互联网的普及对计算范式的发展产生了重大影响。随着新一代信息技术基础设施的不断完善,学术界与工业界在持续探索新的计算范式,以实现对算力的充分挖掘。海量物联网(internet of things,IoT)设备产生的庞大数据逐渐超出了以云服务器为...互联网的普及对计算范式的发展产生了重大影响。随着新一代信息技术基础设施的不断完善,学术界与工业界在持续探索新的计算范式,以实现对算力的充分挖掘。海量物联网(internet of things,IoT)设备产生的庞大数据逐渐超出了以云服务器为代表的高性能后端的处理能力,边缘计算(edge computing)通过云边端协同缓解了这一问题,但仍存在算力利用率低、算/存容错性低,以及计算资源整合度低等困难与挑战。元计算(meta computing)是一种新型计算范式,旨在零信任基础上,打破算力藩篱,整合网络中所有的可用计算与存储资源,为各项任务提供高效、安全可靠、可容错的个性化服务,同时利用密码学技术保护敏感数据信息,确保用户数据的隐私性,保证任务结果的准确性与可靠性,最终实现“对任何一个人或者一项任务整个网络就是一台计算机”,即“网络即计算机(network-as-a-computer,NaaC)”,也称为“元计算机”(meta computer)。本文分析了元计算的三大功能目标,据此提出了一个包含云边端资源、设备管理与零信任计算管理模块的元计算机架构。在该架构中,设备管理模块将海量异构设备的资源抽象为可以自由操控的对象,零信任计算管理模块则根据用户任务需求直接调度计算资源,完成强容错的计算任务并输出可验证的计算结果,最后进行结算。本文在剖析元计算机架构与功能特性的基础上,分析了实现元计算机面临的技术挑战,给出了元计算“从局部过渡到整体”的发展思路,预测了元计算的未来应用场景,为未来元计算的落地与发展规划出合理的突破路线。展开更多
Scalability has long been a major challenge of cryptocurrency systems,which is mainly caused by the delay in reaching consensus when processing transactions on-chain.As an effective mitigation approach,the payment cha...Scalability has long been a major challenge of cryptocurrency systems,which is mainly caused by the delay in reaching consensus when processing transactions on-chain.As an effective mitigation approach,the payment channel networks(PCNs)enable private channels among blockchain nodes to process transactions off-chain,relieving long-time waiting for the online transaction confirmation.The state-of-the-art studies of PCN focus on improving the efficiency and availability via optimizing routing,scheduling,and initial deposits,as well as preventing the system from security and privacy attacks.However,the behavioral decision dynamics of blockchain nodes under potential malicious attacks is largely neglected.To fill this gap,we employ the game theory to study the characteristics of channel interactions from both the micro and macro perspectives under the situation of channel depletion attacks.Our study is progressive,as we conduct the game-theoretic analysis of node behavioral characteristics from individuals to the whole population of PCN.Our analysis is complementary,since we utilize not only the classic game theory with the complete rationality assumption,but also the evolutionary game theory considering the limited rationality of players to portray the evolution of PCN.The results of numerous simulation experiments verify the effectiveness of our analysis.展开更多
基金The work was partially supported by the National Key Research and Development Program of China under Grant No.2019YFB2102600the National Natural Science Foundation of China under Grant Nos.62122042,61971269 and 61832012.
文摘Scalability has long been a major challenge of cryptocurrency systems,which is mainly caused by the delay in reaching consensus when processing transactions on-chain.As an effective mitigation approach,the payment channel networks(PCNs)enable private channels among blockchain nodes to process transactions off-chain,relieving long-time waiting for the online transaction confirmation.The state-of-the-art studies of PCN focus on improving the efficiency and availability via optimizing routing,scheduling,and initial deposits,as well as preventing the system from security and privacy attacks.However,the behavioral decision dynamics of blockchain nodes under potential malicious attacks is largely neglected.To fill this gap,we employ the game theory to study the characteristics of channel interactions from both the micro and macro perspectives under the situation of channel depletion attacks.Our study is progressive,as we conduct the game-theoretic analysis of node behavioral characteristics from individuals to the whole population of PCN.Our analysis is complementary,since we utilize not only the classic game theory with the complete rationality assumption,but also the evolutionary game theory considering the limited rationality of players to portray the evolution of PCN.The results of numerous simulation experiments verify the effectiveness of our analysis.
