Dependability verification of architecture changed automatic train control system

In automatic train control (ATC) railway signalling equipment, equipment cost is minimised by achieving energy saving and space reduction changes. The verification of dependability with architecture change was tried without worsening high reliability and safety. The following were carried out: the effect of the resources communization; evaluation of the reliability; and evaluation of the safety on the N+1 and N+2 systems. Compared with the same size of the apparatus, the same efficiency was obtained.