# JAAS > JAAS is an enterprise layer on top of Juju that provides centralized controller management, OIDC authentication, and ReBAC authorization. 2026 CC-BY-SA, Canonical Group Ltd ## Pages in this subsection - [Cloud](https://documentation.ubuntu.com/jaas/latest/reference/cloud.md): Complete reference for JAAS cloud entities including cloud tags, permissions like administrator and can_addmodel, and access control. ## Optional - [Top-level llms.txt](https://documentation.ubuntu.com/jaas/latest/llms.txt): Complete documentation index.