WG 15 - TC 13/WG 15

IEC 62055-42:2022, specifies a token generation mechanism and token structure for smart prepayment functionality in markets where IEC 62055-41 compliant systems are not used, and where a different security mechanism is required by project-specific or national requirements. This document specifies token structure, authentication and an anti-replay mechanism, token operating model, and protocol.
This document is informed by the STS Association key management services, and by the key management mechanisms used within the DLMS/COSEM security model within IEC 62056‑6‑2. Reference is made to the international STS token standards (IEC 62055-41, IEC 62055-51 and IEC 62055-52) for payment metering systems, and interworking has been considered where appropriate in terms of token carrier ranges in the decimal domain. IEC 62055-41 tokens and those described in this document are not interoperable, however their domains are designed to be mutually exclusive to ensure the two kinds of tokens do not interfere with each other.
Metering application processing and functionality, HAN interface commands and attributes, WAN interface commands and attributes are outside the scope of this document; however, reference is made to other standards in this regard.
The mechanism for auditing and retrieving data from the meter relating to tariffication, meter readings, profile data and other legal metrology information is outside the scope of this document; however, this is defined as part of any overall metering solution. Such interfaces for retrieving data from a meter may be defined using suitable protocols such as DLMS/COSEM as defined in the IEC 62056 series.

IEC 62055-31:2022 applies to newly manufactured, static watt-hour payment meters of accuracy classes 0,5, 1 and 2 for direct connection, for the measurement of alternating current electrical energy consumption of a frequency in the range 45 Hz to 65 Hz that include a supply control switch for the purpose of interruption or restoration of the electricity supply to the load in accordance with the current value of the available credit maintained in the payment meter. It does not apply to static watt-hour payment meters where the voltage across the connection terminals exceeds 1 000 V (line-to-line voltage for meters for polyphase systems). It applies to payment meters for indoor application, operating under normal climatic conditions where the payment meter is mounted as for normal service (i.e. together with a specified matching socket where applicable). Payment meters are implementations where all the main functional elements are incorporated in a single enclosure, together with any specified matching socket. There are also multi-device payment metering installations where the various main functional elements, such as the measuring element, the user interface unit, token carrier interface, and the supply control switch are implemented in more than one enclosure, involving additional interfaces. Functional requirements that apply to payment meters are also defined in this document, and include informative basic functional requirements and tests for the prepayment mode of operation in Annex A. Allowances are made for the relatively wide range of features, options, alternatives, and implementations that may be found in practice. The diverse nature and functionality of payment meters prevent the comprehensive specification of detailed test methods for all of these requirements. However, in this case, the requirements are stated in such a way that tests can then be formulated to respect and validate the specific functionality of the payment meter being tested. This document does not cover specific functionality or performance requirements for circuit protection, isolation or similar purposes that may be specified through reference to other specifications or standards. Safety requirements removed from Edition 1.0 have been replaced with references to the safety requirements now contained in IEC 62052-31:2015, the product safety standard for newly manufactured electricity meters. In-service safety testing (ISST) is not covered by IEC 62052-31:2015 and is left to national best practice usually as an extension of existing in-service testing (IST) of metrology stability. This document does not cover software requirements. This document covers type-testing requirements only. For acceptance testing, the requirements given in IEC 62058‑11:2008 and IEC 62058-31:2008 may be used. Dependability aspects are addressed in the IEC 62059 series of standards. Additional reliability, availability, maintenance and life cycle aspects are provided by IEC TC 56. This document does not cover conformity tests and system compliance tests that may be required in connection with legal or other requirements of some markets. This second edition cancels and replaces the first edition published in 2005. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Title modified.
b) Removal of the contents of Annex C relating to the requirements for the supply control switch, and added reference to IEC 62052-31:2015 which contains the relevant requirements.

IEC 62055-41:2018 is also available as IEC 62055-41:2018 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 62055-41:2018 specifies the application layer protocol of the standard transfer specification (STS) used for transferring units of credit and other management information from a point of sale (POS) system to an STS-compliant payment meter in a one-way token carrier system. It is primarily intended for application with electricity payment meters without a tariff employing energy-based tokens, but may also have application with currency-based token systems and for services other than electricity. It is intended for use by manufacturers of payment meters that have to accept tokens that comply with the STS and also by manufacturers of POS systems that have to produce STS-compliant tokens and is to be read in conjunction with IEC 62055-5x series. This third edition cancels and replaces the second edition of IEC 62055-41, issued in 2014. It constitutes a technical revision. The main technical changes with regard to the previous edition are as follows:
- currency transfer tokens for electricity, water, gas and time metering;
- finer resolution for gas and time credit transfer;
- common code PAN for 2 and 4 digit manufacturer codes;
- reserved MfrCode values for certification and testing purposes;
- provision for DLMS/COSEM as a virtual token carrier type;
- addition of DKGA04, an advanced key derivation function from 160-bit VendingKey;
- withdrawal of DES for EA09 and TDES for DKGA03 cryptographic algorithms, but DES for DKGA02 remains in use;
- addition of MISTY1 cryptographic algorithm using a 128-bit DecoderKey with supporting key change tokens;
- transfer of SGC values to the meter via key change tokens;
- revision of the test/display token requirements;
- revision of the KMS to reflect current best practice;
- revision of the TID roll over management guidelines;
- definition of BaseDate is referenced to Coordinated Universal Time;
- some clarifications and additional examples have been added.

specifies a physical layer protocol of the standard transfer specification (STS) for transferring units of credit and other management information between a point-of-sale (POS) system and an STS-compliant electricity payment meter.

IEC 62055-31:2005 applies to newly manufactured, static watt-hour payment meters of accuracy classes 1 and 2 for direct connection, for the measurement of alternating current electrical energy consumption of a frequency in the range 45 Hz to 65 Hz that include a load switch for the purpose of interruption or restoration of the electricity supply to the load in accordance with the current value of the available credit maintained in the payment meter. It does not apply to static watt-hour payment meters where the voltage across the connection terminals exceeds 600 V (line-to-line voltage for meters for polyphase systems). It applies to payment meters for indoor application only, where the payment meter shall be mounted as for normal service Functional requirements that apply to payment meters are also defined and include informative basic functional requirements and tests for the prepayment mode of operation in Annex A. This bilingual version (2013-05) corresponds to the monolingual English version, published in 2005-09.

sets out a framework for the integration of standards into a system specification for electricity payment metering systems. It addresses the payment metering system application process, generic processes, generic functions, data elements, system entities and interfaces that exist in present payment metering systems.