Use C2WTS to get a classic windows identity from a claims identity
- by Sahil Malik
SharePoint, WCF and Azure Trainings: more information
I know you’re going to find this useful at some point. A lot of backend systems still demand classic windows identities, but everything we do now has moved to claims. So sometimes (albeit rare), we have to translate a claims identity into a classic windows identity. This is where the “Claims to Windows Token Service” comes into play. SharePoint 2010 and 2013 make use of this but you can use this in any .NET application. First of all, there are some basic requirements for this to work, First, you will need the string value of a UPN claim. Just a string value, really! This means you can also use FBA or anything else. The “proper” way to do this of course is that you must originate this from a AD backed claim. So a user authenticated using ADFS or similar would be perfect. Just remember that you must issue the UPN claim.
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