Azure AD Domain Services
Introduced by Microsoft in October 2015, Azure AD Domain Services (AD DS) provides managed domain services such as domain join, LDAP, Kerberos, and NTLM authentication, which are fully compatible with Windows Server Active Directory. This service enables Azure Virtual Machines (VMs) and application services to use traditional Windows authentication seamlessly in the Azure cloud, eliminating the need for organizations to deploy, manage, and patch Windows Server Active Directory instances in the cloud. It's designed to simplify the task of managing authentication and authorization for applications and users in Azure, especially for those organizations looking to migrate on-premises AD-dependent applications and services to the cloud, thereby ensuring a smooth transition and continuous operation without needing significant rearchitecture.