# Cloud Protocols

### Introduction

The parts of [YuDash IIoT Stack](/device-to-cloud-api/yudash-iiot-stack.md) covered in this section are shown below.

<figure><img src="/files/RT4zjvLIaGhC4RCf87It" alt=""><figcaption></figcaption></figure>

### Selection of Cloud Protocol in LYNX and YuDash IoT devices

By default, YuDash LYNX is configured to connect to YuDash cloud. This is subject to tje purchase of YuDash cloud or YuReCon subscription. In such cases, "Use YuDash Cloud " is check marked. In this case, all custom cloud settings are ignored. LYNX will attempt to connect pre-configured device credentials to YuDash Cloud. For using external cloud (or on-premise) server, the applicable cloud protocol has been selected.&#x20;

**Following are the steps to select generic cloud protocol:**

* Uncheck "User YuDash Cloud". This will disable use of YuDash cloud.&#x20;
* Select the **Custom Cloud** protocol:  MQTT, HTTP or FTP

<figure><img src="/files/VbLH8jlYNRr4Kb1D3H4y" alt=""><figcaption></figcaption></figure>

The offline mode is used when no cloud server is applicable. This is applicable for (a)  YuDash IoT device as local logger, (b) on-premise remote display units (c) debugging and setup purpose with field instruments for Modbus.

**Custom Cloud Settings**

Details of cloud settings are filled in the sub-section below:

<figure><img src="/files/89cyNcaxxupuxgiWx44Z" alt=""><figcaption></figcaption></figure>


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