How to determine if the current user is authenticated by NTLM or Kerberos in a WebPart’s C# Code?

Hi,

I need to build a WebPart that show the authentication method for the current user. The webpart need to show NTLM or Kerberos.

When I check HttpContext.Current.User.Identity.AuthenticationType, it returns Negotiate. I can’t trust Negotiate as it might be either of NTLM or Kerberos.

What is best method in a SharePoint web part code to clearly determine the authentication method?

Thank you,