EN 50463-4:2012

SLOVENSKI STANDARD
01-marec-2013
1DGRPHãþD
SIST EN 50463:2008
Železniške naprave - Merjenje energije na vlaku - 4. del: Komunikacija
Railway applications - Energy measurement on board trains - Part 4: Communication
Bahnanwendungen - Energiemessung auf Bahnfahrzeugen - Teil 4: Kommunikation
Applications ferroviaires - Mesure d'énergie à bord des trains - Partie 4: Communications
Ta slovenski standard je istoveten z: EN 50463-4:2012
ICS:
45.060.10 9OHþQDYR]LOD Tractive stock
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 50463-4
NORME EUROPÉENNE
December 2012
EUROPÄISCHE NORM
ICS 45.060.10 Supersedes EN 50463:2007 (partially)

English version
Railway applications -
Energy measurement on board trains -
Part 4: Communication
Applications ferroviaires -  Bahnanwendungen -
Mesure d'énergie à bord des trains - Energiemessung auf Bahnfahrzeugen -
Partie 4: Communications Teil 4: Kommunikation

This European Standard was approved by CENELEC on 2012-10-15. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the CEN-CENELEC Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the CEN-CENELEC Management Centre has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50463-4:2012 E
Contents
Foreword . 4
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviations . 8
3.1 Terms and definitions . 8
3.2 Abbreviations .12
4 Requirements .14
4.1 General .14
4.2 On board communication subsystem .14
4.3 On board to ground communication subsystem .20
4.4 Access security .20
5 Conformity assessment .21
5.1 General .21
5.2 PICS and PIXIT .21
5.3 Design review .22
5.4 Type test procedure .22
Annex A (normative) On board to ground communication preferred solution .26
A.1 Communication services .26
A.2 EMS data transfer .30
A.3 Access security .35
Annex B (informative) VEI–VMF/CMF to ECF interface implementation example.36
B.1 General .36
B.2 Payload format .36
B.3 Encryption .37
Annex C (informative) PICS structure and instruction .38
C.1 Structure .38
C.2 Instructions for completing the PICS pro-forma .38
C.3 PICS pro-forma examples .40
Annex D (informative) Access security .43
Annex ZZ (informative) Coverage of Essential Requirements of EU Directives .44
Bibliography .45

Figures
Figure 1 – EMS functional structure and dataflow diagram . 6
Figure 2 – Example of energy index value . 9
Figure 3 – Communication interface between function/sub-function .14
Figure 4 – EMS block diagram and interfaces .15
Figure 5 – On board to ground communication stack .20
Figure 6 – Test bench for on board interface .23
Figure 7 – On board to ground test bench 1 .24
Figure 8 – On board to ground test bench 2 .24
Figure A.1 – Communication components .26
Figure B.1 – Payload format .36

- 3 - EN 50463-4:2012
Tables
Table 1 – List of permitted protocol stacks .16
Table A.1 – Preferred solution communication services .29
Table A.2 – Preferred solution application services .30
Table A.3 – Record format .32
Table C.1 – PICS table format .38
Table C.2 – PICS identification table .40
Table C.3 – IUA identification table .41
Table C.4 – IUA supplier identification table .41
Table C.5 – Applicable standards identification table .42
Table C.6 – Global statement table .42
Table C.7 – Level of conformity .42

