IEC 62056-7-5:2016

IEC 62056-7-5 ®
Edition 1.0 2016-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electricity metering data exchange – The DLMS/COSEM suite –
Part 7-5: Local data transmission profiles for Local Networks (LN)

Échange des données de comptage de l'électricité – La suite DLMS/COSEM –
Partie 7-5: Profils de transmission de données locales pour réseaux locaux (LN)

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IEC 62056-7-5 ®
Edition 1.0 2016-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electricity metering data exchange – The DLMS/COSEM suite –

Part 7-5: Local data transmission profiles for Local Networks (LN)

Échange des données de comptage de l'électricité – La suite DLMS/COSEM –

Partie 7-5: Profils de transmission de données locales pour réseaux locaux (LN)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20; 35.100.01; 91.140.50 ISBN 978-2-8322-3326-9

– 2 – IEC 62056-7-5:2016  IEC 2016
CONTENTS
FOREWORD. 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 10
3 Terms, definitions and abbreviations . 11
3.1 Terms and definitions . 11
3.2 Abbreviations . 11
4 Targeted communication environments . 11
5 Use of the communication layers for these profiles . 12
5.1 Information related to the use of the standards specifying the lower layers . 12
5.2 Structure of the profile . 12
5.3 Use of the lower layers . 13
5.3.1 Overview . 13
5.3.2 Physical layer . 14
5.3.3 MAC layer . 14
5.3.4 Data link layer . 14
5.4 Service mapping and adaptation layers . 14
5.4.1 For the default HDLC based data link layer . 14
5.4.2 For other lower layers . 15
5.5 Registration and connection management . 15
6 Identification and addressing scheme . 15
6.1 General identification and addressing scheme . 15
6.2 Addressing for the default HDLC based data link layer . 15
6.3 Addressing for other data link layers . 15
7 Specific considerations for the application layer services . 15
7.1 Overview . 15
7.2 Application Association establishment and release: ACSE services . 15
7.3 xDLMS services . 15
7.4 Security mechanisms . 16
7.5 Transferring long application messages . 16
7.6 Media access, bandwidth and timing considerations . 16
8 Communication layer configuration and management . 17
9 The COSEM application process (AP) . 17
9.1 Model and services . 17
9.2 COSEM interface classes (IEC 62056-6-2) to configure the LDTI . 18
9.3 Security environment (not valid for legacy mode) . 19
9.4 Restrictions for interfaces supporting “Legacy operating modes” . 20
10 Additional considerations for the use of this profile – Safety . 21
Annex A (normative) Media specific profile: Optical interface . 22
A.1 IEC 62056-21 port . 22
A.2 IEC 62056-21 port operating in legacy mode . 23
Annex B (normative) Media specific Profile: TP with carrier signalling Interface . 25
B.1 IEC 62056-3-1 port . 25
B.2 IEC 62056-3-1 port operating in legacy mode . 26
Annex C (normative) Media specific profile: EIA-485, TIA-232-F interface . 29

C.1 Electrical port RS485/232 . 29
Annex D (normative) Media specific profile: M-Bus EN 13757-2 . 31
D.1 M-Bus with the HDLC based data link layer . 31
Annex E (normative) IP profile . 33
E.1 IP profile . 33
Annex F (informative) LDTI configuration examples . 35
F.1 Example 1: only one value (active energy A+) pushed . 35
Annex G (informative) LDTI encoding examples . 37
G.1 xDLMS APDUs used (without protection and without general-block-transfer) . 37
G.2 Example 1: Only one value is pushed . 37
G.3 Example 2: The OBIS code and one value is pushed. 38
Index . 40

Figure 1 – LDTI DLMS/COSEM client as part of a consumer device . 9
Figure 2 – LDTI DLMS/COSEM client as part of a local adaptor . 9
Figure 3 – Entities and interfaces of a smart metering system . 12
Figure 4 – IEC 62056-7-5 LDTI interface in the context of the smart metering
architecture . 12
Figure 5 –Local data transmission reference model . 13
Figure 6 – LDTI – the interface to a pre-established DLMS/COSEM LDTI client . 18
Figure 7 – Interface classes modelling the push operation . 19
Figure 8 – Example of a security environment for an LDTI using global keys . 20
Figure 9 – LDTI – operating in “legacy mode” . 21
Figure A.1 – Structure of the optical interface profile . 22
Figure A.2 – Structure of the optical interface – “operating in legacy mode” – profile . 24
Figure B.1 – Structure of the TP with carrier signalling profile . 25
Figure B.2 – Structure of the TP with carrier signalling – “operating in legacy mode” –
profile . 27
Figure C.1 – Structure of the RS485/232 profile . 29
Figure D.1 – Structure of the “M-Bus with HDLC based data link layer” profile . 31
Figure E.1 – Structure of the IP profile . 33

