Method for establishing or switching an optical transmission path in order to transmit an optical signal, wherein a telecommunications network comprises a plurality of optical network nodes (123, 123') and wherein the optical transmission path traverses at least two consecutive optical network nodes (123, 123') of a transmission segment, the at least two consecutive optical network nodes (123, 123') comprising at least a segment source optical node and at least a segment destination optical node, wherein, regarding the establishment or switching of the optical transmission path, a segment optical switching identifier information is transmitted by the segment source optical node and received by the segment destination optical node, wherein the segment optical switching identifier information is transmitted together with the optical signal, wherein the segment destination optical node comprises a probe optical branch (124', 125', 126') and at least a first output port (B') and at least a second output port (C'), wherein, in order to establish or to switch the optical transmission path through the optical network nodes (123, 123') of the telecommunications network, the method comprises the following steps: -- in a first step, the segment optical switching identifier information is detected and determined by the segment destination optical node and -- in a second step, the segment destination optical node is controlled such that - depending on the determined content of the segment optical switching identifier information - either the first output port (B') or the second output port (C') is selected regarding establishing or switching the optical transmission path of the optical signal, characterized in that the segment optical switching identifier information is able to be enriched, by a local node controller of the optical network node (123, 123'), by means of additional information in order to change a preconfigured route or path that is defined by a global source optical node. wherein, regarding the establishment or switching of the optical transmission path, a segment optical switching identifier information is transmitted by the segment source optical node and received by the segment destination optical node, wherein the segment optical switching identifier information is transmitted together with the optical signal, wherein the segment destination optical node comprises a probe optical branch (124', 125', 126') and at least a first output port (B') and at least a second output port (C'), wherein, in order to establish or to switch the optical transmission path through the optical network nodes (123, 123') of the telecommunications network, the method comprises the following steps: -- in a first step, the segment optical switching identifier information is detected and determined by the segment destination optical node and -- in a second step, the segment destination optical node is controlled such that - depending on the determined content of the segment optical switching identifier information - either the first output port (B') or the second output port (C') is selected regarding establishing or switching the optical transmission path of the optical signal, -- in a first step, the segment optical switching identifier information is detected and determined by the segment destination optical node and -- in a second step, the segment destination optical node is controlled such that - depending on the determined content of the segment optical switching identifier information - either the first output port (B') or the second output port (C') is selected regarding establishing or switching the optical transmission path of the optical signal, characterized in that the segment optical switching identifier information is able to be enriched, by a local node controller of the optical network node (123, 123'), by means of additional information in order to change a preconfigured route or path that is defined by a global source optical node.