Foreword
This document (EN 50463-4:2012) has been prepared by CLC/TC9X "Electrical and electronic
applications for railways".
The following dates are proposed:
• latest date by which this document has to be
(dop) 2013-10-15
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards
(dow) 2015-10-15
conflicting with this document have to
be withdrawn
This document (EN 50463-4:2012), together with parts 1, 2, 3 and 5, supersedes EN 50463:2007.
 the series is based on and supersedes EN 50463:2007;
 the scope is extended, new requirements are introduced and conformity assessment
arrangements are added.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
This document has been prepared under a mandate given to CENELEC by the European Commission
and the European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive 2008/57/EC amended by Commission Directive 2011/18/EU, see
informative Annex ZZ, which is an integral part of this document.
This document is Part 4 of the EN 50463 series which consists of the following parts, under the title
Railway applications - Energy measurement on board trains:
Part 1, General;
Part 2, Energy measuring;
Part 3, Data handling;
Part 4, Communication;
Part 5, Conformity assessment.
This series of European Standards follows the functional guidelines description in Annex A “Principles
of conformity assessment” of EN ISO/IEC 17000 tailored to the Energy Measurement System (EMS).
The requirements for Energy Measurement Systems in the relevant Technical Specifications for
Interoperability are supported by this series of European Standards.

- 5 - EN 50463-4:2012
Introduction
The Energy Measurement System provides measurement and data suitable for billing and may also
be used for energy management, e.g. energy saving.
This series of European Standards uses the functional approach to describe the Energy Measurement
System. These functions are implemented in one or more physical devices. The user of this series of
standards is free to choose the physical implementation arrangements.
Structure and main contents of the EN 50463 series
This series of European Standards is divided into five parts. The titles and brief descriptions of each
part are given below:
EN 50463-1 – General
The scope of EN 50463-1 is the Energy Measurement System (EMS).
EN 50463-1 provides system level requirements for the complete EMS and common requirements for
all devices implementing one or more functions of the EMS.
EN 50463-2 – Energy measuring
The scope of EN 50463-2 is the Energy Measurement Function (EMF).
The EMF provides measurement of the consumed and regenerated active energy of a railway traction
unit. If the traction unit is designed for use on a.c. traction supply systems the EMF also provides
measurement of reactive energy. The EMF provides the measured quantities via an interface to the
Data Handling System.
The EMF consists of the three functions: Voltage Measurement Function, Current Measurement
Function and Energy Calculation Function. For each of these functions, accuracy classes are specified
and associated reference conditions are defined. EN 50463-2 also defines all specific requirements for
all functions of the EMF.
The Voltage Measurement Function measures the voltage of the Contact Line system and the Current
Measurement Function measures the current taken from and returned to the Contact Line system.
These functions provide signal inputs to the Energy Calculation Function.
The Energy Calculation Function inputs the signals from the Current and Voltage Measurement
Functions and calculates a set of values representing the consumed and regenerated energies. These
values are transferred to the Data Handling System and are used in the creation of Compiled Energy
Billing Data.
The standard has been developed taking into account that in some applications the EMF may be
subjected to legal metrological control. All relevant metrological aspects are covered in EN 50463-2.
EN 50463-2 also defines the conformity assessment of the EMF.
EN 50463-3 – Data handling
The scope of EN 50463-3 is the Data Handling System (DHS).
The on board DHS receives, produces and stores data, ready for transmission to any authorised
receiver of data on board or on ground. The main goal of the DHS is to produce Compiled Energy
Billing Data and transfer it to an on ground Data Collection Service (DCS). The DHS can support other
functionality on board or on ground with data, as long as this does not conflict with the main goal.
EN 50463-3 also defines the conformity assessment of the DHS.
EN 50463-4 – Communication
The scope of EN 50463-4 is the communication services.

