SMPP Gateway

A modern, open-source Java library implementing the SMPP 3.4 protocol for high-performance SMS messaging. It serves as the actively maintained replacement for the abandoned Cloudhopper SMPP library, which was last updated in 2015.

For nearly a decade, Cloudhopper was the de facto standard for SMPP in Java. However, its abandonment left the Java ecosystem without a modern, maintained SMPP library. As SMS continues to be critical infrastructure for two-factor authentication, notifications, and A2P messaging, developers needed a contemporary alternative built with modern Java practices.

Key Features:

• Java 21 LTS – Built from the ground up with virtual threads, records, sealed classes, and pattern matching for cleaner, more maintainable code. • Immutable PDUs – All Protocol Data Units are thread-safe by design using immutable records with fluent builders, eliminating concurrency bugs common in the original Cloudhopper implementation. • High-Performance Netty Transport – Zero-copy buffer handling for maximum throughput, capable of handling thousands of messages per second. • Complete SMPP 3.4 Implementation – Full support for all PDU types including SubmitSm, DeliverSm, DataSm, QuerySm, and all bind types (Transmitter, Receiver, Transceiver). • Production-Ready Features – Automatic reconnection with configurable backoff, request windowing, TLS/SSL support, and comprehensive error handling. • Clean, Modern API – Intuitive fluent builders and well-documented interfaces make integration straightforward.