Resource-Efficient Fault and Intrusion Tolerance

基于互联网的服务在我们的社会中发挥着越来越重要的作用，并取代了传统的基础设施。与此同时，这种服务的复杂性以及用于提供它们的硬件和软件的复杂性不断增加。尽管有先进的开发技术，但这导致了越来越多的系统故障。此外，漏洞允许恶意攻击者从远程攻击这些服务。在最好的情况下，服务只是崩溃，但在其他情况下，服务的完整性可能会受到损害，不正确的数据可能会被分发。该项目的目标是为资源高效的拜占庭容错服务提供操作和开发支持。基于该项目第一阶段的成果，建议的第二阶段包括两个主要研究领域：（1）如果BFT系统应该容忍灾难，它们必须分布在世界各地。然而，只有当系统能够适应这种设置的特殊条件时，只有当系统是地理适应性的时，才可以有效地使用现有资源并且可以实现所需的性能。在该项目的过程中所采取的措施从副本角色的动态分配和自适应状态转移到整个系统的广泛重新配置。(2)为了促进这种灵活性，但首先是为了有效地利用本地资源，第二个研究领域致力于开发能够适应执行它们的平台特性的副本。从严格分解所采用的协议的单个关注点和新颖的执行模型开始，将设计一种架构，该架构可以利用多核系统和即将到来的非易失性主存的潜力来提高BFT副本的效率。总的来说，该项目的第二阶段旨在实现资源高效的地理适应性，平台感知的BFT系统，能够最小化甚至克服拜占庭容错需求与当前建议的有限实用性之间的差距。

Internet-based services play a more and more central role in our society and supersede conventional infrastructures. At the same time, the complexity of such services as well as the complexity of the hard- and software employed to provide them continuously increases. Despite advanced development techniques, this leads to a growing number of system failures. Moreover, vulnerabilities allow malicious adversaries to attack these services from remote. In the best case, services simply crash but in other cases, the integrity of services can get compromised and incorrect data can gets distributed.Objective of this project is the provisioning of operating and development support for resource-efficient Byzantine fault-tolerant services. Based on results yielded by the first phase of the project, the proposed second phase comprises two main research areas: (1) If BFT systems are supposed to tolerate catastrophes, they have to be distributed worldwide. However, only if the system is able to adapt to the special conditions of such a setting, only if the system is geo-adaptive, existing resources can be used efficiently and required performance can be achieved. The measures strived for in the course of that project reach from a dynamic assignment of roles for replicas and an adaptive state transfer through to extensive reconfigurations of the whole system. (2) In order to facilitate this kind of flexibility, but first of all in order to make efficient use of local resources, the second research area is dedicated to the development of replicas that are able to adapt to the peculiarities of the platforms executing them. Starting from a strict decomposition of single concerns of the employed protocols and from novel execution models, an architecture is to be devised that can exploit the potential of multi-core systems and upcoming non-volatile main memories to improve the efficiency of BFT replicas.In total, the second phase of this projects aims at a resource-efficient geo-adaptive, platform-aware BFT system that is able to minimize or even overcome the gap between the demand for Byzantine fault tolerance and the confined practicability of current proposals.