# Mappings

Mappings describe the mapping of data from one topic to another, i.e. the data flow between e.g. devices and processing rules.

See also: [Cybus::Mapping resource](https://docs.cybus.io/1-7-3/documentation/services/structure-of-commissioning-files/resources/cybus-mapping)

## Overview

<figure><img src="https://950196595-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FwTih5dM9HKbgRlnp5wVj%2Fuploads%2Fgit-blob-008c1e0790c902f4d77e0cc83b5a9f16cf062bd1%2Fmappings_overview.png?alt=media" alt=""><figcaption></figcaption></figure>

By clicking on one of the listed mappings you get redirected to the [Details View](#details-view) of the selected mapping.

## Details View

<figure><img src="https://950196595-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FwTih5dM9HKbgRlnp5wVj%2Fuploads%2Fgit-blob-55680bc7309012ffa68abb763db8242cab0e67e3%2Fmappings_details.png?alt=media" alt=""><figcaption></figcaption></figure>

The mapping has resources itself. In this case there are only Mappings.

<figure><img src="https://950196595-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FwTih5dM9HKbgRlnp5wVj%2Fuploads%2Fgit-blob-83b861387ebc042f57c517e8422b14e0cd61ae40%2Fmappings_details_open.png?alt=media" alt=""><figcaption></figcaption></figure>

See also: [Mappings in the service commissioning file](https://docs.cybus.io/1-7-3/documentation/services/structure-of-commissioning-files/resources/cybus-mapping)

{% hint style="warning" %}
MQTT shared subscriptions are disabled on the Mapping entries view for the smooth operation of other clients possibly subscribed to the same topics.
{% endhint %}

<figure><img src="https://950196595-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FwTih5dM9HKbgRlnp5wVj%2Fuploads%2Fgit-blob-73956274d8d78815e07a920a9a6dc1a79f98216c%2Fmappings_details_shared_subscriptions.png?alt=media" alt=""><figcaption></figcaption></figure>

### Mappings

These are the actual mappings from endpoint to topic, or vice versa, that have been specified.