Fast user switching
Updated: August 23, 2010
Fast user switching (FUS) is a feature that allows users to switch between user accounts on a single PC without quitting applications and logging off. This is a typical scenario for home users sharing a single PC. This topic provides guidelines for designing a fingerprint management application (FMA) that supports FUS.
This information applies to the following operating systems:
- Windows Server 2008 R2
- Windows 7
The Windows Biometric Framework (WBF) provides a set of functions to implement FUS efficiently on Windows. For more information, see WinBioLogonIdentifiedUser function.
To do FUS, your FMA must store user credentials securely. We recommend that you store credentials by using the Windows Biometric Credential Manager. The Windows Biometric Credential Manager uses the credential vault, which uses the Data Protection API (DPAPI) to store credentials. For more information, see Windows Data Protection.
FUS applications must handle FUS events before checking for other unhandled swipe events. For example, if launching an application is associated with a scan of user A’s right index finger, but user B is logged on when user A scans his or her right index finger, your FMA should log on user A but it should not start the application unless user A scans his or her right index finger again.
Your FMA must unregister for unhandled swipes if the application is per session. The FMA must unregister when the user session is not interactive only. It will need to re-register when the user unlocks or logs back on.
If your FMA does not unregister, then it is not able to use FUS to switch away from the user you just switched to. If the application is running on a desktop session that you are not in, then swipes cannot be captured by the application to make a FUS request.