The TcpUseRFC1122UrgentPointer property indicates whether TCP uses the RFC 1122 specification or the mode used by Berkeley ...

The TcpUseRFC1122UrgentPointer property indicates whether TCP uses the RFC 1122 specification or the mode used by Berkeley Software Design (BSD) derived systems, for urgent data. The two mechanisms interpret the urgent pointer differently and are not interoperable. Windows 2000 and Windows NT version 3.51 and higher defaults to BSD mode. If TRUE, urgent data is sent in RFC 1122 mode. Default: FALSE.