A method based on CID service to realize MWI function for VMS service

Voice mail service in China was unable to notify customers the new voice messages arrival in the past. ETSI message waiting indicator function is briefly introduced at first. Then the feasibility of using the legacy SS7 signaling and calling identity delivery service in Chinese fixed-line network to realize the MWI is analyzed. A new method based on CID service without changing the legacy fixed-line network is proposed and the key technologies of the advanced VMS system and terminal with built-in indicator lamp to realize the MWI are presented at last. The method is adopted by China Netcom in their VMS product and presumable having positive effects on the spreading of VMS service in China.