Q: What is Azure AD Application Proxy?
A: Windows Server 2012 R2 has a feature called Web Application Proxy that provides several features, including:
- Reverse proxy
- Single sign-on (SSO) through integration with Active Directory Federation Services (ADFS) and the ability to support even applications that don't support claims
Azure AD Application Proxy provides an Azure hosted service that offers a similar set of capabilities. Think of it as Web Application Proxy in the cloud. Internal applications can be published to the Internet through Azure AD Application Proxy, leveraging Azure AD for the authentication. The communication to enable internal applications to be made available via Azure to the Internet is an Azure AD Application Proxy connector that's installed on one or more Windows Server 2012 R2/Windows 8.1 instances on-premises, which are relays for communication.