Logica SMPP Library is set of classes for communication with SMSC using SMPP protocol. SMPP Java library implements version 3.4 of the SMPP protocol.
It has an simulator which is an application for near-to-live testing of your SMPP applications without need of access to real SMSC.
SMPP, or Short Message Peer to Peer, is messaging protocol for integration of applications with wireless mobile network messaging systems. With SMPP you can as an application developer send data to mobile devices or to the other applications over SMSC (Short Messasge Service Centre).