Table 1 – Features of communication profiles using DLMS/COSEM compatible and
legacy protocol modes . 9
Table 2 – Conformance block for the LDTI association. 16
Table 3 – Configuration of a LDTI operating in "legacy mode" . 20
Table A.1 – Mandatory setup attribute values for an optical IEC 62056-21 interface
supporting IEC 62056-5-3 . 23
Table A.2 – Mandatory setup attribute values for an optical IEC 62056-21 operating in
the “legacy mode” . 24
Table B.1 – Mandatory setup attribute values for a TP IEC 62056-3-1 supporting
IEC 62056-5-3 . 26
Table B.2 – Mandatory setup attribute values for a TP IEC 62056-3-1 operating in the
“legacy mode” . 28
Table C.1 – Mandatory setup attribute values for an electrical RS485/232 IEC 62056-
21 interface supporting IEC 62056-5-3 . 30

– 4 – IEC 62056-7-5:2016  IEC 2016
Table D.1 – Mandatory setup attribute values for an M-Bus port with HDLC based data
link layer . 32
Table E.1 – Mandatory setup attribute values for an IP port . 34
Table F.1 – Configuration example: one value pushed every 10 s via optical port . 35

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICITY METERING DATA EXCHANGE –
THE DLMS/COSEM SUITE –
Part 7-5: Local data transmission profiles for Local Networks (LN)

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
The International Electrotechnical Commission (IEC) draws attention to the fact that it is claimed that compliance
with this International Standard may involve the use of a maintenance service concerning the stack of protocols on
which the present standard IEC 62056-7-5 is based.
The IEC takes no position concerning the evidence, validity and scope of this maintenance service.
The provider of the maintenance service has assured the IEC that he is willing to provide services under
reasonable and non-discriminatory terms and conditions for applicants throughout the world. In this respect, the
statement of the provider of the maintenance service is registered with the IEC. Information may be obtained from:
DLMS User Association
Zug/Switzerland
www.dlms.com
International Standard IEC 62056-7-5 has been prepared by technical committee 13:
Electrical energy measurement and control.

– 6 – IEC 62056-7-5:2016  IEC 2016
The text of this standard is based on the following documents:
CDV Report on voting
13/1605/CDV 13/1650/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62056 series, published under the general title Electricity metering
data exchange – The DLMS/COSEM suite, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
INTRODUCTION
As defined in IEC 62056-1-0, the IEC 62056 DLMS/COSEM suite provides specific
communication profile standards for communication media relevant for smart metering.
Such communication profile standards specify how the COSEM data model and the
DLMS/COSEM application layer can be used on the lower, communication media-specific
protocol layers.
Communication profile standards refer to communication standards that are part of the
IEC 62056 DLMS/COSEM suite or to any other open communication standard.
This International Standard specifies DLMS/COSEM communication profiles for transmitting
metering data modelled by COSEM interface objects through Local Data Transmission
Interfaces (LDTI). The LDTI may be part of a meter or of a Local Network Access Point
(LNAP) hosting a DLMS/COSEM server.
The specification of the communication profiles follows the rules defined in
IEC 62056-5-3:2016, Annex A.
A major driver for the introduction of smart metering is to provide the consumer with suitable
metering information to optimise his/her energy consumption and/or production. For that
purpose, smart meters are equipped with local interfaces providing metering data for the
consumer on consumer devices.
IEC 62056-21 and IEC 62056-3-1 are communication standards that specify direct local data
exchange and data exchange through local networks. They provide protocol modes that
support the DLMS/COSEM application layer and thus the COSEM object model. They also
specify legacy modes that do not support the DLMS/COSEM application layer.
In order to allow connecting legacy consumer equipment to the LDTI, this International
Standard also specifies communication profiles using protocol modes that do not support the
DLMS/COSEM application layer.
It is assumed, however, that in all cases the metering application is modelled by COSEM
interface objects.
It is also assumed that the meter has interfaces that fully support DLMS/COSEM and allow
the configuration of the local data transmission interface by a DLMS/COSEM client.
The requirements on the physical type of the interface, the choice of the data transmitted and
the transmitting pattern highly depends on the markets and projects the meter is designed for.

