Remote Desktop Gateway Services
A standard Remote Desktop Services (RDS) deployment includes various Remote Desktop role services running on Windows Server. The RDS deployment with Azure Active Directory (Azure AD) Application Proxy has a permanent outbound connection from the server running the connector service. Other deployments leave open inbound connections through a load balancer. This authentication pattern allows you to offer more types of applications by publishing on-premises applications through Remote Desktop Services. It also reduces the attack surface of their deployment by using Azure AD Application Proxy.
You need to provide remote access and protect your Remote Desktop Services deployment with pre-authentication.
Components of system
User: Accesses RDS served by Application Proxy.
Web browser: The component that the user interacts with to access the external URL of the application.
Azure AD: Authenticates the user.
Application Proxy service: Acts as reverse proxy to forward request from the user to RDS. Application Proxy can also enforce any Conditional Access policies.
Remote Desktop Services: Acts as a platform for individual virtualized applications, providing secure mobile and remote desktop access, and providing end users the ability to run their applications and desktops from the cloud.