IEC 62056-5-3:2017(E) specifies the DLMS/COSEM application layer in terms of structure, services and protocols for DLMS/COSEM clients and servers, and defines rules to specify the DLMS/COSEM communication profiles. It defines services for establishing and releasing application associations, and data communication services for accessing the methods and attributes of COSEM interface objects, defined in IEC 62056-6-2 using either logical name (LN) or short name (SN) referencing. This third edition cancels and replaces the second edition of IEC 62056-5-3, published in 2016. It constitutes a technical revision. The significant technical changes with respect to the previous edition are listed in Annex K (Informative).