System, the method and apparatus of non-3 gpp net access 3GPP core net

The invention discloses system, the method and apparatus of a kind of non-3 gpp net access 3GPP core net, wherein, described method comprises: request is set up in the tunnel that IAD receiving terminal sends, and described tunnel is set up in request and carried public data network PDN connection type; Described IAD sends the request of PDN connection establishment to 3GPP equipment of the core network, and request is set up PDN with described 3GPP core net and is connected, and carries described PDN connection type in the request of described PDN connection establishment; Described IAD receives described 3GPP equipment of the core network after the success of PDN connection establishment, is the network address of described terminal distribution according to described PDN connection type; The described network address is sent to described terminal by described IAD.