区块链技术因其不可篡改和可追溯性等特点,在数据完整性保护方面具有很大优势。在数据量较大的日志数据保护场景中,数据的真实性、完整性、机密性都有很高要求,而现有方法并不能兼顾。因此,设计了一种基于区块链智能合约的日志安全保护...区块链技术因其不可篡改和可追溯性等特点,在数据完整性保护方面具有很大优势。在数据量较大的日志数据保护场景中,数据的真实性、完整性、机密性都有很高要求,而现有方法并不能兼顾。因此,设计了一种基于区块链智能合约的日志安全保护模型,提出日志数据微观保护环境(micro log data protect environment,MiLDPE)和日志数据宏观保护环境(macro log data protect environment,MaLDPE)的概念。MiLDPE是用硬件SGX技术实现可信计算的区块链节点,其确保日志数据仅能在产生它的节点上审计。MaLDPE是一个多MiLDPE节点组成的去中心化区块链集群,由一组智能合约实现日志数据访问控制,并通过随机节点选择算法保障日志数据的完整性和机密性。通过大量实验研究,证实该模型性能达到了预期要求。展开更多
With the advent of big data,the demand for computing has been increasing in a very large scale for the past decade,so geographically distributed data centers are erected in the direction of cloud computing development...With the advent of big data,the demand for computing has been increasing in a very large scale for the past decade,so geographically distributed data centers are erected in the direction of cloud computing development. A Lyapunov optimization approach is considered for the problem of minimizing energy cost for distributed Internet data centers( IDCs). By capturing the power cost of servers and cooling systems,the Lyapunov optimization technique is formulated to design a decisive strategy that offers provable power cost minimization and Qo S guarantees. The algorithm performance and effectiveness are validated via simulations driven by real world traces.展开更多
The integrated modular avionics （IMA） architecture is an open standard in avionics industry, in which the number of functionalities implemented by software is greater than ever before. In the IMA architecture, the r...The integrated modular avionics （IMA） architecture is an open standard in avionics industry, in which the number of functionalities implemented by software is greater than ever before. In the IMA architecture, the reliability of the avionics system is highly affected by the software applications. In order to enhance the fault tolerance feature with regard to software application failures, many industrial standards propose a layered health monitoring/fault management （HM/FM） scheme to periodically check the health status of software application processes and recover the malfunctioning software process whenever an error is located. In this paper, we make an analytical study of the HM/FM system for avionics application software. We use the stochastic Petri nets （SPN） to build a formal model of each component and present a method to combine the components together to form a complete system model with respect to three interlayer query strategies. We further investigate the effectiveness of these strategies in an illustrative system.展开更多
文摘区块链技术因其不可篡改和可追溯性等特点,在数据完整性保护方面具有很大优势。在数据量较大的日志数据保护场景中,数据的真实性、完整性、机密性都有很高要求,而现有方法并不能兼顾。因此,设计了一种基于区块链智能合约的日志安全保护模型,提出日志数据微观保护环境(micro log data protect environment,MiLDPE)和日志数据宏观保护环境(macro log data protect environment,MaLDPE)的概念。MiLDPE是用硬件SGX技术实现可信计算的区块链节点,其确保日志数据仅能在产生它的节点上审计。MaLDPE是一个多MiLDPE节点组成的去中心化区块链集群,由一组智能合约实现日志数据访问控制,并通过随机节点选择算法保障日志数据的完整性和机密性。通过大量实验研究,证实该模型性能达到了预期要求。
基金Supported by the National Natural Science Foundation of China(No.61502255)the Inner Mongolia Provincial Natural Science Foundation(No.2014BS0607)the Science Research Project for Inner Mongolia College(No.NJZY14064)
文摘With the advent of big data,the demand for computing has been increasing in a very large scale for the past decade,so geographically distributed data centers are erected in the direction of cloud computing development. A Lyapunov optimization approach is considered for the problem of minimizing energy cost for distributed Internet data centers( IDCs). By capturing the power cost of servers and cooling systems,the Lyapunov optimization technique is formulated to design a decisive strategy that offers provable power cost minimization and Qo S guarantees. The algorithm performance and effectiveness are validated via simulations driven by real world traces.
基金supported by the National Grand Fundamental Research Program of China (Nos. 2010CB328105, 2009CB320504)the Tsinghua University Initiative Scientific Research Programthe National Natural Science Foundation of China (Nos. 61070182,60973107, 60973144, 61173008, 61070021)
文摘The integrated modular avionics （IMA） architecture is an open standard in avionics industry, in which the number of functionalities implemented by software is greater than ever before. In the IMA architecture, the reliability of the avionics system is highly affected by the software applications. In order to enhance the fault tolerance feature with regard to software application failures, many industrial standards propose a layered health monitoring/fault management （HM/FM） scheme to periodically check the health status of software application processes and recover the malfunctioning software process whenever an error is located. In this paper, we make an analytical study of the HM/FM system for avionics application software. We use the stochastic Petri nets （SPN） to build a formal model of each component and present a method to combine the components together to form a complete system model with respect to three interlayer query strategies. We further investigate the effectiveness of these strategies in an illustrative system.
