Number portability is a telecommunication network function, which allows subscribers to switch services, service providers, or locations without changing their telephone numbers. Near-term number portability is typically implemented by existing telecommunication services such as remote call forwarding. Long-term number portability can be implemented under the advanced intelligent network (AIN) platform. This article focuses on the routing issues for number portability. We introduce the number portability issues and provide a tutorial on the AIN. We then show the AIN implementation for long-term number portability. Finally, a cache approach is proposed to speed up address transfer, which can effectively reduce the network overhead incurred by AIN query for number portability.

This article describes iSMS; a platform that integrates IP networks with the Short Message Service in mobile telephone systems, iSMS provides a generic gateway for creating and hosting wireless data services for mobile stations. Our approach does not require any modification to the mobile telephone system architecture. The iSMS system can be quickly developed and operated by a third party or end user without involvement of mobile equipment manufacturers and telecom operators. Based on the iSMS platform, we illustrate services such as e-mail delivery/forwarding, Web access (e.g., stock and train schedule query) and handset music services. The iSMS platform and the services have been implemented for GSM networks. With iSMS, users are able to use standard GSM handsets to access wireless Internet services, while other approaches like Wireless Application Protocol and SIM Toolkit services require function-enabled MSs.