共查询到16条相似文献,搜索用时 142 毫秒
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讨论了基于云计算的在线系统的灾难恢复的技术,主要从规划备份策略出发,提出了还原事务日志、还原页、文件和文件组的方法,给出了分页还原和从数据库快照中还原数据的场景和方法。适时进行数据恢复和故障演习,采取全方位、多层次的数据备份和灾难恢复技术,保护在线系统的安全。 相似文献
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部分补偿和完全补偿是事务工作流失效恢复的传统补偿方法,对于长期运行且结构复杂的事务工作流,失效时需要补偿至静态定义的某一活动甚至起始活动,因此代价较大.给出了事务工作流的概念模型,提出了一种层次式的失效恢复算法.与传统方法相比,允许事务性或者非事务性子过程同时存在;将工作流看作由嵌套结构的子过程组成,而不是一个平坦流图;基于执行历史而不是工作流定义进行补偿,可简化循环结构的恢复.该算法针对活动的恢复策略进行层次式的向上规约处理,动态确定补偿终止点,可有效减小补偿域.证明了算法的正确性,性能分析表明其性能通常优于非层次的失效恢复算法,讨论了算法的实现. 相似文献
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针对端射阵机载雷达杂波谱存在的距离非平稳问题,提出了一种基于稀疏恢复的距离模糊杂波抑制方法。该方法首先通过稀疏恢复理论建立杂波回波数据的欠定方程,并结合欠定系统局灶解法求得杂波的空时谱分布,重构出每个距离门的杂波协方差矩阵;然后,以最远可检测距离单元为参考单元对杂波数据进行补偿,并进行目标约束;最后,基于补偿后的数据进行空时自适应杂波抑制处理。与传统端射阵距离模糊杂波谱补偿方法相比,该方法的杂波协方差矩阵估计精度高,杂波抑制性能更优。理论分析和仿真结果验证了该方法的有效性。 相似文献
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为了实现未知退化类型条件下的图像恢复,提出了一种基于低秩先验非局部匹配的高光谱图像恢复方法。该恢复策略将结构相似性指数度量作为数据保真度项,核范数作为正则化项,从而能够使用单一算法解决延迟和信号相关的退化形式,能够处理加性高斯噪声、与信号相关的泊松噪声、混合泊松-高斯噪声,并且能够恢复被截止期和条纹损坏的高光谱图像。通过多个数据集实验结果证明了提出方法具有较好的恢复效果。 相似文献
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为了对自动广播相关监视(ADS-B)攻击数据进行弹性恢复,确保空情态势感知信息的持续可用性,该文提出针对ADS-B攻击数据的弹性恢复方法。基于前置的攻击检测机制,获取当前ADS-B量测数据序列和预测数据序列,并在此基础上构建偏差数据序列、差分数据序列和邻近密度数据序列。依托偏差数据构建恢复向量,依托差分数据挖掘攻击数据的时序特性,依托邻近密度数据挖掘攻击数据的空间特性。通过整合3种数据序列构建弹性恢复策略并确定恢复终止点,实现对攻击影响的弱化,将ADS-B攻击数据向正常数据方向进行定向恢复。通过对6种典型攻击样式的实验分析,证明该弹性恢复方法能够有效恢复ADS-B攻击数据,削弱数据攻击对监视系统的影响。 相似文献
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H.Garcia-Molina等人提出了用于解决长事务问题的Sagas模型,但Sagas模型的事务补偿过程会撤销整个长事务,另外每个子事务都必须具有补偿子事务,这两个缺陷大大影响了Sagas模型的执行效率和适用性.文中提出了一种基于执行历史的层次式的失效恢复算法.该算法动态确定补偿终止点,可有效减小补偿域. 性能分析表明其性能通常优于非层次的失效恢复算法. 相似文献
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The fiber distributed data interface (FDDI) is an ANSI draft proposed standard for a 100 Mbit/s fiber-optic token ring. The FDDI timed token access protocol provides dynamic adjustment of the load offered to the ring, with the goal of maintaining a specified token rotation time and of providing a guaranteed upper bound on time between successive arrivals of the token at a station. FDDI also provides automatic recovery when errors occur. The bound on time between successive token arrivals is guaranteed only if the token rotates quickly enough to satisfy timer requirements in each station when all ring resources are functioning properly. Otherwise, recovery would be initiated unnecessarily. The purpose of this paper is to prove that FDDI timing requirements are satisfied, i.e., the token rotates quickly enough to prevent initiation of recovery unless there is failure of a physical resource or unless the network management entity within a station initiates the recovery process. 相似文献
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Recently, mobile phones have been recognized as the most convenient type of mobile payment device. However, they have some security problems; therefore, mobile devices cannot be used for unauthorized transactions using anonymous data by unauthenticated users in a cloud environment. This paper suggests a mobile payment system that uses a certificate mode in which a user receives a paperless receipt of a product purchase in a cloud environment. To address mobile payment system security, we propose the transaction certificate mode (TCM), which supports mutual authentication and key management for transaction parties. TCM provides a software token, the transaction certificate token (TCT), which interacts with a cloud self‐proxy server (CSPS). The CSPS shares key management with the TCT and provides simple data authentication without complex encryption. The proposed self‐creating protocol supports TCM, which can interactively communicate with the transaction parties without accessing a user's personal information. Therefore, the system can support verification for anonymous data and transaction parties and provides user‐based mobile payments with a paperless receipt. 相似文献
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Linux平台远程逻辑卷复制系统的灾难恢复策略 总被引:4,自引:1,他引:3
在存储管理中,数据保护是重要的一环.本文提出了一种基于Linux平台远程逻辑卷复制系统的灾难恢复策略,并论述了它的基本原理及实现方法.该灾难恢复策略保证了本地系统的数据卷在遭受灾难的情况下,可以被远程系统进行接管,并在适当时候根据远程数据卷实现本地数据的有效恢复,大大提高了数据保护能力,并在一定程度上降低了管理开销. 相似文献
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The Label Distribution Protocol (LDP) needs to recover its state information after a control plane failure, so that the established connections in the data plane are not disrupted by any new connection set-up. We propose a backup mechanism to store the LDP state information in an upstream neighbour node. The backup LDP state information is synchronized with the original LDP state information in a downstream node when the LDP sets up or tears down connections. Then, we propose a two-step LDP state information recovery, which uses a fast LDP state information recovery to recover what labels are idle before a control plane failure, and a detailed LDP state information recovery to fully recover all LDP state information. The fast LDP state information recovery is realized as part of the LDP initialization, allowing a restarting LDP session to process new connection set-up requests as soon as possible, without interfering existing connections. The detailed LDP state information recovery performs in the background in parallel to the normal LDP operations. When an LDP connection teardown requires the LDP state information that has not yet been recovered, an on-demand query based LDP state information recovery is conducted. The performance analysis demonstrates that our proposal achieves fast LDP recovery for the core label state information. It features scalable LDP state information storage and recovery by only involving a pair of neighbour nodes. 相似文献