Office 365 includes a range of services, including Lync Online, SharePoint Online, OneDrive for Business, Office 2013 and of course, Exchange Online. Although moving to Exchange Online used to be the first thing organizations wanted to do, it’s now becoming common for organizations to start using other services, like OneDrive for Business or Lync Online, first.
Alternate Login ID is useful in these scenarios as it can help accelerate your pilot and deployment of Office 365. Once you have an understanding of Alternate Login ID’s features, use cases and drawbacks, it’s time to look into prerequisites and configuration steps.
You don’t need to do much to get Alternate Login ID up and running. Ideally, you’ll need the latest version of DirSync. You need to keep DirSync updated if you’re using Office 365, anyway. (At time of writing, the current version is 6862.0000.)
You can use Password Sync with Alternate Login ID, but if you’re planning on using Active Directory Federation Services, you’ll need AD FS on Windows Server 2012 R2 (sometimes called AD FS 3.0) patched with Windows 8.1 update KB2919355, which is included as part of normal Windows Server updates.