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Announcement - Agenda - Paper Presentations - Kickstart Sessions - Panel

Combining Linux and a softPLC in a single system stands to reason: Linux offers many facilities that modern PLCs are expected to support. However, existing Linux-based softPLC implementations so far have always placed the PLC ''on top'' of the Linux kernel, so its functional reliability depends on the correctness of the kernel. Due to its size, the Linux kernel can not be exhaustively validated or even proven correct. This has hampered applicability of the concept to safety-critical PLC systems. The approach described in this paper puts Linux and a softPLC ''side by side'' on top of a small microkernel, thus the two subsystems can coexist safely without being forced to depend on each other. In this way, the trusted code base of the PLC is reduced by several orders of magnitude, thereby enabling its certification according to applicable standards for safety-critical systems.