In this paper, a mathematical derivation for the probability to interpret an erroneous pointer in the SDH network is carried out. The derivation is based on International Telecommunication Union Telecommunication standardization section (ITU-T) recommendations for both the steady state and at the beginning of new data. The poses and cones of the ITU-T recommended way are discussed. To validate the analytically derived equations, a simulation program for a communication channel utilizing the SDH technique is developed. The results of both the analytical derived equations and the simulation program are presented. The obtained results are very close to each other.