Single Sign On using Windows Authentication

[RichardWatson]

I wish to deploy a Silverlight application using a single sign on approach to authentication, i.e. the users credentials are their Windows domain credentials.  ArcGIS Server services are secured using Windows credentials as well.

ArcGIS Server service security is a token based approach which seems to indicate that single sign on is not possible.  How can I generate a token unless I ask the user for their password (which is the very thing I wish to avoid)?

[JenniferNery]

I'm not sure whether you found answers already.

If not, here's a link to configuring token service. It seems you can leverage existing Windows user accounts.
http://help.arcgis.com/en/arcgisserver/10.0/help/arcgis_server_dotnet_help/index.html#//0093000000q5....

Also, here's an example of retrieving token from a given user credentials: http://blogs.esri.com/Dev/blogs/silverlightwpf/archive/2010/02/15/How-to-use-secure-ArcGIS-Server-se....

If you are using WPF API v2.1, layers have Credentials property. You should be able to re-use the same Credentials. If you are using Silverlight, your web browser handles user authentication.