This part of the EN 50463 gives requirements and guidance regarding the data communication
between the functions implemented within EMS as well as between such functions and other on board
units where data are exchanged using a communications protocol stack over a dedicated physical
interface or a shared network.
It includes the on board to ground communication service and covers the requirements necessary to
support data transfer between DHS and DCS.
EN 50463-4 also defines the conformity assessment of the communications services.
EN 50463-5 – Conformity assessment
The scope of EN 50463-5 is the conformity assessment procedures for the EMS.
EN 50463-5 also covers re-verification procedures and conformity assessment in the event of the
replacement of a device of the EMS.
EMS functional structure and dataflow
Figure 1 illustrates the functional structure of the EMS, the main sub-functions and the structure of the
dataflow and is informative only. Only the main interfaces required by this standard are displayed by
arrows.
Since the communication function is distributed throughout the EMS, it has been omitted for clarity.
Not all interfaces are shown.
Time Reference Source
Location Reference Source
Current Measurement Function
Voltage Measurement Function
Data
Data Handling System
Energy Calculation Function
Collection
Service
Energy Measurement Function Data Handling System
(DCS)
(EMF) (DHS)
EN 50463-2 (Energy Measuring) EN 50463-3 (Data Handling)
Energy Measurement System (EMS)
EN 50463-1 (General), EN 50463-4 (Communication), EN 50463-5 (Conformity Assessment)

On-board (Traction Unit)
On-ground
Figure 1 – EMS functional structure and dataflow diagram

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1 Scope
This European Standard applies to the on board and on board to ground communication services, i.e.
it covers the data communication using digital interfaces:
a) between functions implemented within the EMS;
b) between EMS function and other on board subsystems;
c) between EMS and ground communication services.
The on board data communication services of the EMS are covering the data exchange between
functions of the EMS and the data exchange between EMS and other on board units, where data is
exchanged using a communications protocol stack over a dedicated physical interface or a shared
communication network.
The on board to ground communication services are covering the wireless data communication
between the DHS and the on ground server.
Furthermore, this document includes conformity assessment requirements.
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.
EN 50463-1:2012, Railway applications — Energy measurement on board trains — Part 1: General
EN 50463-2:2012, Railway applications — Energy measurement on board trains — Part 2: Energy
measuring
EN 50463-3:2012, Railway applications — Energy measurement on board trains — Part 3: Data handling
EN 50463-5, Railway applications — Energy measurement on board trains — Part 5: Conformity
assessment
EN 60870-5 (all parts), Telecontrol equipment and systems — Part 5: Transmission protocols
(IEC 60870-5 series)
EN 61158-2, Industrial communication networks — Fieldbus specifications — Part 2: Physical layer
specification and service definition (IEC 61158-2)
IEC 61375 (all parts), Electronic railway equipment — Train communication network (TCN)
ISO 11898-1:2003, Road vehicles — Controller area network (CAN) — Part 1: Data link layer and
physical signalling
ISO 11898-2:2003, Road vehicles — Controller area network (CAN) — Part 2: High-speed medium
access unit
ISO/IEC 8482, Information technology — Telecommunications and information exchange between
systems — Twisted pair multipoint interconnections
ISO/IEC 8825 (all parts), Information technology — ASN.1 encoding rules
ISO/IEC 8802-3:2000, Information technology — Telecommunications and information exchange between
systems — Local and metropolitan area networks — Specific requirements — Part 3: Carrier sense
multiple access with collision detection (CSMA/CD) access method and physical layer specifications

ISO/IEC 9646-1:1994, Information technology — Open Systems Interconnection — Conformance
1)
testing methodology and framework — Part 1: General concepts
ITU-T Recommendation V.24, List of definitions for interchange circuits between data terminal
equipment (DTE) and data circuit-terminating equipment (DCE)
RFC 1035, Domain names: implementation and specification
RFC 1123, Requirements for Internet Hosts – Application and Support
RFC 1535, A Security Problem and Proposed Correction With Widely Deployed DNS Software
RFC 2181, Clarifications to the DNS specification
TIA/EIA-422-B, May 1994, Electrical Characteristics of Balanced Voltage Digital Interface Circuits
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 50463-1:2012 and the
following apply.
NOTE When possible, the following definitions have been taken from the relevant chapters of the International
Electrotechnical Vocabulary (IEV), IEC 60050. In such cases, the appropriate IEV reference is given. Certain new
definitions or modifications of IEV definitions have been added in this standard in order to facilitate understanding.
Expression of the performance of electrical and electronic measuring equipment has been taken from EN 60359.
3.1.1
Board to Ground Interface
BGI
interface used for the communication between the train and the ground
3.1.2
consist
single vehicle or group of vehicles that are not separated during normal operation; train set and rake of
coaches are synonyms
Note 1 to entry: A consist may contain one or more traction units.
3.1.3
consist network
CN
communication network interconnecting communication devices in one consist
Note 1 to entry: It is possible that more than one CN is installed in the same consist.
3.1.4
Consist Network Interface
CNI
interface to an on board consist network used by the EMS and by other on board devices interfacing
with the EMS
———————
1)
Also available as ITU-T Recommendation X.290 (04/95), OSI conformance testing methodology and framework for protocol
Recommendations for ITU-T applications – General concepts

