NegotiateStream.AuthenticateAsServerAsync Method (NetworkCredential, ExtendedProtectionPolicy, ProtectionLevel, TokenImpersonationLevel)
Called by servers to authenticate the client, and optionally the server, in a client-server connection as an asynchronous operation. The authentication process uses the specified server credentials, authentication options, and extended protection policy.
Assembly: System (in System.dll)
[HostProtectionAttribute(SecurityAction.LinkDemand, ExternalThreading = true)] public virtual Task AuthenticateAsServerAsync( NetworkCredential credential, ExtendedProtectionPolicy policy, ProtectionLevel requiredProtectionLevel, TokenImpersonationLevel requiredImpersonationLevel )
- Type: System.Net.NetworkCredential
The NetworkCredential that is used to establish the identity of the client.
- Type: System.Security.Authentication.ExtendedProtection.ExtendedProtectionPolicy
The ExtendedProtectionPolicy that is used for extended protection.
- Type: System.Net.Security.ProtectionLevel
One of the ProtectionLevel values, indicating the security services for the stream.
credential is null.
The authentication failed. You can use this object to try to r-authenticate.
The authentication failed. You can use this object to retry the authentication.
Authentication has already occurred.
- or -
This stream was used previously to attempt authentication as the client. You cannot use the stream to retry authentication as the server.
Windows 95 and Windows 98 are not supported.
This object has been closed.
The policy parameter was set to Always on a platform that does not support extended protection.
When authentication succeeds, you must check the IsEncrypted and IsSigned properties to determine what security services are used by the NegotiateStream. Check the IsMutuallyAuthenticated property to determine whether mutual authentication occurred.
The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: ExternalThreading. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.