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https://cacerts.digicert.com/DigiCertGlobalRootCA.crt.pem
To use TLS transport, devices must verify ClearBlade IoT Core server certificates to ensure they're communicating with ClearBlade IoT Core rather than an impersonator. The following certificate packages support verification:
The complete Google root CA certification package (128 KB) for the regional MQTT URLs.
Caution: Google services' certificates can be issued by any of the Certificate Authority from this regularly updated list https://pki.goog/roots.pem. Applications connecting to Google services should trust all the Certificate Authorities from that list.
This package establishes the chain of trust to communicate with Google products and services, including ClearBlade IoT Core.
Devices with the complete root CA certification package communicate directly with the MQTT server.
This package is regularly updated.
Google's minimal root CA set (<1 KB) for
mqtt.2030.ltsapis.goog. The minimal root CA set includes a primary and backup certificate.This set is for devices with memory constraints, like microcontrollers, and establishes the chain of trust to communicate with ClearBlade IoT Core only.
Devices with the minimal root CA set communicate with the ClearBlade IoT Core via long-term support domains.
This set is fixed through 2030 (the primary and backup certificates won't change). For added security, Google Trust Services may switch between the primary and backup certificates at any time without notice.
After downloading Google root CA certificates to your device, you can configure an MQTT client to authenticate the device, connect to the MQTT server, and communicate over the MQTT bridge.
Configuring MQTT clients
MQTT clients authenticate devices by connecting to the MQTT bridge. To configure an MQTT client to authenticate a device:
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