This study proposes a method to handle unrecoverable data using a formula called Bézier curve. The proposed method suggests the possibility to approximate the damaged data, which have been processed by the error correction scheme. The proposed method works on the real-time distributed system which retransmission is considered as unsuitable solution to manage the overall networked system. By using the Bézier curve, the transmitted unrecoverable data are reconstructed again by using the functional approximation. This method provides a smoothing effect on damaged data that usually are normalised on real-time transmission of PROFIBUS. Three differences Bézier curve methods are compared in PROFIBUS data, four-points (FP) method, two-points two-degrees method and four-degrees (FD) method. Simulation results show that all three Bézier curve methods can approximate data in PROFIBUS. FD has higher computation complexity compared with others. However, FD compensates with its data size which is only half of FP method.