- 9 - EN 50463-4:2012
3.1.5
Coordinated Universal Time
UTC
time scale which forms the basis of a coordinated radio dissemination of standard frequencies and
time signals; it corresponds exactly in rate with international atomic time, but differs from it by an
integral number of seconds
Note 1 to entry: Coordinated universal time is established by the International Bureau of Weights and Measures
(BIPM) and the International Earth Rotation Services (IERS).
Note 2 to entry: The UTC scales is adjusted by the insertion or deletion of seconds, so called positive or
negative leap seconds, to ensure approximate agreement with UT1.
[SOURCE: ITU-R Recommendation TF.686, modified]
3.1.6
DHS to Service Interface
DSI
interface between the DHS and a maintenance/administration tool
3.1.7
DHS to MCF Interface
DMI
interface between the DHS and the MCF; it may be dedicated or shared on CNI
3.1.8
EMF to DHS Interface
EMDI
interface between the EMF and the DHS
3.1.9
EMF to Service Interface
ESI
interface between the EMF and a maintenance/administration tool
3.1.10
energy delta value
energy consumed and/or regenerated during a time period
Note 1 to entry: See Figure 2 for example.
3.1.11
energy index value
total accumulated energy consumption and/or energy regeneration at the end of a time period
Note 1 to entry: See Figure 2 for example.
energy index value: 2350 2360 2372 2379 2393 2404
10 12 7 14 11
energy delta value:
Timeline:
10:35 10:40 10:45 10:50 10:55 11:00

Figure 2 – Example of energy index value

3.1.12
flag
code indicating information relevant to the functioning of the EMS
Note 1 to entry: Examples include data quality, operational status, etc.
3.1.13
Fully Qualified Domain Name
FQDN
domain name which specifies its exact location in the tree hierarchy of the Domain Name System
(DNS); it specifies all domain levels, starting from the host name up to the top-level domain
3.1.14
Ground Station
GS
any station on ground which is able to communicate with the EMS
Note 1 to entry: A GS may host different services such as DCS or any EMS management service.
3.1.15
integrity
security measures addressing the detection of a corrupted payload
3.1.16
Internet Engineering Task Force
IETF
organised activity of the Internet Society in charge of producing technical documents relevant to the
design, use and management of the Internet
3.1.17
Implementation Under Assessment
IUA
implementation of one or more protocols specified in this part of EN 50463 in an adjacent
user/provider relationship being a part of the EMS that is submitted to the conformity assessment
3.1.18
location data
data describing the geographical position of the traction unit
3.1.19
Location Function to DHS Interface
LFDI
interface linking the location function to the DHS
Note 1 to entry: The location function can be interfaced with the DHS via a CNI.
3.1.20
Mobile Communication Function
MCF
function performing the EMS to on ground communication
Note 1 to entry: It includes the sub-function(s) for the wireless link between the train and ground and the sub-
functions that execute the communication protocols up to the application interface.
3.1.21
Mobile Communication Gateway
MCG
device that implements the MCF
Note 1 to entry: It may be embedded into the DHS, shared on CNI or connected as a dedicated device by
means of the DMI.
- 11 - EN 50463-4:2012
3.1.22
non-voluntary change
accidental or unintentional change
Note 1 to entry: Accidental change is caused by unpredictable physical influences, and unintentional change is
the effect caused by user functions and residual defects of the software even though the best efforts in
development techniques have been applied.
3.1.23
payload
part of the message containing the useful data produced by the source application and used by the
destination application
3.1.24
Protocol Analyser
PA
instrument which is used to record and analyse the frames produced by the IUA during the protocol
testing
3.1.25
Protocol Frame Generator
PFG
instrument which is used to inject the testing frames into the interface of the IUA
3.1.26
Protocol Implementation Conformity Statement
PICS
document containing the information of the claim of conformity of the IUA in respect of the
specification
3.1.27
protective interface
interface which permits intended data to be exchanged, and prevents unintended data being
exchanged
3.1.28
Protocol Implementation Extra Information for Testing
PIXIT
document used when testing the user defined aspects of the protocol for the IUA
3.1.29
sensor
device performing the VMF and/or CMF
Note 1 to entry: Sensor is used as a general term and encompasses a wide variety of technology / devices for
measurement purposes e.g. inductive transformers, hall-effect devices, capacitive and resistive dividers, and
resistive shunts etc.
Note 2 to entry: One sensor can perform multiple functions.
3.1.30
software
executable code, databases, registers and any parameter that affect the software execution
3.1.31
test authority
organisation responsible for conformity testing
3.1.32
test bench
arrangement of test equipment for testing an IUA

