This Amendment introduces optional enhancements to the protocol for providing the connection-mode Transport Service (see ITU-T Rec. X.224 | ISO/IEC 8073), to take into account the requirements of OSI users who do not have a need for full implementation. This Amendment permits relaxation of the strict conformance requirements to allow an implementation which will never need to support expedited data, or need to operate over connection-mode network service, to still be conformant without necessarily implementing either or both of these facilities.