AuthenticationSchemes Enumeration


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Specifies protocols for authentication.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

Namespace:   System.Net
Assembly:  System (in System.dll)

Public Enumeration AuthenticationSchemes

Member nameDescription

Specifies anonymous authentication.


Specifies basic authentication.


Specifies digest authentication.


Specifies Windows authentication.


Negotiates with the client to determine the authentication scheme. If both client and server support Kerberos, it is used; otherwise, NTLM is used.


No authentication is allowed. A client requesting an HttpListener object with this flag set will always receive a 403 Forbidden status. Use this flag when a resource should never be served to a client.


Specifies NTLM authentication.

This enumeration is used to specify the method used to authenticate client requests being processed by HttpListener objects.

Note   Basic authentication requires the exchange of a password and should therefore be avoided except in the case of secure, encrypted connections.

The following code example demonstrates using the Negotiate enumeration value to specify that clients are authenticated using the Negotiate security protocol.

Console.WriteLine("Listening for {0} prefixes...", listener.Prefixes.Count)
Dim context As HttpListenerContext = listener.GetContext()
Dim request As HttpListenerRequest = context.Request
Console.WriteLine("Received a request.")
' This server requires a valid client certificate
' for requests that are not sent from the local computer.

' Did the client omit the certificate or send an invalid certificate?
If request.IsAuthenticated AndAlso request.GetClientCertificate() Is Nothing OrElse request.ClientCertificateError <> 0 Then
    ' Send a 403 response.
    Dim badCertificateResponse As HttpListenerResponse = context.Response
    Console.WriteLine("Client has invalid certificate.")
    Continue Do
End If

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.1
Windows Phone
Available since 8.1
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