The present disclosure provides a bootstrapping server, a network application function (NAF), a system and methods for establishing secure communication between a machine to machine (M2M) device and a NAF. A method for establishing secure communication between the NAF and M2M device comprises receiving a first data object, tunneling the first data object to the M2M device, via an interface between the NAF and the M2M device, for enabling the M2M device to derive first information to establish said secure communication, receiving a second data object and deriving second information for use in establishing said secure communication with the M2M device.