Byzantine fault tolerance is a sub-field of fault tolerance research inspired by the Byzantine Generals' Problem, which is a generalized version of the Two Generals' Problem. The object of Byzantine fault tolerance is to be able to defend against Byzantine failures, in which components of a system fail in arbitrary ways (i.e. , not just by stopping or crashing but by processing requests incorrectly, corrupting their local state, and/or producing incorrect or inconsistent outputs.).
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