Large-scale text messaging programs require specialized software applications and services to handle message content and delivery scheduling, and message routing services to deliver messages via multiple cellular network carriers. SMS messaging application software supports scripting, scheduling, replying, and routing to an SMS gateway based on pre-configured algorithms, thus eliminating the need for an individual to send, monitor, and respond to each text. In this process, a sender uses an SMS messaging application to enter necessary data (message script, message sending schedule, messaging algorithms or logic, etc.) An SMS gateway (also known as SMS provider aggregator, or messaging server) encodes and routes text messages according to the specific requirements of the recipient’s wireless network operator or carrier. Network operators have SMS centers (SMSC) that forward the messages to the recipients’ mobile phones (see figure below). SMS responses are routed back through the same channels.
The system that will work best for you depends on the complexity of your intervention program, the programming and technical resources you have available, and the amount of customization your project will require. Many messaging application providers and SMS gateway providers provide both application and gateway services, in addition to professional services to assist with implementation and customization.
The most common platform options are either a simple, ready-to-go application or a customizable application with vendor support. It is also possible, although costly and requiring in-house programming expertise, to develop a system from the ground up. The Software and Hosting Options section offers more information about these options.