So many of you probably have been wondering what type of 2FA I am using for my tests. Instead of setting up internal servers, dealing with encryption keys and various tokens, I stumbled upon a cloud service that handles all of this for you. Now before we dive into the “commercial” part (although I did not see any money from them) the basics for configuring TMG with radius are also covered in this post, so if you prefer another vendor, your own radius/2FA solution, this post still applies.
When migrating to Office 365 users must retain access to Outlook Web Access. While the guides for the OWA access are present, users see themselves being challenged for username and password multiple times. This is even worse when most users are located on Exchange 2007 in a mixed environment.
In order to cope with this problem TMG can be setup to only authenticate users once. Even more, users can also be authenticated already when they are sent to the Office365 OWA site and need to request a token from the ADFS server.