IEC 61375-2-8:2021

Electronic railway equipment - Train communication network (TCN) - Part 2-8: TCN conformance test

IEC 61375-2-8:2021 applies to all equipment and devices implemented according to IEC 61375-2-3:2015, IEC 61375-2-5:2014 and IEC 61375-3-4:2014, i.e. it covers the procedures to be applied to such equipment and devices when the conformance should be proven. The applicability of this document to a TCN implementation allows for individual conformance checking of the implementation itself, and is a pre-requisite for further interoperability checking between different TCN implementations.

Matériel électronique ferroviaire - Réseau embarqué de train (TCN) - Partie 2-8: Essai de conformité TCN

IEC 61375-2-8:2021 s'applique à l'ensemble des équipements et dispositifs mis en œuvre conformément à l'IEC 61375-2-3:2015, l'IEC 61375-2-5:2014 et l'IEC 61375-3-4:2014, c'est-à-dire qu'elle couvre les modes opératoires à appliquer à ces équipements et dispositifs dont il convient de démontrer la conformité.

General Information

• Status: Published
• Publication Date: 24-Oct-2021
• ICS: 45.060.01 - Railway rolling stock in general
• Technical Committee: TC 9 - Electrical equipment and systems for railways
• Drafting Committee: WG 43 - TC 9/WG 43
• Current Stage: PPUB - Publication issued
• Start Date: 25-Oct-2021
• Completion Date: 05-Nov-2021

Overview

IEC 61375-2-8:2021 - "Electronic railway equipment - Train communication network (TCN) - Part 2‑8: TCN conformance test" defines the conformance test procedures for TCN equipment. It applies to devices implemented according to IEC 61375-2-3:2015, IEC 61375-2-5:2014 and IEC 61375-3-4:2014. The standard enables formal verification that an Item Under Test (IUT) meets protocol, interface and behaviour requirements, which is a pre‑requisite for interoperability between different TCN implementations.

Key Topics and Requirements

• Conformance approach and boundaries: Defines how conformance testing is scoped, including test categories (basic interconnection, capability, behaviour, and conformance resolution tests) and the mapping of IUT types to test suites.
• PICS pro‑forma: Use of Protocol Implementation Conformance Statements (PICS) to declare IUT capabilities and guide test applicability.
• Basic interface and physical layer tests: Inspection and electrical/physical checks for Ethernet interfaces, waveform and auto‑sensing/crossover behavior.
• Communication protocol tests: Simple UDP/TCP payload tests and long‑term reliability checks to validate protocol handling by End Devices.
• Communication reliability and robustness: Burst immunity, interface isolation and other resilience tests for stable operation under adverse conditions.
• Test suites for device classes: Extensive, structured test cases for:
  • End Devices (IEC 61375-2-3, -2-5, -3-4 related test cases)
  • ECN‑equipped consists (switch management, priority levels, rate limiting, VLAN/tagging, DHCP, DNS, NTP, SNMP)
  • ETBN (Ethernet Train Backbone Network) functions (link aggregation, TTDP/HELLO, TOPOLOGY frames, unicast/multicast forwarding)
• Management and service interfaces: Tests include DHCP address assignment, DNS/TCN‑URI resolution, SNMP/network management, switch management and optional interfaces (ECSP, TTDB manager, ETBN control).
• Conformance assessment process: Criteria for verdicts, analysis of results, and relation to interoperability and performance testing.

Practical Applications and Who Uses It

• Railway equipment manufacturers - validate that TCN hardware and software implementations conform to IEC TCN specifications before product release.
• Independent test laboratories and certification bodies - execute standardized test suites and PICS-based conformance assessments.
• System integrators and operators - confirm that components will interoperate reliably on train networks (ECN and ETBN).
• Network and firmware engineers - use the test definitions to design robust Ethernet-based TCN products (switches, end devices, backbone elements).

