USSD-request is a short combination of numbers, which is dialed on the mobile phone and allows you to get any necessary information or perform some action.
USSD is an abbreviation of EnglishUnstructured Supplementary Service Data. This is one of the services in GSM-networks, which allows subscribers to quickly interact with the service applications of the operator. The technology involved in data transfer through USSD-requests has certain technical and functional similarities with SMS technology, but it has a number of differences.
Features of USSD technology
USSD is a session-orientedTechnology in which data transmission occurs within the established session. In this part of the build, the USSD is very similar to the interactive IVR service Interactive Voice Response. The main difference between the USSD technology and the IVR is the absence of a voice connection between the subscriber and the service.
The original purpose of the USSD connection wasProviding the subscriber the opportunity to independently manage the service profile in the HLR-database with information about subscribers, and also to interact with the services built in HLR. Over time, the function of connecting external applications was added to the technology, after which the USSD-communication was ideally suited for working with information services, which have a dialog structure - help desk, banking services, customer service and others.
How does the USSD service work?
Explain how the USSD service works on a specificExample. For example, a subscriber needs to find out the status of mutual settlements with his operators. The USSD system assigned a short number 100 to the "Balance Check" service. In order to use this service, the client should dial * 100 # on his mobile phone and press the call key.
Symbols * and # at the beginning and end of the numberAre used to ensure that the mobile operator understands that there is not a normal call, but a request for services of the USSD service. During processing, the request is passed to the appropriate USSD application. Further, the USSD application interacts with the billing system database, receives the necessary information and sends it as a USSD packet to the subscriber's mobile phone. The content of this package is displayed as text on the device screen.
The system of USSD-requests allows you to receiveThe minimum possible delay between the subscriber's request and the operator's response to it, which can not be achieved with the use of applications based on SMS. However, USSD technology is not a competitor to SMS. These two services are complementary. They allow mobile operators to combine both methods, giving subscribers the opportunity to choose the most convenient of them.