USSI-Gateway
USSI-Gateway (USSI-GW) provides the option to enable deployment of legacy USSD application towards VoLTE users. The business purpose for this is to secure service continuity for users migrating towards the VoLTE domain.
USSI-GW enables re-use of legacy USSD applications servers including the existing USSD applications, which means that the operator can further monetize investments done in USSD services while deploying VoLTE.
USSI-GW is an ISC capable IMS application server, with a north bound interface which is connecting to MAP based USSD signaling. In a nut shell: USSI-GW receives “USSD over IMS” messages, sent from a user terminal, converts it to USSD strings, which are passed on over the north bound MAP interface.. And vice versa.
The purpose of the USSI-GW is to interact between the user VoLTE terminal and the USSD applications in the circuit switched domain. This enables operators to fully re-use their existing USSD services, like balance inquiry, top up or information services, to their VoLTE subscribers.
USSI-GW is based on the Ericsson Composition Engine, Ericsson’s strategic platform for Next Generation IN Applications. The platform provides crucial functionality for carrier grade performance link redundancy, high scalability and high availability. State of the art and commonly accepted integration points ensure easy introduction and deployment of USSI-GW in the operator domain.
Reducing the threshold for migration
USSI-GW reduces the threshold for subscribers to migrate to the IMS / VoLTe domain as they will continue to enjoy the service levels that they are familiar with in the circuit switched domain.
Safeguards investments
USSI-GW safeguards and strengthens investments done the legacy USSD environment, re-using these services as an initial service offering for IMS / VoLTE users.
With the re-use of legacy IN services for use in the VoLTE domain, also impact on the BSS systems (like prepaid handling) related to these services can be avoided.