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Real-Time Executive for Multiprocessor Systems (RTEMS) is a real-time operating system used by the Experimental Physics and Industrial Control System (EPICS) open-source software for high-precision scientific instruments such as particle accelerators and telescopes. EPICS relies on the networking capabilities of RTEMS for microcontrollers that need to meet real-time constraints. However, the networking available in RTEMS either lacks the necessary drivers to be fully operational or lacks security features required in modern networks. In this paper, we introduce a modular networking architecture for RTEMS by separating the network software implementation and device drivers from the RTEMS kernel to provide them as a static library for applications to use. This networking-as-a-library concept provides application developers with better capabilities to select the network features needed for their target application and to keep their networking software undated and secure. 

Several cyber-physical systems use real-time restart-based embedded systems with the Simplex architecture to provide safety guarantees against system faults. Some approaches have been developed to protect such systems from security violations too, but none of these approaches can prevent an adversary from modifying the operating system or application code to execute an attack that persists even after a reboot. In this work, we present a secure boot mechanism to restore real-time restart-based embedded systems into a secure computing environment after every restart. We analyze the delay introduced by the proposed security feature and present preliminary results to demonstrate the viability of our approach using an open-source bootloader and real-time operating system. 

Arbitrary processor affinities are used in multiprocessor systems to specify the processors on which a task can be scheduled. However, affinity constraints can prevent some high priority real-time tasks from being scheduled, while lower priority tasks execute. This paper presents an implementation and evaluation of the Strong Arbitrary Processor Affinity scheduling on a real-time operating system, an approach that not only respects user-defined affinities, but also supports migration of a higher priority task to allow execution of a task limited by affinity constraints. Results show an improvement in response and turnaround times of higher priority tasks. 

In a network of mining pools that secure Bitcoin-like blockchains, it is known that a self-interested mining pool can dishonestly siphon off another pool’s mining rewards by executing a block withholding (BWH) attack. In this paper, we show that a BWH attack is always unprofitable for an initial startup period which is at least one difficulty retarget interval (approximately 14 days for Bitcoin). Furthermore, we prove that the payback period to recoup this initial startup cost is always at least as long as the initial unprofitable startup interval, and we show numerically that it can be substantially longer. Thus, the decision of whether or not to execute a BWH attack is not a dominant strategy, and the so called Miner’s Dilemma is not in fact a dilemma.