocurrendes is the lack of confidentiality, Without confidentiality, the amount of each transaction on a blockchain is not private. While confidential transactions can hide transaction amounts, its storage overhead is extremely high (e.g., 10~20X). This substantial overhead significantly raises users’ overheads in bootstrapping and impedes new nodes, especially for resource-limited devices.We devise a new method, referred to as EcoBoost, to advance the effidency of bootstrapping for blockchains supporting confidential transactions. Specifically, we harness random sampling to verify the correctness of confidential transactions with high probability. As a result, the verification overhead is sublinear with regard to the number of transactions (compared to linear in current solutions). Our experiment results show that, if Bitcoin implements confidential transactions, EcoBoost can save over 86% storage and verification time in bootstrapping but still detect bogus transactions with a probability of 99%.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131535737","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169391
H. Gersbach, A. Mamageishvili, Manvir Schneider
We initiate the study of vote delegation in a costly voting setting and compare its performance to conventional voting. Our central insight is that if the number of malicious voters is comparatively low, delegation dominates conventional voting. If the number of malicious voters is moderate, then conventional voting tends to be better than vote delegation. If the number of malicious voters is high, both voting methods fail to deliver a positive outcome.
{"title":"Vote Delegation and Malicious Parties","authors":"H. Gersbach, A. Mamageishvili, Manvir Schneider","doi":"10.1109/ICBC48266.2020.9169391","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169391","url":null,"abstract":"We initiate the study of vote delegation in a costly voting setting and compare its performance to conventional voting. Our central insight is that if the number of malicious voters is comparatively low, delegation dominates conventional voting. If the number of malicious voters is moderate, then conventional voting tends to be better than vote delegation. If the number of malicious voters is high, both voting methods fail to deliver a positive outcome.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133557300","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169446
Shiquan Zhang, Kaiwen Zhang, Bettina Kemme
Proof-of-Work (PoW) is the core of the most popular consensus protocol among current mainstream blockchain systems including Bitcoin. Selfish mining attacks are a possible threat towards PoW-based systems and recent works have shown that a miner can profit using selfish mining if it has more than 25% of the overall mining power. In this paper, we present a simulator based on a Markov Process model that can analyze scenarios where there are multiple, independently working selfish miners. In our evaluations, we present detailed results with two attackers showing that the threshold for profitable selfish mining decreases to 21% in this case.
{"title":"A Simulation-Based Analysis of Multiplayer Selfish Mining","authors":"Shiquan Zhang, Kaiwen Zhang, Bettina Kemme","doi":"10.1109/ICBC48266.2020.9169446","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169446","url":null,"abstract":"Proof-of-Work (PoW) is the core of the most popular consensus protocol among current mainstream blockchain systems including Bitcoin. Selfish mining attacks are a possible threat towards PoW-based systems and recent works have shown that a miner can profit using selfish mining if it has more than 25% of the overall mining power. In this paper, we present a simulator based on a Markov Process model that can analyze scenarios where there are multiple, independently working selfish miners. In our evaluations, we present detailed results with two attackers showing that the threshold for profitable selfish mining decreases to 21% in this case.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131034091","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169411
Markus Luecking, Christian Fries, Robin Lamberti, W. Stork
Today, Internet of Things (IoT) devices mostly operate in enclosed, proprietary environments. To unfold the full potential of IoT applications, a unifying and permissionless environment is crucial. All IoT devices, even unknown to each other, would be able to trade services and assets across various domains. In order to realize those applications, uniquely resolvable identities are essential. However, quantifiable trust in identities and their authentication are not trivially provided in such an environment due to the absence of a trusted authority. This research presents a new identity and trust framework for IoT devices, based on Distributed Ledger Technology (DLT). IoT devices assign identities to themselves, which are managed publicly and decentralized on the DLT’s network as Self Sovereign Identities (SSI). In addition to the Identity Management System (IdMS), the framework provides a Web of Trust (WoT) approach to enable automatic trust rating of arbitrary identities. For the framework we used the IOTA Tangle to access and store data, achieving high scalability and low computational overhead. To demonstrate the feasibility of our framework, we provide a proof-of-concept implementation and evaluate the set objectives for real world applicability as well as the vulnerability against common threats in IdMSs and WoTs.
