AAD is a cloud-based directory and identity management service that provides application access management and identity protection. It's often referred to as IaaS.
We already mentioned this, but let's review it anyway. AAD is at the top level of the Azure management chain and it's directly tied to the tenant. Under the tenant, we can have multiple subscriptions, under subscriptions multiple resource groups, and under resource groups multiple resources.
A single account can have access to multiple tenants but each tenant is isolated. When a user signs in, the default directory and tenant is selected. Only resources that are under subscriptions under that tenant are available. In order to manage resources in another tenant, we must switch the directory.
AAD comes in four tiers:
- Azure Active Directory Free
- Azure Active Directory Basic
- Azure...
