SIP Embedded Attribute Certificates For Service Mobility in Heterogeneous Multi-Operator Wireless Networks

Next generation wireless networks will take advantage of the popularity and the data rates offered by unlicensed wireless networks such as WiFi (Wireless Fidelity) or WiMAX (Worldwide Interoperability for Microwave Access) to enhance cellular services Le. UMTS (Universal Mobile Telecommunication System). Although currently exist approaches that provide service mobility, they rely on the assumption that cellular operators also own or manage the WiFi/WiMAX networks. Nevertheless, in spite of the business-related and technical differences of network operators/service providers we consider that service mobility between cellular and independent unlicensed wireless networks is feasible. In this article we present the SIP embedded Attribute Certificates to enable service mobility in heterogeneous multi- operator wireless networks.