This presentation helps you taking the right decision if you want to extend your OnPrem Active Directory infrastructure to Microsoft Azure (Microsoft IDaaS offer). All options/scenarios, including PHS (Password Hash Synchronization), PTA (Pass-Through Authentication) and ADFS (Active Directory Federation Services) are detailed in this slide. This document is available to download here : https://gallery.technet.microsoft.com/Design-Guide-Extend-your-30308441