Architecture alternative for wireless data services: interworking with voiceband modem

The paper describes an architecture that provides wireless data users with the ability to communicate with the wireline data service. This architecture uses a stand-alone interworking function (IWF) that connects to radio port control units (RPCUs) through an intermediate network and connects to the remote service via a remote network. The paper focuses on the architecture that uses X.25 as the intermediate network and PSTN as the remote network to provide voiceband modem services. This solution is similar to an existing serving arrangement which allows ISDN users to interwork with voiceband modems. Call origination, call delivery and automatic link transfer (ALT) for wireless data calls are discussed. Other communication channels between the RPCU and IWF (in lieu of the X.25 connection proposed in the present paper) are possible and many concepts will extend to such alternate architectures