{"title":"Decentralized Identity and Trust Management Framework for Internet of Things","authors":"Markus Luecking, Christian Fries, Robin Lamberti, W. Stork","doi":"10.1109/ICBC48266.2020.9169411","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169411","url":null,"abstract":"Today, Internet of Things (IoT) devices mostly operate in enclosed, proprietary environments. To unfold the full potential of IoT applications, a unifying and permissionless environment is crucial. All IoT devices, even unknown to each other, would be able to trade services and assets across various domains. In order to realize those applications, uniquely resolvable identities are essential. However, quantifiable trust in identities and their authentication are not trivially provided in such an environment due to the absence of a trusted authority. This research presents a new identity and trust framework for IoT devices, based on Distributed Ledger Technology (DLT). IoT devices assign identities to themselves, which are managed publicly and decentralized on the DLT’s network as Self Sovereign Identities (SSI). In addition to the Identity Management System (IdMS), the framework provides a Web of Trust (WoT) approach to enable automatic trust rating of arbitrary identities. For the framework we used the IOTA Tangle to access and store data, achieving high scalability and low computational overhead. To demonstrate the feasibility of our framework, we provide a proof-of-concept implementation and evaluate the set objectives for real world applicability as well as the vulnerability against common threats in IdMSs and WoTs.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129247584","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169467
Monika di Angelo, Gernot Slazer
On the blockchain, cryptocurrencies play a role similar to cash, while cryptographic tokens are a universal tool for handling rights and assets. Software wallets interact with blockchains in general and with smart contracts (on-chain programs) in particular. Some wallets are realized (partly) as smart contracts with the intent to increase trust and security by being transparent and by offering features like daily limits, approvals, multiple signatures, and recovery mechanisms.Ethereum is the most prominent platform for both, tokens and smart contracts, and thus also for wallet contracts. We discuss several methods for identifying wallet contracts in a semi-automatic manner by looking at the deployed bytecodes and their interaction patterns. Furthermore, we differentiate characteristics of wallets in use, and group them into six types.
{"title":"Wallet Contracts on Ethereum","authors":"Monika di Angelo, Gernot Slazer","doi":"10.1109/ICBC48266.2020.9169467","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169467","url":null,"abstract":"On the blockchain, cryptocurrencies play a role similar to cash, while cryptographic tokens are a universal tool for handling rights and assets. Software wallets interact with blockchains in general and with smart contracts (on-chain programs) in particular. Some wallets are realized (partly) as smart contracts with the intent to increase trust and security by being transparent and by offering features like daily limits, approvals, multiple signatures, and recovery mechanisms.Ethereum is the most prominent platform for both, tokens and smart contracts, and thus also for wallet contracts. We discuss several methods for identifying wallet contracts in a semi-automatic manner by looking at the deployed bytecodes and their interaction patterns. Furthermore, we differentiate characteristics of wallets in use, and group them into six types.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121861058","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169390
Q. Lu, M. Staples, Hugo O'Connor, Shiping Chen, Adnene Guabtni
Various kinds of certificates are used in international trade, and it is important for trade participants to know about their authenticity and status. One example are phytosanitary certificates, which record that exported plant-based materials meet biosecurity requirements of destination countries. An electronic "ePhyto" certificate system is being developed to be operated by the United Nations (UN). An ePhyto certificate is transmitted from the national plant protection organisation (NPPO) of the exporting country to the NPPO of the importing country. The UN system provides a secure communication channel between pre-registered NPPOs. However, industry participants who are not connected to the UN system are not able to confirm the authenticity of an ePhyto certificate, and whether that ePhyto certificate has been revoked or reissued. In this paper, we describe a blockchain-based system and its software architecture that could augment the emerging ePhyto certificate system by adding a tamper-proof for public users to check the authenticity and status of ePhyto certificates.
{"title":"Software Architecture for Blockchain-based Trade Certificate Systems","authors":"Q. Lu, M. Staples, Hugo O'Connor, Shiping Chen, Adnene Guabtni","doi":"10.1109/ICBC48266.2020.9169390","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169390","url":null,"abstract":"Various kinds of certificates are used in international trade, and it is important for trade participants to know about their authenticity and status. One example are phytosanitary certificates, which record that exported plant-based materials meet biosecurity requirements of destination countries. An electronic \"ePhyto\" certificate system is being developed to be operated by the United Nations (UN). An ePhyto certificate is transmitted from the national plant protection organisation (NPPO) of the exporting country to the NPPO of the importing country. The UN system provides a secure communication channel between pre-registered NPPOs. However, industry participants who are not connected to the UN system are not able to confirm the authenticity of an ePhyto certificate, and whether that ePhyto certificate has been revoked or reissued. In this paper, we describe a blockchain-based system and its software architecture that could augment the emerging ePhyto certificate system by adding a tamper-proof for public users to check the authenticity and status of ePhyto certificates.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128274746","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169425
Chunyu Mao, Anh-Duong Nguyen, W. Golab
Blockchain has become a promising technology in distributed systems in recent years, but scalability remains a major problem. The traditional approach to scalability, namely sharding, does not solve the problem easily because the process of interleaving blocks stored in different shards to create a unified master ledger introduces overhead. This paper examines two techniques for interleaving the shards of permissioned blockchains, which we refer to as strong temporal coupling and weak temporal coupling. We implement these techniques in a prototype system with a Bitcoin-like transaction structure, using the EPaxos consensus protocol for transaction ordering. Our experimental results show that strong coupling can achieve lower latency as compared to weak coupling but same level of peak throughput. However, strong coupling requires all shards to grow at the same rate, and cannot tolerate any shard failure. In contrast, the higher latency of weak coupling is because of the consensus strategy it uses to order the blocks. However, if shard failure occurs, weak coupling can still make progress without stalling the whole system.
