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SMPP Introduction

Short Message Peer-to-Peer (SMPP) is an open, industry standard protocol designed to provide a flexible data communication interface for the transfer of short message data between External Short Messaging Entities (ESMEs), Routing Entities (REs) and Message Centres.
SMPP is often used to allow service providers to submit bulk SMS messages.

The SMPP server

Host: port: 2778

Bindings and Throughput

Whenever an SMPP account has been set up, you’ll receive the maximum amount of binds you’re allowed to set up. As well as a maximum throughput. In most cases, this value means 3 binds and 50 messages per second.
The WTC SMPP server supports only one connection via transceiver (TRX) or multiple connections via a transmitter (TX) with one connected receiver (RX) if it’s needed.

Username and Password

You can receive your personal username (system_id) and password by the WTC account manager or generate SMPP-password in account settings by yourself.


For SMPP connection WTC requires to whitelist your originating IP. In order to access, please send your username and originating IP to our Customer Support team a [email protected].

Supported PDUs

The WTC server supports the following list of PDU types:

PDU namecommand_id















Bind PDU

An SMPP bind_receiver, bind_transceiver or bind_transmitter PDU request has a fixed set of fields. Most fields are irrelevant to us. In fact, we only read the system_id, password, system_type and interface_version fields. The rest is ignored.

Field name – Description

system_id – The username

password – SMPP-password

system_typeIGNORED if you want to use default tariff or set tariff-x, where x is the code of tariff name





The WTC SMPP server supports SMPP protocol version 3.4 and 5.0 NOTE for SMPP 5.0. Whether the command SUBMIT_SM_RESP contains a status with an error code the length of PDU is 16 octets.


The values for the data_coding field are not solidly declared in the SMPP spec, so each SMPP server is more or less required to give its own definition.

Value – Encoding

0 – Default Alphabet (GSM 3.38), 7-bit characters;

1 – IA5/ASCII, 7-bit characters;

3 – ISO-8859-1 (LATIN1), 8-bit characters;

5 – Japanese (JIS), multi-byte characters;

6 – Cyrillic (ISO-8859-5), 8-bit characters;

7 – Latin/Hebrew (ISO-8859-8), 8-bit characters;

8 – Unicode (USC-2), 16-bit characters;

14 – Korean (KS C 5601), multi-byte characters.

For 7-bit character sets, a maximum of 160 characters can fit into one SMS message; for 8-bit character sets, the limit is 140 characters; for 16-bit character sets, the limit is 70 characters; for multi-byte character sets, the limit is between 70 and 140 characters, depending on which characters the text of the message was made up. (For multi-byte character sets, most characters are 16 bits; some of the more common characters are eight bits.)