3.1.5.1 RemoteCallKerbNegotiateVersion
The RemoteCallKerbNegotiateVersion call uses the Kerberos NegotiateVersion message (section 2.2.2.1.1) to negotiate the protocol version that the Kerberos packages on the CredSSP server and CredSSP client will use to communicate. It SHOULD be called before any other calls are made.
To perform this message exchange, the CredSSP server MUST send a KerbCredIsoRemoteInput object to the CredSSP client. The CallId field MUST be set to RemoteCallKerbNegotiateVersion, and the MaxSupportedVersion member of the union MUST be populated.
To reply to the preceding input message, the CredSSP client MUST respond with a KerbCredIsoRemoteOutput object. The CallId field MUST be set to RemoteCallKerbNegotiateVersion, and the VersionToUse member of the union MUST be populated.