Historical
IEC/PAS 62406 Ed. 1.0 en:2005
Real-time Ethernet TCnet (Time-Critical Control Network)
specifies the protocol set necessary for RTE-TCnet, specifically of the Data Link layer and the Application layer, which is mapped on top of the Data Link layer to exploit the services in terms of the ""three-layer"" Fieldbus Reference Model which is based in part on the OSI Basic Reference Model. Both Reference Models subdivide the area of standardization for interconnection into a series of layers of specification, each of manageable size
International Electrotechnical Commission [iec]