Research on international roaming between heterogeneous networks

The networks that provide services with different capabilities are known as heterogeneous networks. There are many problems of prepaid international roaming between heterogeneous networks. Through research and analysis of existing problems and key issues including service identification and trigger, service control, on-line charging and voice navigation, a new method based on roaming agent is proposed to solve the problems without major modifications to the legacy networks. The roaming agent, by providing signaling and voice prompts conversion between different prepaid service systems, is able to provide interoperability between heterogeneous networks. And the method has successfully passed verification test for bilateral prepaid roaming between mobile networks of Mainland China and Hong Kong.