Yes. If your Surveillance Station runs in an isolated network without Internet connection, use Synology Surveillance Station Client or DS cam to manage device licenses offline.

Add/Delete licenses offline via Surveillance Station Client

1. Launch Surveillance Station Client in an environment with Internet connection.
2. In the login page, click in the lower right corner.
3. Go to the License Management tab, and click Manage License.
4. Click Add License/Delete License.
5. Read the Terms and Conditions, tick the checkbox to agree, and click Next.
6. Select a server from the list below, or click Add and fill the in the required information to add a new server. Click Next to continue.
7. Enter the license keys and click Next.
8. Check the information in the appearing window and click Finish.
9. Return to an environment where Surveillance Station Client can connect to your Surveillance Station server.
10. Sign in to Surveillance Station Client. The licenses will be added or deleted automatically.

Add/Delete licenses offline via DS cam

1. Launch DS cam in an environment with Internet connection.
2. In the login page, tap in the lower left corner.
3. Tap Offline License Validation.
4. Tap Manage License > Add License/Delete License.
5. Read the Terms and Conditions and tap Agree.
6. Select a server or tap > Add Server.
7. Enter the required information and tap Next to continue.
8. Enter the license keys and tap Confirm.
9. Return to an environment where DS cam can connect to your Surveillance Station server.
10. Sign in to DS cam. The licenses will be added or deleted automatically.