USSD-request - a short combination of numbers that is dialed on the mobile phone and allows you to obtain any necessary information or perform some action.
USSD is an abbreviation of the EnglishUnstructured Supplementary Service Data. This is one of the services in the GSM-network, which allows subscribers to quickly interact with the service operator applications. Technology used for data transmission via the USSD-request has certain technical and functional similarities with SMS technology, however, has several differences.
Features USSD technology
USSD is a session-orienteda technique in which data transmission occurs within the established session. In this part of construction is very similar to the USSD service interactive systems based IVR - Interactive Voice Response. The main difference from the USSD technology is absence of IVR voice connection between the subscriber and the service.
The original purpose of the USSD-respect, it wasproviding the subscriber to the profile self-management of services in the HLR - database of subscriber information, as well as interact with the HLR integrated services. Over time, the technology function has been added to external applications, then USSD-communication has become ideally suited for working with information services that have an interactive structure - Service inquiries, banking services, customer care services and others.
The principle of USSD-service
Explain the USSD-service work can be on a specificExample. For example, the subscriber needs to find out the condition of settlements with its operators. Service «Balance Test» USSD system has assigned the short number 100. In order to use this service, the customer must dial the mobile * 100 # and press the call key.
The symbols * and # at the beginning and end of the numberused for mobile operator knew that is not a normal call and request services USSD-service. In processing the request is transmitted corresponding USSD-application. Next USSD-application interacts with the database billing system data, receives the information and sends it to a USSD-package on a mobile phone subscriber. The contents of this package is displayed in text form on the screen.
USSD-requests The system allows you to receivethe lowest possible latency between the user query and the answer is an operator that can not be achieved when using applications that run on the basis of SMS. However, USSD-technology is not a competitor SMS. These two services are complementary. They allow mobile operators to combine both methods, giving customers the opportunity to choose the most convenient one.