– 8 – IEC 62056-7-5:2016  IEC 2016
ELECTRICITY METERING DATA EXCHANGE –
THE DLMS/COSEM SUITE –
Part 7-5: Local data transmission profiles for Local Networks (LN)

1 Scope
This part of IEC 62056 specifies DLMS/COSEM communication profiles for transmitting
metering data modelled by COSEM interface objects through a Local Data Transmission
Interface (LDTI). The LDTI may be part of a meter or of a Local Network Access Point (LNAP)
hosting a DLMS/COSEM server.
The main body of this standard specifies the common aspects of the different communication
profiles for the LDTI interface.
The Annexes specify the communication protocol specific elements. The Annexes form an
integral part of this International Standard.
Annex A (normative) specifies a communication profile using the protocol specified in
IEC 62056-21. Clause A.1 specifies the communication profile that supports the
DLMS/COSEM application layer and Clause A.2 specifies the communication profile using the
legacy Mode D. The physical interface is the optical interface specified in IEC 62056-21:2002,
4.3.
Annex B (normative) specifies a communication profile using the protocol specified in
IEC 62056-3-1. Clause B.1 specifies the communication profile that supports the
DLMS/COSEM application layer and Clause B.2 specifies the communication profile using the
legacy mode. The physical interface is twisted pair using carrier signalling known as the
Euridis Bus.
Annex C (normative) specifies a communication profile based on the DLMS/COSEM 3-layer,
connection oriented HDLC based profile specified in IEC 62056-7-6. The physical interface is
RS 485 or TIA-232-F.
Annex D (normative) specifies a communication profile using the physical layer specified in
EN 13757-2 and the HDLC based data link layer specified in IEC 62056-46. The physical
interface is twisted pair with baseband signalling.
Annex E (normative) species a communication profile using UDP/IP. The physical layer is out
of the scope of this International Standard.
The communication profiles in Clauses A.1, B.1, and Annexes C, D and E support the
DLMS/COSEM application layer.
Annex F (informative) specifies an LDTI configuration example.
Annex G (informative) provides encoding examples.
Additional communication profiles for other media/communication protocols may be added in
the future.
Table 1 shows the features of communication profiles using DLMS/COSEM compatible and
legacy protocol modes.
Table 1 – Features of communication profiles using DLMS/COSEM
compatible and legacy protocol modes
Communication profiles supporting
Feature
DLMS/COSEM compatible modes Legacy modes
COSEM interface objects; any attribute COSEM interface objects; a limited set
Application model
value can be transmitted of attribute values can be transmitted
Protocol specific
Data formats A-XDR encoded
(typically ASCII strings)
DLMS/COSEM application
Yes (xDLMS APDUs) No
layer support
Cryptographic protection COSEM attributes and COSEM APDUs Out of scope (protocol specific)
Time or event based, controlled by
Time or event based.
COSEM interface objects.
Data transmission triggers
Interface specific restrictions may
Refresh rate can support time-critical
apply.
applications.
The consumer device may directly support the LDTI communication protocol and data
formats. In this case the LDTI DLMS/COSEM client is part of the consumer device as shown
in Figure 1.
When the consumer device does not support the LDTI communication protocol and data
formats then a local adaptor is necessary converting the communication medium and protocol
of the LDTI to the communication means of the consumer device. In this case, the local
adaptor may be part of the meter or LNAP as shown in Figure 2. The local adaptor and the
data exchange between the local adaptor and the consumer device are out of the scope of
this International Standard.
This difference is not relevant for this standard, so the arrangement shown in Figure 1 is
assumed.
The consumer device is also out of the scope of this International Standard.
Consumer device
DLMS/COSEM
LDTI
Consumer
server
LDTI
DLMS/COSEM
application
client
In scope Not in scope
IEC
Figure 1 – LDTI DLMS/COSEM client as part of a consumer device
Local adaptor
Consumer device
Consumer communication
DLMS/COSEM
LDTI
Consumer
medium
server
LDTI
DLMS/COSEM
application
client
In scope Not in scope
IEC
Figure 2 – LDTI DLMS/COSEM client as part of a local adaptor

