An apparatus having computer implemented media independent access functions, comprising: an independent authenticator, said independent authenticator to authenticate mobile devices attached between heterogeneous media; an interface to connect said independent authenticator to a plurality of heterogeneous access networks each of which supports a specific authenticator that corresponds to a specific serving media; and predefined media independent handover protocols and media independent handover identities based on the media independent functions on the computer, wherein said independent authenticator authenticates candidate access networks prior to the handover of the mobile devices from serving access networks to the candidate access networks each of which belonging to the plurality of heterogeneous access networks having the specific serving media, characterised in that after the prior to handover authentication is successfully performed by said independent authenticator, said independent authenticator is adapted to generating media specific keys for each of the mobile devices and making said media specific keys available to said specific authenticator such that the mobile devices can, using the available media specific keys, perform a media specific security association with said specific authenticator when switching to any of the plurality of heterogeneous access networks without requiring the mobile devices to perform a full authentication process and establish an IP connection with the independent authenticator to register with the independent authenticator after successfully establishing the media specific security association with the specific authenticator. an independent authenticator, said independent authenticator to authenticate mobile devices attached between heterogeneous media; an interface to connect said independent authenticator to a plurality of heterogeneous access networks each of which supports a specific authenticator that corresponds to a specific serving media; and predefined media independent handover protocols and media independent handover identities based on the media independent functions on the computer, wherein said independent authenticator authenticates candidate access networks prior to the handover of the mobile devices from serving access networks to the candidate access networks each of which belonging to the plurality of heterogeneous access networks having the specific serving media, characterised in that after the prior to handover authentication is successfully performed by said independent authenticator, said independent authenticator is adapted to generating media specific keys for each of the mobile devices and making said media specific keys available to said specific authenticator such that the mobile devices can, using the available media specific keys, perform a media specific security association with said specific authenticator when switching to any of the plurality of heterogeneous access networks without requiring the mobile devices to perform a full authentication process and establish an IP connection with the independent authenticator to register with the independent authenticator after successfully establishing the media specific security association with the specific authenticator.