In the Azure AD PowerShell Module there seems to be two sets of cmdlets to manage federated domains:
For example, to add a federated domain you can useNew-MsolDomain -Authentication Federated
orNew-MsolFederatedDomain
Likewise, for converting a standard domain to a federated domain you could useSet-MsolDomainAuthentication -Authentication Federated
orConvert-MsolDomainToFederated
The documentation for the first set of cmdlets (for example, New-MsolDomain) says:
This cmdlet can be used to create a domain with managed or federated identities, although the New-MsolFederatedDomain cmdlet should be used for federated domains in order to ensure proper setup.
So why do these cmdlets exist? My guess is the 2nd set of cmdlets (like New-MsolFederatedDomain) assume you are federating with ADFS and do some extra things for you, while the 1st set only registers the domain in Azure AD and leaves the rest up to you. You would use this if you are using some other tool like PingIdentity instead of ADFS.
Can anyone confirm this?