Authentication, authorization, and accounting (AAA) are the three major pillars of access control. Authentication identifies the user, authorization identifies the roles of the user, and accounting ensures that the user actions are performed within the usage limits (such as throttling). AAA, as they are collectively known, are crucial for networks for proper functioning and security. Hence network projects consider AAA as a crucial factor in their network architecture—remarkably the OpenDaylight's AAA project is considered to be a core project in the SDN controller ecosystem. In this chapter, we will look into the AAA options for networking, and how to configure AAA with Python for the networks. We start the chapter with simpler recipes before going into more complex ones.