– 10 – IEC 62056-7-5:2016  IEC 2016
The scope of these communication profiles is restricted to aspects concerning the use of
communication protocols in conjunction with the DLMS/COSEM data models. Data structures
specific to a communication protocol should be defined in the specific protocol standards. Any
project specific definitions of data structures and data contents shall be provided in project
specific companion specifications.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-300, International Electrotechnical Vocabulary – Electrical and electronic
measurements and measuring instruments – Part 311: General terms relating to
measurements – Part 312: General terms relating to electrical measurements – Part 313:
Types of electrical measuring instruments – Part 314: Specific terms according to the type of
instrument
IEC 60950-1:2005, Information technology equipment – Safety – Part 1: General requirements
Amendment 1:2009
Amendment 2:2013
IEC TR 62051, Electricity metering – Glossary of terms
IEC TR 62051-1, Electricity metering – Data exchange for meter reading, tariff and load
control – Glossary of terms – Part 1: Terms related to data exchange with metering equipment
using DLMS/COSEM
IEC 62052-31 Electricity metering equipment (AC) – General requirements, tests and test
conditions – Part 31: Product safety requirements and tests
IEC 62056-1-0, Electricity metering data exchange – The DLMS/COSEM suite – Part 1-0:
Smart metering standardization framework
IEC 62056-21:2002, Electricity metering – Data exchange for meter reading, tariff and load
control – Part 21: Direct local data exchange
IEC 62056-3-1:2013, Electricity metering data exchange – The DLMS/COSEM suite –
Part 3-1: Use of local area networks on twisted pair with carrier signalling
IEC 62056-46: 2002, Electricity metering – Data exchange for meter reading, tariff and load
control – Part 46: Data link layer using HDLC protocol
Amendment 1:2006
IEC 62056-4-7:2015, Electricity metering data exchange – The DLMS/COSEM suite –
Part 4-7: DLMS/COSEM transport layer for IP networks
IEC 62056-5-3:2016, Electricity metering data exchange – The DLMS/COSEM suite –
Part 5-3: DLMS/COSEM application layer
IEC 62056-6-1:2015, Electricity metering data exchange – The DLMS/COSEM suite –
Part 6-1: Object Identification System (OBIS)
IEC 62056-6-2:2016, Electricity metering data exchange – The DLMS/COSEM suite –
Part 6-2: COSEM interface classes

IEC 62056-9-7, Electricity metering data exchange – The DLMS/COSEM suite – Part 9-7:
Communication profile for TCP-UDP/IP networks
ISO/IEC 13239:2002, Information technology – Telecommunications and information
exchange between systems – High-level data link control (HDLC) procedures
EN 13757-2, Communication systems for and remote reading of meters – Part 2: Physical and
link layer
3 Terms, definitions and abbreviations
For the purposes of this document, the terms and definitions in IEC 60050-300, IEC TR
62051, IEC TR 62051-1 as well as the following apply.
NOTE Where there is a difference between the definitions in the glossary and those contained in product
standards produced by TC 13, then the latter take precedence in applications of the relevant standard.
3.1 Terms and definitions
3.1.1
communication medium
physical medium to transmit signals carrying information
3.1.2
Local Data Transmission Interface
LDTI
interface providing data at the location of the DLMS/COSEM server device
3.2 Abbreviations
AA Application Association
AARE A-Associate Response – an APDU of the ACSE
AARQ A-Associate Request – an APDU of the ACSE
AP Application Process
LDTI Local Data Transmission Interface
Sys-T System Title as defined in IEC 62056-5-3:2016
4 Targeted communication environments
This clause identifies the communication environment(s), for which the communication profiles
are specified.
Figure 4 shows the LDTI in the context of the smart metering architecture introduced in
IEC 62056-1-0. Typically the LDTI is part of the metering device and therefore covers the H1
interface.
NOTE The data transmitted via the LDTI is generic enough to support any consumer application; i.e. it is not
limited to „Simple Consumer Displays“.
However, it is also possible that the LDTI becomes part of an LNAP supporting the H2
interface as shown in Figure 3 and Figure 4. For both cases the scope as defined in Clause 1

