Short message service centre

When a user sends a text message (SMS message) to another user, the phone actually sends the message to the SMSC. The SMSC stores the message and then delivers it to the destination user when they are available. This is a store and forward operation. The SMSC usually has a configurable time limit for how long it will store the message, and the user can usually specify a shorter time limit if they want.

Two companies who make many of the SMSCs in use in the GSM world are Logica and CMG - or rather just one company, LogicaCMG, as these two merged on 1st January 2003.

For bulk transmission and reception of SMS messages, SMSCs have conventional, fixed, network interfaces as well as mobile network interfaces. A number of protocols have been defined to support this sort of wire-line access. SMPP is the most commonly used of these protocols.