The inventive method provides that the failure of a segment, which connects two autonomous systems, is communicated as a segment failure to affected autonomous systems. The autonomous systems informed of the segment failure then deactivate inter-domain routes containing the down segment. After restoring the segment, the routes containing the segment can be reactivated after the propagation of a corresponding message. The method can use conventional protocols, particularly the Border Gateway Protocol, by treating the down segment as a route that is made recognizable as a segment by means of a PATH ATTRIBUTE. In contrast to the conventional procedure within the framework of the Border Gateway Protocol, routes that can no longer be used do not need to be individually communicated. An efficient propagation of the information concerning the fault and an improved convergence of the routing information of the autonomous system, said routing information being changed thereupon, is thus achieved.