Authentication

Authentication is used in SharePoint 2019 to validate a user for the purpose of using SharePoint sites, lists, libraries, and documents within the farm. SharePoint then authorizes use after verifying the user has rights to a particular site within the farm. You will see this process when you use Fiddler to troubleshoot issues from a desktop where a user is signing in. You will notice a 401 error right from the start, before the user actually enters their username and password. This is to make sure the authorization has completed. It does this by authenticating to a security source first before access to the site can be given.

The default authentication for SharePoint is Windows authentication. Microsoft has always made Active Directory available for use as an authentication method for user accounts since SharePoint 2007, along with other methods we will talk about in this section. Active Directory is well-known as an authentication provider and used solely in some...