Resolving state inconsistency in distributed fault-tolerant real-time dynamic TDMA architectures

State consistency in safety-critical distributed systems is mandatory for synchronizing distributed decisions as found in dynamic time division multiple access (TDMA) schedules in the presence of faults. A TDMA schedule that supports networked systems making decisions at run time is sensitive to transient faults, because stations can make incorrect local decisions at run time and cause state inconsistency and collisions. We refer to this type of TDMA schedule as a dynamic TDMA schedule. Faulty decisions are especially undesirable for safety-critical systems with hard real-time constraints. Hence, real-time communication schedules must have the capability of detecting state inconsistency within a fixed amount of time. In this paper, we show through experimentation that state inconsistency is a real problem, and we propose a solution for resolving state inconsistency in TDMA schedules.

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