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## Resource: wix-realtime-backend

## Namespace: permissions-router

## Article: Introduction

## Article Link: https://dev.wix.com/docs/velo/velo-only-apis/wix-realtime-backend/permissions-router/introduction.md

## Article Content:

# Introduction
Use the permissions router to define the permissions you want to grant to subscribers
 on channels or channel resources. You can set permissions on the channel and channel
 resource level. If you do not define permissions for a particular channel resource,
 that resource inherits the permissions of its parent channel.

 Typically you use the permissions router in the **realtime-permissions.js** file in
 your site's backend to:

 + Set default permissions for all channels and channel resources where no explicit
   permissions are defined.
 + Add permissions logic for specific channels or channel resources.
 + Check the permissions for a specific subscriber on a specific channel.

 > **Note:** Although it is recommended, you do not need to use the permissions router to set permissions. You can also define all your permissions logic in the [`realtime_check_permission()`](#realtime_check_permission) function.