A method performed by a Software Defined Networking Open Flow, SDN-OF, capable network controller, the method comprising: • determining (S 401) a subset of network nodes among a plurality of network nodes of an Internet Protocol, IP, network as network nodes on which SDN-OF functionality is to be enabled, wherein after the enabling a hybrid network is provided, the hybrid network comprising IP network nodes and network nodes with SDN-OF functionality, wherein the network nodes of the hybrid network are communicatively coupled by a plurality of links, wherein the determining the subset of network nodes comprises: ∘ determining a minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled; and ∘ determining the locations of the minimum number of IP nodes in the IP network to be enabled with the SDN-OF functionality, wherein the determining the minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled with SDN-OF functionality comprises: ▪ determining, for each link of the plurality of links that includes at least one network node that is not enabled with SDN-OF functionality, a designated network node enabled with SDN-OF functionality for the at least one network node of the plurality of network nodes that is not enabled with SDN-OF functionality; and ▪ determining, for every network node enabled with SDN-OF functionality, at least one intermediate network node that allows rerouted packets to reach corresponding destinations without looping back to a failed link or failed network node; • receiving traffic data from the network nodes of the hybrid network by using a communication protocol, wherein the hybrid network contains those IP nodes of the IP network, which are not part of the subset of network nodes, and contains those network nodes constituting the subset of network nodes on which the SDN-OF functionality is enabled, • computing (S 403) traffic routing configurations based on the received traffic data; and • distributing (S 405) the traffic routing configurations to the subset of network nodes. • determining (S 401) a subset of network nodes among a plurality of network nodes of an Internet Protocol, IP, network as network nodes on which SDN-OF functionality is to be enabled, wherein after the enabling a hybrid network is provided, the hybrid network comprising IP network nodes and network nodes with SDN-OF functionality, wherein the network nodes of the hybrid network are communicatively coupled by a plurality of links, wherein the determining the subset of network nodes comprises: ∘ determining a minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled; and ∘ determining the locations of the minimum number of IP nodes in the IP network to be enabled with the SDN-OF functionality, wherein the determining the minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled with SDN-OF functionality comprises: ▪ determining, for each link of the plurality of links that includes at least one network node that is not enabled with SDN-OF functionality, a designated network node enabled with SDN-OF functionality for the at least one network node of the plurality of network nodes that is not enabled with SDN-OF functionality; and ▪ determining, for every network node enabled with SDN-OF functionality, at least one intermediate network node that allows rerouted packets to reach corresponding destinations without looping back to a failed link or failed network node; ∘ determining a minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled; and ∘ determining the locations of the minimum number of IP nodes in the IP network to be enabled with the SDN-OF functionality, wherein the determining the minimum number of IP nodes of the IP network on which the SDN-OF functionality is to be enabled with SDN-OF functionality comprises: ▪ determining, for each link of the plurality of links that includes at least one network node that is not enabled with SDN-OF functionality, a designated network node enabled with SDN-OF functionality for the at least one network node of the plurality of network nodes that is not enabled with SDN-OF functionality; and ▪ determining, for every network node enabled with SDN-OF functionality, at least one intermediate network node that allows rerouted packets to reach corresponding destinations without looping back to a failed link or failed network node; ▪ determining, for each link of the plurality of links that includes at least one network node that is not enabled with SDN-OF functionality, a designated network node enabled with SDN-OF functionality for the at least one network node of the plurality of network nodes that is not enabled with SDN-OF functionality; and ▪ determining, for every network node enabled with SDN-OF functionality, at least one intermediate network node that allows rerouted packets to reach corresponding destinations without looping back to a failed link or failed network node; • receiving traffic data from the network nodes of the hybrid network by using a communication protocol, wherein the hybrid network contains those IP nodes of the IP network, which are not part of the subset of network nodes, and contains those network nodes constituting the subset of network nodes on which the SDN-OF functionality is enabled, • computing (S 403) traffic routing configurations based on the received traffic data; and • distributing (S 405) the traffic routing configurations to the subset of network nodes.