Cloud Authentication depends on the TIBCO Connected Intelligence Cloud (CIC) to provide the authentication service. You may test this by creating a token in CIC, and passing that token as the Bearer token in the Authorization HTTP Header when interacting with a deployed stream. Tokens may be generated in the CIC web interface under Settings > OAuth access tokens.
Proper configuration of the URL and user credentials in Spotfire for Cloud Authentication depends on whether your Spotfire server is managed on-premise or in the TIBCO Cloud. Cloud Spotfire 11 will display all the running streams and you may select one of those. The URL and authentication is transparently handled. On-premise Spotfire does not support TIBCO Cloud Authentication, so you would still need to use basic authentication in this case (and later upgrade from on-premise Spotfire to Cloud Spotfire).