Multi-Factor Authentication (MFA) is the concept that hardens the security of authentication services by adding an additional layer of verification to conventional user name and password based authentication. For example, this could be an SMS, a phone call or smart card, etc…
MFA has been around in the industry for quite some time now and many of us have been using it in one way or another in our day-to-day life. Be it your personal Outlook.com, Gmail, Yahoo! email accounts, online banking system or even your favorite social media network, there’s a high chance you’re using MFA to harden the security of your service.
As an Office 365 administrator, you have the option to enable MFA for your organization’s users if you require this additional layer of security. Features you get with any regular Office 365 subscription are sufficient enough to start with MFA, but if you want additional features such as advanced reporting, integration with on-premises application, etc., then you have to use Azure Multi-Factor Authentication which comes bundled with Azure Active Directory Premium and Enterprise Mobility Suite or which also can be purchased as a stand-alone license.
MFA in Office 365 helps users to verify their identity in multiple ways. Users can choose from to receive an SMS, an automated phone call, a smart phone app generated code or a notification on their smart phone (my favorite) where the user can simply tap on an action to perform. This notifications on the smart phone feature (as seen in below screen shot) truly a smart function that does indeed save time.
I have put together a simple step-by-step guide on how to configure MFA for Office 365 at TechNet Gallery which you can access by clicking here.