Networks (8) for setting up connections between nodes (1,2) via request messages (R1) and allocation messages (A1) are made more efficient by providing the request messages (R1) with indications for indicating the first node's capabilities with respect to different signalling procedures and by providing the allocation messages (A1) with instructions for instructing the first nodes (1) to use one of the signalling procedures. Only one round trip is needed. The indications comprise first preference values for the first signalling procedure (wavelength switching) and second preference values for the second signalling procedure (waveband switching). The instructions comprise signalling information and signalling procedure assignments. The second nodes (2) run label assignment algorithms for making the signalling procedure assignment in dependence of the preference values. The first nodes (1) derive further signalling information from the signalling information, which signalling information is related to the first signalling procedure and which further signalling information is related to the second signalling procedure.