As depicted in the architecture overview in Fig. 5, this module contains a ServerNode, a JobScheduler and a UserManager. The ServerNode acts as the control center of the whole security framework, where the Jetty server is launched to run the HTTP service to provide the log in/out, job submission and other Web-based user interfaces for using the G-Hadoop resources. Besides the Jetty server, the ServerNode also runs other important components to support the requirements of the security framework.