Various cellular, and cellular-like systems have been developed and deployed that provide mobile, and other wireless, communication services. Wireless local area networks (WLANs) are exemplary of such cellular-like communication systems. A WLAN is typically an IP (Internet Protocol)-capable network implemented, e.g., pursuant to Wi-max, 802.11a, b, g, n, GERAN (Generic Radio Access Network), UTRAN (Universal Terrestrial Radio Access Network), LTE (Long Term Evolution), or any of various other network-technology schemes. WLAN systems are generally deployed over relatively smaller areas than the areas over which a cellular, i.e., a PLMN (Public Land Mobile Network) is typically deployed but other WLAN technologies such as but not limited to Wi-max are now providing coverage comparable to that of a PLMN. A WLAN is deployed, for instance, to encompass a business, or other, enterprise. Sometimes, a WLAN is operated by an operator that also operates a PLMN.
Interworking between WLAN systems and PLMN systems provide for seamless communication operations using a mobile station operable in both of the network systems. As communication by way of a WLAN system is generally less expensive than communications by way of a PLMN system, if communications by way of the WLAN system are available, communications by way of the WLAN system are generally preferred.
A mobile station that operates in a PLMN system, is associated with a home network, i.e., an HPLMN (Home Public Planned Mobile Network). Subscription is typically made for specific services, herein referred to as HPLMN services, permitted of the mobile station pursuant to its service subscription. When the mobile station is positioned to be in direct communication connectivity at the HPLMN, such services are made available to the mobile station upon its authentication at the HPLMN. When, however, the mobile station roams beyond the coverage area of the HPLMN, or otherwise does not communicate directly with the HPLMN, the mobile station accesses the HPLMN by way of another network, such as a WLAN. An authentication mechanism, carried out by way of the other network, for access by the mobile station to the HPLMN services is sometimes required.
Recent attention has been directed towards such a mechanism. For instance, a series of documents of the technical specification, TS 24.234 define two mechanisms by which to permit a wireless device, a UE (User Equipment), to access HPLMN services. One mechanism pertains to the use of IEEE 802.1x authentication. And, a second mechanism is by way of a non-802.1x authentication-capable WLAN. In the second mechanism, the wireless device tunnels directly to a HPLMN network node e.g. a PDG (Packet Data Gateway) etc. The availability of networks by way of which the wireless device is able to attempt access to the HPLMN services depends upon the location at which the wireless device is positioned.
While the aforementioned technical standard defines two mechanisms by which the wireless device can access an HPLMN system, the existing technical specification, to date, has not defined various aspects of the mechanisms. For instance, the technical specification fails fully to define working of the mechanisms when combined together.