# User-based Network IDs

### Managing compartments in the mediarithmics platform

**User-based Network IDs** refer to **Compartments** because each user network ID is assigned a compartment where its identifiers are stored.

#### **How to activate a compartment on a datamart**

Here are general steps to follow in order to activate a Compartment on a specific datamart:

* **If you have a single datamart**, the Compartment is automatically activated.
* **If you have multiple datamarts**, you must activate it on every datamart
  1. Head to **Navigator > Settings > Datamart > Compartments.**
  2. Select your Compartment.
  3. Click to the **More** button to open the menu.
  4. Choose **Edit linked datamarts.**
  5. Select the datamart where you want to activate the Compartment.

#### Activate IDs across your organisations:

For community-created user IDs, activate them across organizations by selecting Enable Compartment in the Shared User Account Compartments Enabled section.