Note 1 to entry: Test equipment may include oscilloscopes, signal generators and other instruments.
3.1.33
TGZ
file format and the name of a program used to handle such files
Note 1 to entry: The format was created in the early days of Unix and standardized by POSIX.1-1988 and later POSIX.1-
2001.
3.1.34
Time Reference Period
TRP
period of time for which CEBD is produced
3.1.35
Train Control and Monitoring System
TCMS
set of interrelated objects providing on board control and monitoring of the train
3.1.36
UNIX time
EPOCH
st
of January 1970 according to the Coordinated
number of seconds elapsed since midnight on the 1
Universal Time (UTC); coded as a signed integer data type of 32 bits
3.1.37
UTC source to DHS interface
TFDI
dedicated interface of the UTC Source to the DHS
Note 1 to entry: The UTC source can be interfaced with the DHS via a CNI.
3.1.38
verdict
statement of “pass”, “fail”, or “inconclusive”, as specified in an abstract test case, concerning
conformity of an IUA with respect to the test case when it is executed
3.1.39
VMF/CMF to ECF Interface
VEI
interface between a VMF/CMF and an ECF
Note 1 to entry: It may be a combined interface for VMF and CMF or two separated interfaces.
3.1.40
voluntary change
intentional change consisting in a modification of software elements and/or modification, loading or
swapping of the memory
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
All the abbreviations are listed in alphabetical order.
The definition of some of the abbreviations can be found in EN 50463-1:2012, Clause 3.
BGI Board to Ground Interface
CEBD Compiled Energy Billing Data
CMF Current Measurement Function
CNI Consist Network Interface
- 13 - EN 50463-4:2012
CPID Consumption Point ID
CRC Cyclic Redundancy Check
DCS Data Collection System
DHS Data Handling System
DMI DHS interface to Mobile Communication Function
DSI Data Handling System to service interface
ECF Energy Calculation Function
EMDI EMF to DHS interface
EMF Energy Measurement Function
EMS Energy Measurement System
EPOCH UNIX Time
ESI Energy Measuring Function to service interface
EVN European Vehicle Number
FQDN Fully Qualified Domain Name
GS Ground Station
IETF Internet Engineering Task Force
IUA Implementation Under Assessment
LFDI Location Function to DHS interface
MCF Mobile Communication Function
MCG Mobile Communication Gateway
NMEA National Marine Electronics Association
PA Protocol Analyser
PFG Protocol Frame Generator
PICS Protocol Implementation Conformity Statement
PIXIT Protocol Implementation Extra Information for Testing
RAMS Reliability, Availability, Maintainability and Safety
SNTP Simple Network Time Protocol
TCMS Train Control and Monitoring System
TFDI UTC Source to DHS interface
TRP Time Reference Period
UTC Coordinated Universal Time
VEI VMF/CMF to ECF interface
VMF Voltage Measurement Function

