A system configured to support software-defined networking, SDN, is described. The system comprises: a management client entity (310); main processing device (220, 320) operably connected to the management client entity (310) and arranged to communicate with the management client entity (310) using a first SDN protocol; a target server (330) running on a constrained device (228, 329) operably connected to the main processing device (220, 320) and arranged to communicate with the main processing device (320) using a second SDN protocol (242) that is different to the first SDN protocol. The main processing device (220, 320) comprises a data store (370) configured to perform as an interface between the first SDN protocol and the second SDN protocol (242).