CSR-PDOS: Availability-Aware Services

CSR-PDOS：可用性感知服务

• 批准号: 0615086
• 负责人: Brian Noble
• 金额: $ 30万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0615086&HistoricalAwards=false
• 关键词: CSR; PDOS; Availability; Aware; Services

As distributed systems are deployed across machines free to opt in or out at any time, host availability is a first-order concern. Systems typically deal with availability in a reactive way, making little distinction between machines with different availability behaviors. In short, current systems view fluctuating availability as a problem. This project views availability as an opportunity, by predicting the availability of many individual hosts in a larger collective. By using a competitive tournament of predictors, the project is able to predict the availability of many nodes even in completely unmanaged networks. The research effort applies these predictors in three domains. In the first, epidemic propagation, the project augments current viral infection models to consider availability in addition to topology. The second application is delay-tolerant networking. By using availability prediction as a practical contact oracle, one can improve end-to-end latency and routing efficiency. As a third application, the project applies availability prediction to DHT-based storage and archival networks. By biasing placement of some replicas towards highly available nodes, churn-induced document transfer is reduced and overall system availability improved. By ugmenting the maintenance protocols with availability predictions, network overhead is further reduced.

由于分布式系统部署在可以随时自由选择加入或退出的机器上，因此主机可用性是首要考虑的问题。系统通常以反应方式处理可用性，对具有不同可用性行为的机器几乎没有区别。简而言之，当前系统将可用性波动视为一个问题。 该项目通过预测较大集体中许多单独主机的可用性，将可用性视为一个机会。通过使用预测器的竞争性锦标赛，即使在完全不受管理的网络中，该项目也能够预测许多节点的可用性。研究工作将这些预测因子应用于三个领域。 第一个是流行病传播，该项目增强了当前的病毒感染模型，除了拓扑之外还考虑了可用性。 第二个应用是延迟容忍网络。 通过将可用性预测用作实用的联系预言机，可以改善端到端延迟和路由效率。 作为第三个应用，该项目将可用性预测应用于基于 DHT 的存储和归档网络。 通过将一些副本偏向于高可用节点的放置，可以减少搅动引起的文档传输并提高整体系统可用性。 通过利用可用性预测增强维护协议，网络开销进一步减少。