– 12 – IEC 62056-7-5:2016  IEC 2016
applies. In particular, it is always assumed that the LDTI is part of a device including a
DLMS/COSEM server.
Simple
Metering H1
Consumer
Device
Home Automation
Display
System
G1 C M
L
M
G1
LNAP Local Network H2
Access Point
N
C C
H3
NNAP Neighbourhood Network
Access Point
G2
G1
HES Head End System
IEC
Figure 3 – Entities and interfaces of a smart metering system
Simple
Metering H1
Consumer
Device
Home Automation
Display
System
G1 C M
L
M
G1
LNAP Local Network H2
Access Point
N
C C
NNAP Neighbourhood Network H3
Access Point
G1 G2
HES Head End System
IEC
Figure 4 – IEC 62056-7-5 LDTI interface in the context
of the smart metering architecture
5 Use of the communication layers for these profiles
5.1 Information related to the use of the standards specifying the lower layers
Detailed information on a particular, medium specific profile can be found in the
corresponding Annex.
5.2 Structure of the profile
Figure 5 shows the common reference model used for the local data transmission profiles. It
is based on the collapsed three layer architecture typically used in the IEC 62056 profiles.
WAN Wide Area Network
WAN Wide Area Network
NN Neighbourhood Network
NN Neighbourhood Network
LN Local Network
LN Local Network
LDTI
LDTI
The Application Process, the application layer and the data link layer are specified in the
IEC 62056 standards referenced in Figure 5. HDLC is the default data link layer – other (link)
layers may be used for media specific profiles. The medium specific profiles are described in
the Annexes of this International Standard.
NOTE The box „other layers“ in Figure 5 may include UDP and IP.
Due to the limited functionality of the local data transmission interface some restrictions may
apply to the Application Process, the application layer and the data link layer as described in
Clauses 5, 7 and 9.
For interfaces based on “legacy operating modes” of IEC 62056-21:2002 and IEC 62056-3-
1:2013 – not supporting the transport of xDLMS-APDUs – the COSEM application process
just provides the functionality to select the data and the re-transmission period for the
interface (see 9.4).
COSEM Application Process
IEC 62056-6-1, IEC 62056-6-2
DLMS/COSEM Application layer
IEC 62056-5-3
xDLMS-APDUs:
• General-Glo-Ciphering
• General-Block-Transfer
• Data-Notification
HDLC based data link
layer Other
layers
IEC 62056-46
frame format type 3
"legacy operating modes"
of
IEC 62056-21
and
Medium specific Medium specific
IEC 62056-3-1
lower layers lower layers
IEC
Figure 5 –Local data transmission reference model
5.3 Use of the lower layers
5.3.1 Overview
The profile specifications in the Annexes of this International Standard contain the relevant
information and the references to the appropriate standards for the lower layers. In order to
provide interoperability for the configuration of the different media, the corresponding COSEM
setup interface classes shall be considered. For new media the set of setup interface classes
in IEC 62056-6-2 will be extended.

