Could anyone clearly explain
- what is Sharepoint authentication realm (the one set by Set-SPAuthenticationRealm cmdlet)?
- In what cases do I need to set this realm equal for 2 (or more) farms, and in what cases do I have to set the realm ID different for the farms?
- What are the possible usage cases of the authentication realm values?
As SharePoint's documentation, as usual, only covers the simplest and superficial terms/notions and cases, this info would be very useful.