
ASP.NET Core 5 for Beginners
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Chances are that if you have logged in to a corporate computer the past 20 years, you have used Active Directory, whether you are aware of it or not. AD was introduced with Windows Server 2000 and extended the domain concept introduced in Windows NT 4.0 to provide a complete implementation of centralized identities. When you logged in to your Windows desktop, it provided fairly pain-free access to file shares and servers in an organization as long as you were seated in the office.
With AD, you need at least a couple of servers on-premises and accompanying infrastructure. This isn't feasible in the cloud world of today, but Microsoft built upon what they had to provide Azure Active Directory (AAD) as a cloud identity provider, breaking free from the constraints of physical locations at the same time.
AD is based on older identity protocols, so the OAuth flows and OIDC are not natively supported, but require the use of Active Directory...