Integrated and Modular Systems for Commercial ... - Nonstop Systems

Integration issues (cont’d)
• loss of a shared resource affects multiple functions → potential for
single-point/common-mode failure due to contaminated data flow,
control flow, resource:
� fault tolerance required to meet availability & integrity req’s
� partitioning must be part of architecture and independent of application
software
� increased importance of FMEA, FHA, etc.
• mixed levels of criticality: certify at highest level, or certify the
partitioning protection.
• criticality of the “whole” may be higher than that of “stand-alone”
parts due to effects of loss (3x “essential” → “critical” ?)
• technology readiness (risk): development of fault-tolerant integrated
architectures drives a/c level schedules (be mature at a/c program go-ahead)
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