During the concept design of complex networked systems, concept developers have to assure that the choice of hardware modules and the topology of the target platform will provide adequate resources to support the needs of the application. For example, future-generation aerospace systems need to consider multiple requirements, with many trade-offs, foreseeing rapid technological change and a long time span for realization and service. For that purpose, we introduce NetGAP, an automated 3-phase approach to synthesize network topologies and support the exploration and concept design of networked systems with multiple requirements including dependability, security, and performance. NetGAP represents the possible interconnections between hardware modules using a graph grammar and uses a Monte Carlo Tree Search optimization to generate candidate topologies from the grammar while aiming to satisfy the requirements. We apply the proposed approach to the synthetic version of a realistic avionics application use case and show the merits of the solution to support the early-stage exploration of alternative candidate topologies. The method is shown to vividly characterize the topology-related trade-offs between requirements stemming from security, fault tolerance, timeliness, and the "cost" of adding new modules or links. Finally, we discuss the flexibility of using the approach when changes in the application and its requirements occur.

翻译：在复杂网络化系统的概念设计阶段，概念设计者必须确保硬件模块的选择及目标平台的拓扑结构能够提供充足资源以支撑应用需求。例如，未来航空航天系统需要在权衡多种需求的同时，预判快速技术变革与漫长的实现及服役周期。为此，我们提出NetGAP——一种自动化三阶段方法，用于综合网络拓扑结构，并支持含可信性、安全性和性能等多重需求的网络化系统探索与概念设计。NetGAP采用图文法表示硬件模块间的潜在互连关系，并利用蒙特卡洛树搜索优化算法，从文法中生成候选拓扑结构，同时力求满足各项需求。我们将该方法应用于真实航电应用场景的合成版本，证明了该方案在支持早期备选拓扑结构探索方面的优势。实验表明，该方法能生动刻画安全、容错、时效性等需求与新增模块或链路"成本"之间的拓扑相关权衡。最后，我们讨论了应用需求变更时采用该方法的灵活性。