Short Message Peer to Peer (SMPP) protocol is an open, industry standard protocol designed to provide a flexible data communications interface for transfer of short message data between a SMS peer entities such as short message service centers and/or External Short Messaging Entities. It is often used to allow third parties (e.g. value-added service providers like news organizations) to submit messages, often in bulk. It sends and receives medium-to-high volumes of SMS texts. The SMPP uses the client-server model of operation. Message exchange may be synchronous, where each peer waits for a response for each packets being sent, or asynchronous, where multiple requests can be issued without waiting and acknowledged in a skew order by the other peer.