3.2.4.2.3 Capabilities Negotiation
Following a successful dialect negotiation, the client MUST perform a logical AND of Client.Connection.ServerCapabilities and Client.Capabilities.
The client MUST communicate these capabilities to the server in the SMB_Parameters.Capabilities field of an SMB_COM_SESSION_SETUP_ANDX Request (section 2.2.4.53.1).
The client MUST set the MaxMpxCount field in the SMB_COM_SESSION_SETUP_ANDX Request to the value of Client.Connection.MaxMpxCount.
The client SHOULD set the SessionKey field in the SMB_COM_SESSION_SETUP_ANDX Request (section 2.2.4.53.1) to the value of Client.Connection.ServerSessionKey.