SMPP — Short Message Peer-to-Peer
What is SMPP?
SMPP (Short Message Peer-to-Peer) is the industry-standard protocol messaging platforms and SMS aggregators use to exchange text messages with mobile carriers and gateways at scale, independent of any single vendor's API. It defines how a sending application binds to an SMPP server, submits messages, and receives delivery receipts and inbound messages over a persistent TCP connection, making it the backbone protocol underneath most SMS APIs even when a REST API sits in front of it.
More detail
SMPP connections are typically established as long-lived “binds” — transmitter, receiver, or transceiver — over TCP, rather than one HTTP request per message, which is why it can sustain very high sustained message throughput.
Most modern SMS APIs abstract SMPP away behind a REST or SDK interface, but carriers and aggregators still exchange traffic over SMPP under the hood, especially for high-volume enterprise routes.
Frequently asked
- Do I need to know SMPP to send SMS through an API?
- No. Most sending platforms expose a REST or SDK API and handle the underlying SMPP connections to carriers and aggregators internally, so integrators never touch the protocol directly.
- Why do carriers still use SMPP instead of a modern REST API?
- SMPP's persistent binds are built for sustained high-throughput message exchange, which suits the carrier-to-aggregator leg of the network better than short-lived HTTP requests, even though the application-facing API is usually REST.
See also
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