> For the complete documentation index, see [llms.txt](https://docs.parallels.com/landing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.parallels.com/landing/ras-admin-guide/parallels-ras-21-administrators-guide/ras-multi-tenant-architecture/deploying-tenant-broker-and-tenants/user-authentication.md). # User authentication User authentication in the RAS multi-tenant architecture is performed by the RAS Connection Broker running in the Tenant Farm. The Connection Broker is selected randomly by a shared RAS Secure Gateway. If the Connection Broker is unavailable, then it's marked accordingly and no communication is conducted with it from the same shared gateway for a period of time. The gateway checks the Connection Broker status periodically and resumes communications as soon as the agent becomes available. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.parallels.com/landing/ras-admin-guide/parallels-ras-21-administrators-guide/ras-multi-tenant-architecture/deploying-tenant-broker-and-tenants/user-authentication.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.