Related: Active Directory


Some services require Directory Service, like Amazon Workspaces

Run in VPC, to implement Business Resilience and Reliability > High availability (HA), deploy multiple AZs
Can be Isolated (Like being AWS only) or integrated or act as a proxy in connector mode.

Simple AD Mode

Uses open-source Samba (software) - Wikipedia ver. 4 directory service.
Simple iD is a default go-to.
If you want to migrate people to AWS Managed Microsoft AD there you go: Migrate users from Active Directory to AWS Managed Microsoft AD - AWS Directory Service

AWS Managed Microsoft AD

Literally AD in AWS, which can be independent from on-premise service,

AD Connector

Just connects AWS Services to on-premise AD