Being authenticated by the master node, the user can now submit jobs to G-Hadoop. In the following, the master node accepts the job, initializes it, creates a user instance for it, and finally contacts the CA server to apply a proxy credential for the user instance. It is possible that the user instance already exists, meaning that the off-line execution is activated. In this case, the master node only shows the current status of the active jobs to the user, and no further operation is performed.