Smarsly, KayKaySmarsly2026-07-222026-07-222026-0626th International Conference on Computational Science, ICCS 2026https://hdl.handle.net/11420/63999Modern structural health monitoring (SHM) systems and the physical structures being monitored constitute coupled cyber-physical systems that must be protected as a whole. As a consequence, threats no longer solely stem from structural anomalies, but also from internal SHM system faults and, in particular, from cyberattacks that may falsify sensor data, disrupt communication, or even sabotage critical infrastructure. The capabilities required to withstand the threats are often subsumed under the notion of a “digital immune system”. However, prior work on digital immune systems either targets other application domains that cannot be directly transferred to civil infrastructure or uses the label “digital immune system” as a buzzword without systematically mapping biological immune functions to digital counterparts. This paper presents a biologically inspired reference architecture for digital immune systems for civil infrastructure, defines and formally specifies the threat categories relevant to coupled cyber-physical SHM systems, introduces a compact illustrative sensor-fault scenario, and derives implementation-oriented recommendations intended to support computational modeling and simulation. Explicitly drawing from the biological immune functions, the reference architecture includes innate and adaptive layers, distinguishing between cellular-oriented, local modules and humoral-oriented, global elements. The architecture is intended to serve as a generally applicable blueprint for designing digital immune systems for civil infrastructure, aiming to advance cyber-physical SHM systems at the interface between civil engineering and computer science.enArtificial immune systemsComputational modelingCyber-physical systemsCybersecurityDigital immune systemsFault diagnosisStructural health monitoringTechnology::617: Surgery, Regional Medicine, Dentistry, Ophthalmology, Otology, AudiologyComputer Science, Information and General Works::005: Computer Programming, Programs, Data and Security::005.8: Computer SecurityConference Paper10.1007/978-3-032-29909-3_10