Hi D_Goossens,
I’d like to share some of the views about Dirsync with password and ADFS.
Why do we use DirSync?
So that we can manage the users in the local AD instead of the Office 365 Portal, we still need to use the online credential to log into Office 365 (need to manually type in the password).
Why do we use ADFS?
So that we can log into Office 365 by authenticated from the local AD by SSO (Single Sign-On) redirection, we can use the local AD credential to log into Office 365 (can log into Office 365 automatically in the internal network environment).
How long does DirSync synchronize?
If you add objects to your local Active Directory, they will be added to Windows Azure AD with the next synchronization. All changes that you make in your local Active Directory will be synchronized within three hours, or you can force synchronization at any time. See Synchronize your directories for more information.
Isn't it possible to sync the users, and have the same sign-in ID on both sides when performing the DirSync? (user@customer.be)
Actually this is how Dirsync works. For example, if we have a user named user@customer.be in the local AD and we haven’t added the user in Office 365, after we run DirSync, the user synced to Office 365 will get an ID named user@contoso.onmicrosoft.com; however after we add the domain in Office 365, then the synced user will be user@customer.be. In that case, the user will have the same sign-in ID in both the local AD and Office 365.