Definition of USSD

Unstructured Supplementary Service Data is used for GSM communication

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USSD or Unstructured Supplementary Service Data is a protocol used by GSM based mobile phones to communicate with the network operator’s computer.

How It's Used

USSD is widely used for a variety of purposes, such as prepaid callback service, location-based content service, WAP browsing and so on. Additionally, it is also used as a part of configuring the user’s handheld on the network.

Unlike the SMS, the USSD establishes a connection in real-time between the parties involved, thereby enabling a two-way communication of information as long as the connection remains open.

Example

An example of USSD in action would be an application on your phone that allows you to check your account balance and add more to it.