Disclosed herein are systems, computer-implemented methods, and computer-readable media for authentication using a shared table. The system also includes communication links between adjacent nodes, whereby the nodes form a network. The steps of descending, ascending, and horizontally moving the machining tool are performed repeatedly to form the dot-like reflection portions. The cylinder crankcase includes a belt driven valve train and crank arm that includes a pocket containing a crank gear attached to the crankshaft for driving the belt.