Domain Mapping:
This feature auto redirects users to a particular IDP based on the user domain.
In domain mapping you can map the domain in order to auto-redirect to a particular IDP when the user tries to log in with the domain email.
You can Map more than 1 domain for any IDP by entering the domains separated by a semicolon (;).
Domain Restriction:
Domain Restriction provides the functionality to allow or restrict the users of a particular domain to log in or register.
It has the following 2 ways to use this feature:
Allow users to log in with specified domains
Deny users to log in with specified domains
You can even provide multiple domains to restrict by entering the domain separated by a semicolon (;). Similarly, you can allow users of a particular domain to log in likewise.