SMPP protocol specification

This page lists the SMPP specifications currently in use. The most widely used SMPP version is currently version 3.4. You may download the specifications in PDF format from this page. Ozeki SMS Gateway implements all of these protocol versions and is fully compliant with them.

For outgoing SMPP connections you can select which protocol version to use on the configuration form. For incoming SMPP connections, the protocol version is automatically determined by Ozeki SMS Gateway.

You can find a comparison chart of these SMPP protocol versions in our "Compare SMPP protocol versions" guide.

SMPP v3.3 specification

There are three versions of the SMPP protocol specification in use. The original public version of the specification is SMPP v3.3 and was released in 1997. SMPP systems using this version usually rely on two links an SMPP transmitter and an SMPP receiver. One link is used for sending the other is used for receiving SMS.

Download: SMPP v3.3 PDF (373Kb)

SMPP v3.4 specification

The original specification was updated to SMPP v3.4, the most important change in this version was the recommendation to use a single TCP/IP link to send and receive SMS messages instead of two links. This is called the SMPP transceiver connection. The word transceiver is a mix of the words "transmitter" and "receiver". Using a single link makes connection management much easier and more resource efficient on the server side. This protocol version is the most widely used version to date (year %2025).

Download: SMPP v3.4.pdf (1.13Mb)

SMPP v5 specification

SMPP v5 is currently the most up to date version of the SMPP specification. This version was released in 2003. The major change in this version was the shift to using Type-Length-Value (TLV) fields. The idea was great, but this version is not as widely adapted as SMPP version 3.4, as most SMPP systems were in operation before this protocol version was released and few providers decided to upgrade their system to work according to this standard, as the previous standard is fulfilling most of the needs.

Download: SMPP v5.pdf (1.01Mb)