A method for a handover of a mobile node from a non-3GPP to a 3GPP network, and of a mobile node, which is located in a non-3GPP/3GPP network. The handover is improved by discovering an appropriate MME and registering the mobile node at the discovered mobility management entity (MME), in advance. This includes to first determine the location of the mobile node in the non-3GPP network, so as to be able to detect an MME in the vicinity of the mobile node's location. The 3GPP contexts are then transmitted to the new MME before the handover is performed. Moreover, the Serving-Gateway in the 3GPP network is changed before performing a handover, thereby accelerating the handover. When a handover gets likely, the mobile node's location is determined and a new Serving-Gateway is selected. The data path is changed to go via the new Serving-Gateway.