Only documented APIs, authorised hardware interfaces and carrier-approved configurations are supported. A gateway stays Awaiting heartbeat until it reports in. Gateway agent gateways report through the signed protocol in docs/INTEGRATION.md; after registering, an administrator issues the agent secret on the server.
Credentials are never entered or shown in the browser. For a gateway agent, issue its signing secret on the server with php bin/gateway-secret.php GW-XXX-00; it is shown once there and stored encrypted.