Resolved SSO solution for multiple sites

Hello Jacqui,

Thank you for your interest in RO Single Sign On.

I want to create a Joomla 5 site that controls all users

That is possible, this site is what we call the Identity Provider or in short IDP.

I want to connect 5 other Joomla 5 sites to it so that a user has one identity across all the sites and can login to each site separately

That is also possible because those sites we call Service Providers or in short SPs. However if you are logged into 1 site, you can login to all other sites without entering your credentials. If you force login on those sites, users will even be automatically logged in without intervention unless their session has expired. The login will always happen on the IDP site.

Ideally, it would be good if they logged into one site and were logged into the other at the same time but this is not a deal breaker

That is possible as I described above.

I also wanted to be able to host different groups and access levels on different sites if possible and control the user access on the individuals sites but using their central login

You can sync usergroups between the sites, not access levels. Primarily the IDP is for user authentication not authorization. Authorizations should happen on the individual sites. For example I could be an administrator on one site but only a member on another site. The sites determine what you are allowed to see and do.

Is this all possible and if so, how long to set it up

So yes, this is possible for the most part but not the access levels as I explained above. With 6 sites (1 IDP and 5 SPs) you are looking at 1 day of work to set everything up and test it.

There is one caveat I need to mention, the Joomla 5 only release is not out officially yet. It is ready but not yet released as I am going through the final testing steps. However I feel it is fine to run it as if there are any changes needed, they will be minor.

Let me know if you have any further questions.