**To register a self signed device certificate** The following ``register-certificate`` example registers the ``deviceCert.pem`` device certificate signed by the ``rootCA.pem`` CA certificate. The CA certificate must be registered before you use it to register a self-signed device certificate. The self-signed certificate must be signed by the same CA certificate you pass to this command. :: aws iot register-certificate \ --certificate-pem file://deviceCert.pem \ --ca-certificate-pem file://rootCA.pem Output:: { "certificateArn": "arn:aws:iot:us-west-2:123456789012:cert/488b6a7f2acdeb00a77384e63c4e40b18b1b3caaae57b7272ba44c45e3448142", "certificateId": "488b6a7f2acdeb00a77384e63c4e40b18b1b3caaae57b7272ba44c45e3448142" } For more information, see `RegisterCertificate `__ in the *AWS IoT API Reference*.