Office 365 provides the flexibility to temporarily or permanently maintain a hybrid environment so you can move to the cloud gradually, or maintain some users on-premises indefinitely. Many organizations using Office 365 in a hybrid cloud and on-premises environment choose to secure user access to Office 365 with two factor authentication. In doing so, users can also have convenient, Single Sign On (SSO) to both Office 365 services and on-premise applications. Considerations in implementing two factor authentication for Office 365 include using Active Directory and Active Directory Federation Services technologies.
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