An SMS gateway allows an application to send and receive Short Message Service (SMS) messages to and from a telecommunications network. The vast majority of messages are routed by an SMS gateway into the mobile phone networks.
An SMS gateway typically sits between the end user application that needs to send/receive SMS and a mobile network's Short Message Service Centrer (SMSC). Such gateways provide their customers with a choice of APIs, including HTTP, SMTP, Short Message Peer-to-Peer and Web Services. Providers of SMS gateway services include SMS aggregators and mobile operators.
In order to send/receive messages with mobile subscribers, an SMS gateway connects with (i) mobile network SMSCs and/or (ii) other SMS gateways. It is therefore possible that an SMS gateway has a combination of connections with mobile network SMSCs and connections with other SMS gateways in order to provide its services. However, there is the increasing potential for delivery problems with SMS the greater the number of SMS gateways in the delivery chain. The short message will eventually pass into an SMSC that then performs the delivery attempts to the destination mobile.