Byzantine Agreement with Median Validity
نویسندگان
چکیده
We introduce a stronger validity property for the byzantine agreement problem with orderable initial values: The median validity property. In particular, the decision value is required to be close to the median of the initial values of the non-byzantine nodes. The proximity to the median scales with the desired level of fault-tolerance: If no fault-tolerance is required, algorithms have to decide for the true median. If the number of failures is maximal, algorithms must still decide on a value within the range of the input values of the non-byzantine nodes. We present a deterministic algorithm satisfying this property for n ≥ 3t + 1 within t + 1 phases, where t is the maximum number of byzantine nodes and n is the total number of nodes. 1998 ACM Subject Classification F.1.1 Models of Computation
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