{"title":"Performance and Fault Tolerance Trade-offs in Sharded Permissioned Blockchains","authors":"Chunyu Mao, Anh-Duong Nguyen, W. Golab","doi":"10.1109/ICBC48266.2020.9169425","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169425","url":null,"abstract":"Blockchain has become a promising technology in distributed systems in recent years, but scalability remains a major problem. The traditional approach to scalability, namely sharding, does not solve the problem easily because the process of interleaving blocks stored in different shards to create a unified master ledger introduces overhead. This paper examines two techniques for interleaving the shards of permissioned blockchains, which we refer to as strong temporal coupling and weak temporal coupling. We implement these techniques in a prototype system with a Bitcoin-like transaction structure, using the EPaxos consensus protocol for transaction ordering. Our experimental results show that strong coupling can achieve lower latency as compared to weak coupling but same level of peak throughput. However, strong coupling requires all shards to grow at the same rate, and cannot tolerate any shard failure. In contrast, the higher latency of weak coupling is because of the consensus strategy it uses to order the blocks. However, if shard failure occurs, weak coupling can still make progress without stalling the whole system.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"54 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116332453","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}
Pub Date : 2020-05-01DOI: 10.1109/ICBC48266.2020.9169470
Marko Suvajdzic, James C. Oliverio, Angelos Barmpoutis, Liam Wood, Paul Burgermeister
Discover DaVinci is a novel augmented reality system that incorporates blockchain technology with experiential learning to engage participants in an interactive discovery of Leonardo da Vinci’s ouvre. In the true spirit of this "Renaissance man", Discover DaVinci explores new ideas and technologies "ahead of their time".
{"title":"Discover DaVinci – A Gamified Blockchain Learning App","authors":"Marko Suvajdzic, James C. Oliverio, Angelos Barmpoutis, Liam Wood, Paul Burgermeister","doi":"10.1109/ICBC48266.2020.9169470","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169470","url":null,"abstract":"Discover DaVinci is a novel augmented reality system that incorporates blockchain technology with experiential learning to engage participants in an interactive discovery of Leonardo da Vinci’s ouvre. In the true spirit of this \"Renaissance man\", Discover DaVinci explores new ideas and technologies \"ahead of their time\".","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"468 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133431960","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}
Blockchain is a service operated by a peer-to-peer type distributed network, and protocol control such as JSON-RPC is implemented as the interface for flexibility and operability. However, attacks that use protocol control against vulnerable and unmanaged interfaces have been reported. One of the methods to track cyber attacks on such a malicious user’s network service is a honeypot that imitates the service and acquires attacker’s behavior information. In this research, focusing on the Ethereum network, the behavior of malicious users is clarified using malicious communication history sent to simple honeypots installed in nine countries, Ethereum network information and darknet arrival packets. By analyzing these, the behavior of attackers and the tendency of requests were elucidated, and primary safety measures were established.
{"title":"Profiling of Malicious Users Using Simple Honeypots on the Ethereum Blockchain Network","authors":"Kazuki Hara, Teppei Sato, Mitsuyoshi Imamura, Kazumasa Omote","doi":"10.1109/ICBC48266.2020.9169469","DOIUrl":"https://doi.org/10.1109/ICBC48266.2020.9169469","url":null,"abstract":"Blockchain is a service operated by a peer-to-peer type distributed network, and protocol control such as JSON-RPC is implemented as the interface for flexibility and operability. However, attacks that use protocol control against vulnerable and unmanaged interfaces have been reported. One of the methods to track cyber attacks on such a malicious user’s network service is a honeypot that imitates the service and acquires attacker’s behavior information. In this research, focusing on the Ethereum network, the behavior of malicious users is clarified using malicious communication history sent to simple honeypots installed in nine countries, Ethereum network information and darknet arrival packets. By analyzing these, the behavior of attackers and the tendency of requests were elucidated, and primary safety measures were established.","PeriodicalId":420845,"journal":{"name":"2020 IEEE International Conference on Blockchain and Cryptocurrency (ICBC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132669804","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}
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