4 Requirements
4.1 General
The requirements in EN 50463-1:2012, Clause 4, apply to any device containing one or more
implementation of the Communication Services where applicable. EN 50463-4 defines additional
requirements specific to the Communication Services.
4.2 On board communication subsystem
4.2.1 General
Figure 3 describes the functional structure of the communication between two functions and/or sub-
functions. Embedded communication is implemented using a virtual channel and exposed
communication is implemented using physical channel. Whether the communication between
functions/sub-functions is performed by a virtual or a physical link, is an implementation choice.
Function /
Function /
Embedded
Sub-function B
Sub-function A
Communication
Behavioural
interface
Behavioural
specification
specification
To be implemented by a
virtual channel
Specified as the Syntax and
the semantics of the
exchanged data
Function/sub-function Function/sub-function
interface interface
Exposed
Communication
Interface
Protocols stack
Protocols stack
To be implemented by
Physical channel
(security)
(security)
Specified as protocols to
transfer the payload
Figure 3 – Communication interface between function/sub-function
The on board communication subsystem covers the specification of the communication protocol stack,
the communication security sub-function and the communication profile for digital interfaces where it is
implemented using an exposed communication interface over a physical channel. Figure 4 illustrates
some of the possible interfaces, noting that some of them may be combined or may be alternative.
Data transfer using an embedded communication interface, implemented using a virtual channel, is
specified elsewhere in the relevant part of this series of standards.
Figure 4 shows the EMS functions which communicate through interfaces. The BGI interface is
specified in 4.3.
- 15 - EN 50463-4:2012
Voltage and Current
Measurement
VEI VEI UTC
ESI
E
source
M
(Date/Time)
F
Energy Calculation
Other on-
Location
board
source
systems
(Long/Lat)
EMDI
Maintenance
tools
TFDI
D
LFDI
H Data Data
CNI
S Storage Handler
DSI
Maintenance
DMI
tools
MCF
BGI
on air
Key
BGI Board to Ground interface
CNI Consist Network interface between DHS and other on board subsystems
DMI interface between DHS and MCF
EMDI interface between EMF and DHS
ESI interface between EMF and the maintenance tools
DSI interface between DHS and the maintenance tools
LFDI interface between the DHS and location device
TFDI interface between the DHS and UTC source
VEI interface between VMF and/or CMF and ECF
Figure 4 – EMS block diagram and interfaces
ESI and DSI are exposed interfaces which are intended to be used for:
1) maintenance;
2) EMF and/or DHS administration;
3) testing.
More than one interface, dedicated to this purpose, may exist according to the structure of the EMS
implementation, e.g. if the EMF and DHS are implemented in two separate devices, it is possible to
implement one interface attached to EMF and one attached to DHS.
The interface LFDI is required if the data are exchanged between DHS and a dedicated location
function. Alternatively, the location function may be interfaced with the DHS via the CNI.
The interface TFDI is required if the data are exchanged between DHS and a dedicated UTC source
device. Alternatively, the UTC source may be interfaced with the DHS via the CNI.
The interface DMI is required if the data are exchanged between DHS and a dedicated Mobile
Communication Function. Alternatively, the Mobile Communication Function may be interfaced with
the DHS via the CNI.
The interface CNI is required if the data are exchanged between DHS and external TCMS subsystems
or non-embedded EMS function, e.g. TCMS subsystems attached to the consist network or location
device linked to DHS via the shared consist network.

