Methods and network nodes are described. A network node receives an attach request message from a wireless transmit/receive unit (WTRU) via a cellular radio access network (RAN). The attach request message includes a mobile station (MS) radio access capability information element (IE), and the MS radio access capability IE includes a field that indicates whether the WTRU is capable of receiving services from a core network via a non-cellular wireless access network. The network node provides services from the core network to the WTRU.