FIELD: communications engineering. SUBSTANCE: method involves stages of checking for alternative channel between two terminal nodes of communication line in case of trouble in communication line; if alternative channel is available, communication line is placed in failure condition considering that there is channel that can replace it; in absence of alternative channel, communication line is placed in non- confirmed failure condition due to checking control unit considering that network is divided into two separate parts. EFFECT: facilitated computation of communication channel identifying function to detect open or closed circuit between network and its parts. 2 cl, 3 dwg
