Enabling roaming 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 to enhance cellular services. Nowadays, it is not surprising to see heterogeneous wireless networks coexisting on a daily basis i.e. UMTS, WiFi, and WiMAX. Unfortunately, technical issues and the lack of roaming agreements between network operators prevent interoperability. One of the goals of next generation wireless networks is to enable service mobility between heterogeneous wireless networks, thus we present in this article a SIP-based roaming architecture to enable service mobility in heterogeneous multi-operator wireless networks. Our objective is to establish mutual trust between cellular network operators and unlicensed wireless networks through a efficient SLA monitoring and enforcement and brokerbased access control. All this, with minimal changes in current wireless network architectures.