This read-write timer sets the Error_Detect_Timeout Value (E_D_TOV), in milliseconds, that FxPorts use to decide when a Fibre Channel error condition has occurred, and it must be smaller than the fabric's fcTimerDstov value. An administrator keeps this consistent across all switches in the fabric so that error detection timing behaves predictably fabric-wide. For example, setting fcTimerEdtov higher than fcTimerDstov on a switch would violate the required ordering between the two timers and could cause unpredictable error handling.