The committee for IEEE 802.3 has been mandated as ISO/IEC, JTC 1/SC, 25 WG3, and TIA standardization for some time ago to propose and standardize the connectors. Manufacturers and committees are well-known numerous participants in the selection process.
The application and transmission channel have been defined by IEEE802.3. The transmission requirements and the parameters for passive cabling structures have been described by the ISO/IEC, JTC 1, SC25, and WG3 for building smart homes and data centers. IEC SC 48B has been defined by the electrical and IEC SC 46C describes the mechanical parameters for connectors and cables.
The possible connectors have been described by the current version of the document which can be used on Medium Dependent Interface (MDI). As per the IEC 63171-X series of standards, the SPE connectors are described for the difference in the mating face, dimensions, and mechanical properties.
The electrical properties of connectors are as per IEEE 802.3cg i.e. (SPE 10 Mbit/s in 1000 m), explained for the first time under the MDI heading. According to IEC 63171-1(LC style) and IEC 63171-6 (T1 industrial style), terminals and connectors are named also MDI.
Source:- ISO Standards