---
title: Define Access Control Lists (Rules and Permissions)
slug: uns/define-access-control-lists
description: Learn how to define access-control lists in Litmus UNS. 
docTags: 
createdAt: 2023-12-13T13:43:29.274Z
---

After [Adding a user](docId\:RjeFZNOr7o0fQ8DLlvB5L), you will need to define rules to define permissions for it. By default, the user will be able to connect to Litmus UNS through an MQTT client, but will not have any *Subscribe *or *Publish *permissions. You have two options for accessing rules and permissions. 

# Option 1: Define Rules in Unified Namespace Settings (UNS)

You can also define rules and permissions within the UNS settings for Litmus UNS. 

**To define rules in UNS Settings:**

1. In the navigation menu, click **Unified Namespace (UNS)**. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/cZ0WkVk7voM9R8D7ASiz7_unsmenuitem.png "UNS menu item")
2. Click **Add permission**. 
   The *Add permission* dialog displays. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/8Sun7atwGRqUdV0nsFRqw_addpermission.png "Add permission icon")
3. Configure the parameters for the rule.
   - **Topic**: Enter the topic name the defined user will get access to. To define a wildcard so the user can access all topics, enter **#**. 
   - **Account**: Select the appropriate user for the rule. 
   - **Permission**: Select a permission: Deny, Publish, Publish & Subscribe, or Subscribe. 
4. When done configuring the rule, click **Save**. 

# Option 2: Define Rules in User Settings

You can access rules for individual users in the user's settings. 

**To define permissions for a user:**

1. From the navigation menu, click **Security**. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/eFqY5jmBbj8Gb8T8VTSqi_securitymenuitem2.png "Security menu item")
2. Click the account name you want to add the rule to. 
   The *Account Details* display. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/lUFhtc2QzMzrW_24uRK4r_accountname.png "Account name")
3. In the *Rules *section, click the **Add **icon. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/nlwvjkgKKokXZ-Gl3GS1L_addrule.png "Add rule icon")
4. Enter the topic name the user will get access to. To define a wildcard so the user can access all topics, enter **#**. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/x_y_5T8NDdAuBxxQEinf6_topicfield.png "Topic definition field")
5. Define a permission for the user: Deny, Publish, Publish & Subscribe, or Subscribe. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/MsOu8bnUUDiCWZP1bXyEi_permissionfield.png "Permission field")
6. When done defining the rule, click the **Save **icon. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/ziAa210RPuIOsxXzF45Jm_definedrule.png "Save rule icon")

The rule is added for the user. You can edit or delete the rule under *Actions*. 

![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/KLWjG0Svb8kb-ix2QKgm5_image.png "Edit and delete rule options")