Resource efficient dynamic agreement and replication

目前的趋势是网络物理系统，这引起了许多问题和关切，特别是安全和安保问题。研究单位控制并发变化（CCC）的目的是回答这些开放问题的一个特定子集，即如何利用软件的灵活性及其重新配置和更新的机会，同时仍然保留必要的关键任务非功能属性。子项目A3“资源高效的动态协议和复制”应对挑战，为CCC控制的域的联合和可靠重新配置提供基础，并为分散在多个CCC域的应用程序提供容错协调和复制支持。因此，故障不限于崩溃，而是取决于从硬件引起的故障（例如，位翻转）到故意和协调的恶意行为的极端的场景范围。在技术层面上，A3子项目的目标是为资源有效的拜占庭协议提供新的协议，这些协议是针对资源受限的嵌入式系统定制的。根据使用情况，目标是无线和移动的设置。虽然第一种方式面临的挑战是，与协议协议的典型部署环境相比，可靠性较低，限制更多，但多宿主的预期智能使用可能会减轻这些影响。此外，移动的设置通常需要解决频繁的成员资格变化，这对现有的拜占庭协议提出了挑战，并且迄今为止一直被忽视。作为CCC基础设施的核心部分之一，更新的在线验证对于所有重要的情况都需要资源密集型的规划过程。简单地复制此功能以协调多个域的重新配置将浪费大量资源。因此，将为这一核心任务设计和评价专门的复制计划。后者将与模拟环境范围内的已开发协议支持以及由一组嵌入式系统组成的物理部署相结合。

There is an ongoing trend towards cyber-physical systems, which raises many questions and concerns prominently including safety and security matters. The research unit Controlling Concurrent Change (CCC) aims at answering a specific subset of these open issues, namely how the flexibility of software and its opportunity for reconfiguration and updates can be utilized, while still preserving essential mission-critical non-functional properties. The subproject A3 "Resource efficient dynamic agreement and replication" addresses the challenge to provide a basis for joint and reliable reconfiguration of CCC-controlled domains and offers applications that are dispersed over multiple CCC-domains support for fault-tolerant coordination and replication. Thereby, faults are not limited to crashes but depending on the scenario range from hardware induced malfunctioning (e.g. bit flips) up to the extreme of intentional and coordinated malicious behavior. At the technical level the A3 subproject aims at providing novel protocols for resource efficient Byzantine agreement that are tailored towards resource constrained embedded systems. Depending on the use case wireless and mobile settings are targeted. While the first poses the challenge of being less reliable and more constrained compared to the typical deployment environment of agreement protocols the intended smart use of multi-homing might mitigate these effects. Mobile settings furthermore typically demand to address frequent membership changes, which poses a challenge for existing Byzantine agreement protocols and so far has been neglected. As one of the core parts of the CCC infrastructure, the online validation of an update requires for all non-trivial cases a resource-intensive planning process. Naively replication of this functionality for coordinated reconfiguration of multiple domains would waste vast amounts of resources. Accordingly tailored replication schemes for this core task will be devised and evaluated. The latter will be performed in combination with the developed agreement support in scope of simulated environments as well as a physical deployment consisting of a set of embedded systems.