IEC 61158-4-12:2010 specifies procedures for the transfer of data and control information from one data-link user entity to one or more user entity; the structure of the DLPDUs used for the transfer of data and control information by the protocol of this standard, and their representation as physical interface data units. This second edition cancels and replaces the first edition published in 2007 and constitutes a technical revision. The main changes with respect to the previous edition are: bug fixes and editorial improvements. This bilingual version (2012-05) corresponds to the monolingual English version published in 2010-08.