The paper experimentally investigates the performance of the Ethernet and Fast-Ethernet free space optical (FSO) communications link under the influence of the weak atmospheric turbulence. A dedicated experimental indoor atmospheric chamber is used to generate and control the turbulence conditions that affect the FSO link performance. The chamber is calibrated and the measured data are verified with the theoretical prediction. We also demonstrate methods to control the turbulence levels and determine the equivalence between the indoor and outdoor FSO links. It is also observed that the connectivity of Ethernet and Fast-Ethernet links are highly sensitive to atmospheric conditions.