There is no license for RDD. The service is complimentary with a Ruckus Support Contract.
Ruckus Diagnostic Dashboard (RDD) is a lightweight tool that helps automate the troubleshooting and support process. RDD provides a single pane of glass view for Ruckus Support. Here you will find all the latest information on RDD releases, interact with the Product Management, and Support teams.
For more information check out the RDD Value Proposition on the Ruckus Support Site https://support.ruckuswireless.com/Ruckus_Diagnostic_Dashboard