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An increasingly important trend in the design of industry-strength embedded systems is the integration of multiple services with varying criticality levels into a common computing platform. Such systems are characterized as mixed-criticality multiservice systems (MCMSs). An MCMS has to survive in rigorous environments posed by industry-level requirements. Such survival, however, is becoming continuously more challenging due to the growing system complexity and integrating more and more services. While existing works typically target reliability-driven design optimization to improve the system robustness rather than deal with the surviving problem of the system in extreme physical environments, this paper addresses the problem by enabling the service capability transitions of an MCMS to adapt to the environments. This paper proposes a service capability model to capture the importance of functional modules for the criticality of different services. A model-based service-capability transition mechanism is designed to automatically identify the maximum allowed service capability under a given physical environment. A case study of the proposed techniques was performed on an industrial Ethernet switch which is a typical MCMS, to validate the capability of adaptation to high and low temperatures. The experimental results demonstrate the significant potential of our approach to improve system survivability under extreme physical environments. [ABSTRACT FROM AUTHOR]

Time-sensitive networking (TSN) is a set of extended standards for the IEEE 802.3 Ethernet under development by the IEEE 802.1 TSN task group. TSN depends on two key components, scheduling and fault tolerance, to provide real-time and reliable transmission. There is a strong motivation to replace the widely used field-buses with TSNs in industrial networking applications. However, industrial network devices are typical application-specific embedded systems with limited memory resources. Time-sensitive (TS) transmission certainly prefers on-chip memory, which is even more scarce for embedded systems. As a result, it is critical for TSNs to develop memory-efficient switching techniques with scalable schedulability and elegant fault-tolerance support. This paper proposes a time-triggered switch-memory-switch (SMS) architecture for memory-efficient TSN switches. First, based on the SMS shared memory, our architecture makes it possible to statically schedule memory allocation with full utilization for TS traffic and the remaining memory for other traffic. Compared with per-port memory, the shared memory achieves a ratio of (${n^{n}}/{n!}$) (${\approx }({e^{n}}/{\sqrt {2 \pi n}}), {n\rightarrow \infty }$), where ${n}$ is the port number, in the feasible solution space under memory constraints and thus significantly improves scheduling memory ability and flexibility. Moreover, we develop a fault-tolerance scheme for reliable transmission. It facilitates a memory-efficient implementation of the popular multiline redundancy in industrial networks. The scheme is validated by five classes of memory conflicts and a case study on two-line redundancy. [ABSTRACT FROM AUTHOR]