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5.3.2 Physical layer
The IEC 62056 series offers a variety of standards supporting the physical media for a local
interface in the electricity metering environment:
• electrical current loop as described in IEC 62056-21:2002, 4.1 with the configuration
interface class defined in IEC 62056-6-2:2016, “IEC local port setup” (class_id: 19);
• electrical V24/V28 as described in IEC 62056-21:2002, 4.2 with the configuration interface
class defined in IEC 62056-6-2:2016, “IEC local port setup” (class_id: 19);
• optical as described in IEC 62056-21:2002, 4.3 with the configuration interface class
defined in IEC 62056-6-2:2016, “IEC local port setup” (class_id: 19);
• electrical twisted pair with carrier signalling as described in IEC 62056-3-1:2013, 5.1 with
the configuration interface class defined in IEC 62056-6-2:2016, “IEC twisted pair (1)
setup” (class_id: 24);
• IP ( with UDP, see Annex E) based with the configuration interface class defined in
IEC 62056-6-2:2016, “TCP-UDP setup” (class_id: 41);
• other physical media may be considered, too.
5.3.3 MAC layer
For the default HDLC based data link layer the MAC layer is defined in IEC 62056-46 as a
sublayer of the Data Link layer. For non-HDLC based data link layers other MAC layers may
be referenced in the Annexes.
5.3.4 Data link layer
5.3.4.1 HDLC based data link layer
The default data link layer is the HDLC based data link layer as specified in IEC 62056-46.
The HDLC based data link layer is configured by means of the interface class “IEC HDLC
setup” (class_id: 23). For each physical interface one instance of this class is provided. The
logical name of the instance identifies the physical interface.
5.3.4.2 Other data link layers
Other media specific data link layers are defined in Annexes.
5.4 Service mapping and adaptation layers
5.4.1 For the default HDLC based data link layer
The application layer PDUs are transported by LLC frames through the LDTI interface as
specified in IEC 62056-46. The following restrictions apply for the default configuration:
• for the LLC sub-layer the format of IEC 62056-46: 2002, 5.3.2 is used;
• for the MAC sub-layer the frame format type 3 and the non-basic frame format is used by
default;
• the data link layer of the COSEM server acts as HDLC primary/control station using
unbalanced connectionless operation according to ISO/IEC 13239:2002, 6.13;
• the HDLC primary/control station sends unnumbered UI frames carrying the LLC frames;
• according to ISO/IEC 13239:2002, 6.13.4.2.1: whenever the HDLC primary/ control station
is ready to send an UI command frame it shall send it immediately since there is no flow
control in the connectionless class service. The tributary station(s) (data link layer of the
DLMS/COSEM client) shall only send UI response frames when given permission to do so;
• the LDTI transmission is unidirectional; therefore the HDLC primary/control station never
gives permission to the tributary station for UI responses.

5.4.2 For other lower layers
For lower layers not using the default HDLC data link layer the corresponding Annexes
describe the mapping of the services provided at the top end of the lower layers and lower
end of the DLMS/COSEM stack (application layer or, IPv4/IPv6 in the case of an IP based
stack).
5.5 Registration and connection management
There is no Application Service Element specified to manage the connection of the lower
communication layers.
6 Identification and addressing scheme
6.1 General identification and addressing scheme
To be able to exchange data via the lower layers, the client access points and the server
access points shall be identified and addressed according to the rules of the communication
profile.
The data defined in the attribute push_object_list of the “Push setup” instance is sent to the
interface as defined in the field destination (octet-string) of the send_destination_and_method
attribute. The meaning of the destination field depends on the type of transport_service used.
If several local LDTI interfaces need to be addressed then several instantiations of the class
“Push setup” are required. More details can be found in the Annexes of this standard.
A LDTI operating in the “legacy mode” is configured as described in Table 3.
6.2 Addressing for the default HDLC based data link layer
The data link layer addressing scheme is defined in IEC 62056-46: 2002, Clause 6.
6.3 Addressing for other data link layers
The identification and addressing schemes are defined in the media specific Annexes.
7 Specific considerations for the application layer services
7.1 Overview
The specific considerations for the application layer services take into account that the LDTI
is limited to one-way data transmission in a pre-established application association.
7.2 Application Association establishment and release: ACSE services
The LDTI client works in a pre-established application association. Therefore the ACSE
services are not supported; i.e. there are no AARQ and AARE APDUs exchanged via the
LDTI.
7.3 xDLMS services
The following xDLMS APDUs (see IEC 62056-5-3:2016, Clause 8) shall be supported to
operate the LDTI interface
• data-notification [15];
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• general-glo-ciphering [219] – if data protection is used;
• general-block-transfer [224] – if block transfer is used to handle long APDUs.
The LDTI association shall support the conformance block – see IEC 62056-5-3:2016, 7.3.1,
Table 39 – as shown in Table 2.
Table 2 – Conformance block for the LDTI association
reserved-zero (0) –
general-protection            (1) o
general-block-transfer          (2) o
read                   (3) –
write                   (4) –
unconfirmed-write            (5) –
reserved-six               (6) –
reserved-seven              (7) –
attribute0-supported-with-set   (8) –
priority-mgmt-supported        (9) –
attribute0-supported-with-get    (10) –
block-transfer-with-get-or-read    (11) –
block-transfer-with-set-or-write   (12) –
block-transf
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