The measurement of the speed of light one-way can be easily conceived since we can consider a rod with length l_1 between the extremities A´ and B´ and emit light from A´ to B´ and reciprocally emit light from B´ to A´. If we measure the time A´B´ and the time B´A´ we know the speed of light A´B´ and B´A´. However, standard approach affirm astonishingly that this is not possible. Because we need to know the speed of light to synchronize the clocks at A´ and B´, to measure the times A´B’ and B´A´. Why? Because standard approach accept the necessity to have synchronized clocks. And astonishingly also affirm that the one-way speed of light one-way is the two-way speed of light measured in one-clock with the value c in vacuum. In the following approach we defend that this standard approach can not subsist based on the conceptualization of the measurement one-way. For this we use a new method using a gap of synchronization that standard approach can not be aware.