4.2.2 Communication protocols stack
The communication protocol stack executed by each on board physical interface shall be one of those
listed in Table 1. A different protocol stack can be used for each interface.
If the protocol chosen from Table 1 is ‘user defined’, the IUA Supplier shall give the evidence that the
capabilities and performance characteristics are comparable with the ones provided by the protocols
listed in Table 1 and specified in the referenced standards. The capabilities and the performance
parameters shall be reported in the relevant PIXIT that shall be compiled by the IUA Supplier when the
IUA is submitted to the Conformity Assessment.
Table 1 – List of permitted protocol stacks
Protocol Physical layer Link layer Upper layer
stack
Reference standard Reference standard Reference standard
RS232 ITU-T Recommendation V.24 user defined. user defined
RS485 ISO/IEC 8482 EN 60870-5 (all parts) Application specific using
the following services:
S1 (send/no reply)
S2 (send/confirm)
S3 (request/respond)
RS422 TIA/EIA-422-B, May 1994 EN 60870-5 (all parts) Application specific using
the following services:
S1 (send/no reply)
S2 (send/confirm)
S3 (request/respond)
CANopen ISO 11898-2:2003 ISO 11898-1:2003 EN 61375-3-3
ETHERNET ISO/IEC 8802-3:2000 EN 61375-3-4 EN 61375-3-4
MVB EN 61375-3-1 EN 61375-3-1 EN 61375-3-1
FIP EN 61158-2 EN 61158-2 EN 61158-2
user defined user defined user defined user defined
NOTE 1 The USB is not listed because it is not specified by a standardisation body recognised by CENELEC.
Nevertheless, it may be possible to use it as user defined solution.
NOTE 2 The RS232 is listed but should be used with care because it is not sufficiently robust for the demanding
electromagnetic environment found typically on board of trains.

Irrespective of the chosen protocol and in order to execute the conformity Design Review and the
Conformity Test procedure, the IUA Supplier shall provide the PICS relevant to this protocols stack
and the mapping to the specifications stated in the clauses relevant to the design review and to the
Conformity module test procedure.
4.2.3 Communication security
4.2.3.1 General
4.2.3 specifies the requirements for achieving the proper level of communication security of the
interface. The communication security shall assure the integrity and authenticity of the exchanged
payload data.
Referring to integrity, it shall be assured that the risk of accepting exchanged information containing
unintentional or accidental changes and/or intentional changes is reduced to an acceptable level.
Referring to authenticity, it shall be assured that the risk of accepting exchanged data transmitted by a
wrong source function/sub-function and received by the wrong consumer function/sub-function is
reduced to an acceptable level.

- 17 - EN 50463-4:2012
In order to reach an acceptable level, two cases are considered:
1) data transfer is protected by physical means;
2) data transfer is protected by software means.
The protection by physical means is specified in EN 50463-1:2012, 4.3.5.1 and 4.3.5.2.
4.2.3.2 Security implemented by software
4.2.3.2.1 General
If the physical means cannot assure an adequate security level, the security shall be assured by a
dedicated software layer that shall be added to the communication protocol stack of the relevant
interface.
The protection by software shall respect the general requirements specified in EN 50463-1:2012,
4.3.4.2, 4.3.4.3, 4.3.4.4, 4.3.4.5 and 4.3.5.3.
The software security layer shall provide:
a) the data integrity at application level;
b) the authenticity to ensure data transfer over the interface only occurs between the correct devices.
This is optional if the requirement a) adequately covers the detection of data changes (caused by
intentional and unintentional actions).
NOTE Bounding is one method for ensuring authenticity.
When the secrecy of data is required by the purchaser and agreed with the supplier, the software
security layer may provide encryption of the transferred data.
4.2.3.2.2 Data integrity
The integrity of the data shall be assured by an error detecting code applied at application level on the
payload data.
The type of error detecting code and its length shall be chosen considering the payload length in order
to assure at a reasonable level that any change in the payload data is detected.
NOTE CRC is one method for communication error detecting.
4.2.3.2.3 Bounding procedure and data encryption
This clause is informative.
The bounding procedure is applied in order to generate a secret key that is transferred under
controlled condition between the two units that communicate throughout the interface. The key is
generated by the master unit and transferred in a controlled environment to the slave unit. This key is
used to encrypt the payload by the transmitting unit and to decrypt the payload extracted from the
received frame by the receiving unit.
This procedure is executed attaching the maintenance tool (e.g. a PC) to the maintenance interface of
the master unit and activating the procedure after a successful authentication based on User ID and
password owned only by the authorised personnel.
As soon as the bounding procedure is started, the following events occur.
a) The master unit generates a key and stores it in a dedicated memory cell that cannot be accessed
in the future except by the software that has to decrypt the payload.
b) The key is transmitted to the slave unit that stores it in a dedicated memory cell that cannot be
accessed in the future except by the software that has to encrypt the payload.

