AWS- Type of Directory Services Offered

Directory Service option	Description	Best for..
AWS Cloud Directory	Cloud-native directory to share and control access to hierarchical data between applications	Cloud applications that need hierarchical data with complex relationships
Amazon Cognito	Sign-up and sign-in functionality that scales to millions of users and federated to public social media services	Develo consumer apps or SaaS
AWS Directory Service for Microsoft Active Directory	AWS-managed full Microsoft AD (Standard or enterprise) running on Windows server 2012 R2	Enterprises that want hosted Microsoft AD or you need LDAP for Linux apps
AD connector	Allows on-premises users to log into AWS services with their existing AD credentials. Also allows EC2 instances to join AD domain	Single Sign-on for on-prem employees and for adding EC2 instances to the domain
Simple AD	Low Scale, low cost AD implementation based on Samba	Simple user directory, or you need LDAP compatibility

AD Connector vs Simple AD

AD connector	Simple AD
Must have existing AD	Standalone AD based on Samba AD
Existing AD users can access AWS resources using IAM roles	Supports user account groups, group policies, Domains
Supports MFA with existing RADIUS based infra	Kerbros based SSO
	No MFA support
	No trust relationship