According to the invention a synchronous hierarchic network system and a method of transmitting data are disclosed using at least a path segment between a first network element (A) and at least a second network element (F) on which a tandem connection monitoring (TC) method is established for monitoring information over said path segment, and means for minimizing the signal interruption due to a loss of multiframe alignment subsequent to an interruption, distortion or switching operation of the signal transmission path. |