c) The encryption and decryption of a known payload is transmitted from the master unit to the slave
unit and vice-versa to check that the two are correctly bounded.
d) The procedure is closed.
4.2.4 VMF/CMF to ECF Interface (VEI)
If this interface is digital, it shall be implemented according to EN 50463-2:2012, 4.3 and 4.4, and the
requirements listed in this document under 4.2.2 and 4.2.3.
An example of implementation is given in informative Annex B.
NOTE VEI may be implemented as a shared interface like CNI provided that the performance, safety and
security level is adequate and comparable with the level of a direct and exclusive serial interface.

4.2.5 EMF to DHS interface (EMDI)
This shall be a protective interface.
This interface shall be implemented according to one of the following options:
a) a direct and exclusive serial interface between EMF and DHS;
b) a shared interface like CNI provided that the security level is adequate and comparable with
the level of a direct and exclusive serial interface.
The interface shall transfer at least the data in accordance with EN 50463-2 and EN 50463-3.
4.2.6 Maintenance/testing interfaces (DSI and ESI)
This shall be a protective interface.
This is a serial interface to be used by the tools dedicated to the EMS maintenance and testing.
If the EMF and DHS functions are implemented in a single device, at least one interface shall be
provided for the maintenance and testing purposes.
If the EMF and DHS functions are implemented in two separate devices, one of the two cases shall
apply:
Case 1: there is only one maintenance/testing interface that shall be controlled by the main
processing unit of the DHS. In this case, a software module, called the agent, is in charge of routing
the information relevant to the maintenance/testing of EMF through the EMDI interface invoking a
software module, called the manager, which is in charge of executing the maintenance/testing tasks in
the EMF.
Case 2: there are two interfaces dedicated to maintenance/testing, one attached to the device
implementing the DHS function and one attached to the device implementing the EMF function.
NOTE The above statements give maintenance/testing interfaces requirements when the implementation of an
EMS is done with multiple devices.
The access shall be controlled according to the requirements specified in EN 50463-1:2012, 4.3.2.1.3
and 4.3.2.2.
4.2.7 DHS to location function
Two interfaces are possible:
a) the LFDI interface;
- 19 - EN 50463-4:2012
b) the CNI interface that connects the DHS to the location function by means of the consist network
digital interface.
If the case a) applies, the interface shall be a direct and exclusive serial interface to the location
function.
If the case b) applies, requirements are given in 4.2.9.
The interface shall transfer location information in accordance with EN 50463-3:2012, 4.4.
If this interface is able to provide UTC information compliant to the specification given in
EN 50463-3:2012, 4.2, it can be used as UTC source interface.

4.2.8 DHS to UTC source
Two interfaces are possible:
a) the TFDI interface;
b) the CNI interface that connects the DHS to the UTC source by means of the consist network
digital interface.
If case a) applies, the interface shall be a direct and exclusive interface between a UTC source and
the DHS. No other on board subsystem shall be attached to this time function by any means or
interface
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