> For the complete documentation index, see [llms.txt](https://developer.tokeninc.com/token-developer-portal-1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.tokeninc.com/token-developer-portal-1/x-platform/token-x-admin-panel-integrations/authentication-integration/external-sso.md).

# External (SSO)

Single sign on system. (If you have any own user authenticate system use this)

This feature called Sign With TOKEN.