> For the complete documentation index, see [llms.txt](https://developer.ecall-messaging.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.ecall-messaging.com/api-references/smpp.md).

# SMPP

## SMPP

Use the eCall SMPP interface to send SMS messages and receive callbacks.

### At a glance

* Host: `smpp.ecall.ch`
* Port: `2776`
* Transport: **TLS 1.2** or **TLS 1.3**
* Protocol: **SMPP v3.4**

### Navigate this section

* [Getting started](/api-references/smpp/getting-started.md) — prerequisites, protocol version, and connection details
* [Session management](/api-references/smpp/session-management.md) — supported commands, bind flow, and keep-alive behavior
* [Sending SMS](/api-references/smpp/sending-sms.md) — `submit_sm` and supported parameter values
* [Receiving messages](/api-references/smpp/receiving-messages.md) — delivery receipts and inbound SMS
* [Error codes](/api-references/smpp/error-codes.md) — custom eCall SMPP errors
* [Code examples](/api-references/smpp/code-examples.md) — Python, Java, and C# examples

### Core features

* Send single-part and multi-part SMS messages. 
* Receive delivery receipts.
* Forward inbound SMS to your client.

{% hint style="info" %}
Use `bind_transceiver` for most integrations.
{% endhint %}


---

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