The GLU.USSD Menu Builder is a Value Added Service (VAS) that is licensed separately from the Integration Platform. It enables our clients to configure and maintain their own USSD Menu’s which are then run on a USSD Server that is pre-integrated with the GLU.Engine.
Phase 2 USSD
Phase 2 USSD (Unstructured Supplementary Service Data) is a mobile communication technology used for two-way interaction between a mobile phone user and a service provider. It is an upgrade from phase 1 USSD, which only supports one-way communication. In phase 2 USSD, the user can initiate a session with the service provider and receive a response, making it a more interactive and dynamic system.
Additionally, Phase 2 USSD also offers enhanced security features compared to Phase 1, such as the ability to encrypt data in transit. This makes it a suitable technology for sensitive applications, such as mobile banking.
Overall, Phase 2 USSD is a powerful tool for service providers looking to offer mobile-based services to their customers in areas with limited internet connectivity. It enables efficient and secure communication and can help drive customer engagement and satisfaction.
The interactive nature of USSD Phase 2 allows an application to present options to a subscriber in the form of menus. These menus and the logic within them are not stored on the phone.
The menus are formatted text lists of options separated by line feed characters. On a handset, the text renders as a menu. The user responds by entering a character that corresponds with their chosen selection.
USSD is not a menu on the handset, it is the channel or bearer that delivers the menu text and selections. Menus are independent of the handset as well as the SIM card. The server-side application being the GLU.Ware configured USSD Menu running on the GLU USSD Sever keeps track of where in the menu structure every subscriber is at all the time.
Menus served over USSD should not be confused with menus and applications served by STK (Sim Tool Kit). STK is a technology embedded on the SIM card where special applications can be accessed by subscribers. With STK, the handset receives instructions from the SIM card to perform functions.
USSD differs from the other short message bearer, SMS, in a number of significant ways. It is not a store-and-forward bearer like SMS, but a transparent session-based bearer ideal for transacting. Information is delivered and responses obtained in real-time. Simply put, USSD is similar to speaking to someone on a phone as SMS is sending a letter.
USSD is also not a point-to-point bearer such as SMS. One subscriber cannot send another text using USSD unless there is a special network application offering such an application.
GLU.USSD and GLU.Engine’s in Context
The context diagram below describes broadly the components involved in serving a USSD Menu user using GLU.Ware. The MNO side is standard typically across all MNO’s, once a USSD Session is invoked by a User, it is passed across the network until it reaches the MNO’s USSD Gateway. From there the Gateway will associated the USSD Shortcode that invoked the session with the IP address of the USSD Server API as configured in the GLU.Engine. The GLU.Engine package combines both the USSD Server component (which runs the USSD Menu as it has been configured in the GLU.Console) and the GLU Integration Engine. The GLU USSD Server is configured to expose an API to receive the inbound USSD Request from the USSD Gateway and once received and menu interactions are completed, the USSD Server is configured to pass the request payload down to the GLU Integration Engine to process the transaction.

GLU.USSD Config Elements
The Menu Builder is accessed via the ‘GLU.USSD’ tool on the main navigation as below.
The Menu Configuration Console comprises of two elements – ‘Configuration’ and ‘Menus’.

The Configuration elements are used to configure the Menu Builder to receive the USSD Payload an API interface that is pre-defined in the ‘Connectors’ tool; it is used to configure all the messages that should be returned via the USSD Channel depending on the outcome of the USSD menu interaction and it is used to configure the the standard screen settings such as Headers and codes for Main Menu, Next Menu and Previous Menu.
The Menus elements are used to configure one or more USSD Menu’s. In a scenario where for example you have Merchants and Customers using the same Shortcode, you may want to present a different USSD Menu to a Merchant vs. a Customer. GLU.Ware supports the provisioning of multiple different menu’s which can be rendered based on the Shortcode string submitted, a user selection or ‘behind the scenes’ mapping of the originating MSISDN against the user type (from a back-end call via the Integration Engine).