SMS (short messaging service) is a method to send short messages from one cell phone to another. When SMS services are used, the mobile terminal sends an short message to certain number (usually a short specialized number) which points to specific SMS center responsible for that number. This SMS center then sends the message onward to specified receiver in intranet or internet, using an SMS center specific protocol. For example, a Nokia SMS center uses CIMD protocol.

Different SMS center uses different protocol, so SMS gateway is used to handle connections with SMS centers and to relay them onward in a unified form. SMS gateway is a system or service that enables SMS transit, transforming messages to mobile network traffic from other media, or vice versa, and enables transmission or receipt of SMS messages with or without the use of a mobile phone.

The UNICOM^® Digital Transformation Toolkit (UDTT™) SMS Handler is a component to handle the connectivity to different SMS gateways, and parsing the SMS commands. It aligns with the UDTT channel framework, which makes it easy to integrate the SMS channel with other channels and leverage other functions of UDTT, such as operation step, channel policy, backend invoker, and Web2.0 frameworks. The UDTT SMS Handler has following features: