The invention relates to a method for operating a switching node of a communications network, wherein the communications network comprises a layered architectural environment and a non-layered architectural environment. The switching node provides processing capabilities for the processing of communications services both within the layered and the non-layered architectural environment The method comprises the steps of receiving a communication service request, determining according to at least one predetermined rule as an operation mode, whether the switching node is going to act for a processing of the requested communication service as a switching node of the layered architectural environment or as a switching node of the non-layered architectural environment, and processing the requested communications service in accordance with the determined operation mode of the switching node. The invention relates further to a corresponding network node, communications system and computer program.