Azure Communication Services supports the following authentication methods:
-
Access key authentication
-
Microsoft Entra ID authentication
Retrieve the Azure Communication Services endpoint
Use the ACS endpoint when configuring SMTP email settings or application integrations.
-
Open the Azure Communication Services resource.
-
On the Overview page, copy the Endpoint value.
Retrieve ACS access keys
Retrieve ACS access keys for authentication. You can use either the primary key or secondary key. Using the secondary key enables key rotation without service interruption.
-
Open the Azure Communication Services resource.
-
On the Overview page, click Manage keys.
-
Copy either the primary key or secondary key.
Note
Access key authentication is simpler to implement but requires key rotation management. For production environments, consider Microsoft Entra ID authentication for enhanced security.
Configure a Microsoft Entra ID application
Microsoft Entra ID authentication enables secure, application-based authentication for Azure Communication Services.
Create a Microsoft Entra application
-
In the Azure portal, open Microsoft Entra ID.
-
Go to App registrations.
-
Click New registration.
-
Enter a name for the application.
-
Click Register.

Create a client secret
-
Open the newly created application.
-
Go to Certificates & secrets.
-
Click New client secret.

-
Enter a description.
-
Select the required expiration period (configure a reminder for secret rotation before expiration).
-
Click Add.
-
Copy and securely store the generated secret value.
Caution
-
The client secret value is displayed only once. You must store it securely before leaving the page.
-
Plan secret rotation before the expiration date to prevent service disruption.
Assign permissions to the Microsoft Entra application
-
Open the Azure Communication Services resource.
-
Go to Access control (IAM).
-
Click Add > Add role assignment.

-
Select the Contributor role (or a custom role with equivalent permissions for least privilege access).
-
Click Next.
-
Click Select members.
-
Search for and select the Microsoft Entra application.
-
Click Review + assign.
Note
After assigning permissions, the Microsoft Entra application can authenticate to Azure Communication Services using the client secret. Use the Application (client) ID, Directory (tenant) ID, and client secret when configuring Commvault.