Related Standards

• IEC 61375-2-3:2015 (End Device definitions)
• IEC 61375-2-5:2014
• IEC 61375-3-4:2014
• IEEE Ethernet standards (referenced for waveform and electrical tests)

Keywords: IEC 61375-2-8, TCN conformance test, Train Communication Network, railway Ethernet testing, TCN interoperability, ECN, ETBN, PICS, DHCP, DNS, SNMP, NTP, multicast, link aggregation.

Standards Content (Sample)

IEC 61375-2-8 ®
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
colour
inside
Electronic railway equipment – Train communication network (TCN) –
Part 2-8: TCN conformance test
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC online collection - oc.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 000 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 18 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: [e-mail].
IEC 61375-2-8 ®
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
colour
inside
Electronic railway equipment – Train communication network (TCN) –

Part 2-8: TCN conformance test

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 45.060.01 ISBN 978-2-8322-1035-5

– 2 – IEC 61375-2-8:2021 © IEC 2021
CONTENTS
FOREWORD . 14
INTRODUCTION . 16
1 Scope . 17
2 Normative references . 17
3 Terms, definitions, symbols and abbreviated terms . 19
3.1 Terms and definitions . 19
3.2 Symbols and abbreviated terms . 19
4 Conformance test: approach, requirements and boundaries . 20
4.1 Approach . 20
4.1.1 General . 20
4.1.2 Requirements . 20
4.1.3 Requirements declaration statements for an Item Under Test (IUT) . 22
4.2 Boundaries . 23
4.2.1 General . 23
4.2.2 Basic interconnection tests . 24
4.2.3 Capability tests . 24
4.2.4 Behaviour tests . 25
4.2.5 Conformance resolution tests . 25
4.2.6 Interpretation of clauses/subclauses and statements . 26
4.2.7 Relation to interoperability . 27
4.2.8 Relation to performance test . 28
4.2.9 Definition of test cases . 28
4.3 Conformance assessment process outline . 29
4.3.1 General . 29
4.3.2 Analysis of results, outcomes and verdicts . 29
4.4 Mapping of IUT types to conformance test suites . 30
5 Basic interface test . 31
5.1 Scope . 31
5.2 PICS pro-forma . 31
5.2.1 General . 31
5.2.2 PICS Tables . 31
5.3 Testing framework . 33
5.4 Physical layer test . 33
5.4.1 Test purpose . 33
5.4.2 Inspection of the Hardware Ethernet interface . 33
5.4.3 Inspection of the mechanical Ethernet interface construction . 33
5.4.4 Check of electrical Ethernet interface design . 34
5.4.5 Check of Ethernet interface characteristics . 34
5.4.6 Ethernet signal wave form test (IEEE standard) . 34
5.4.7 Ethernet signal wave form test (amplified signals, optional) . 34
5.4.8 Auto-Crossover- and Auto-Sensing-Test (only for switches) . 34
5.5 Basic communication protocol test . 35
5.5.1 Test purpose . 35
5.5.2 Simple communication test . 35
5.5.3 UDP rising payload test (only for End Devices) . 35
5.5.4 TCP rising payload test (only for End Devices) . 35

5.5.5 UDP long term test (only for End Devices) . 35
5.6 Communication reliability tests . 35
5.6.1 Test purpose . 35
5.6.2 Burst immunity test . 35
5.6.3 Ethernet interface isolation test . 36
6 Conformance test of End Device . 36
6.1 General . 36
6.2 Related requirements . 37
6.3 IUT and Test scope . 37
6.4 PICS Pro-forma . 38
6.4.1 General . 38
6.4.2 PICS Tables . 38
6.5 Testing framework . 44
6.6 Test Suite IEC 61375-2-3 . 46
6.6.1 Test case TCCT23ED_001 . 46
6.6.2 Test case TCCT23ED_002 . 47
6.6.3 Test case TCCT23ED_003 . 49
6.6.4 Test case TCCT23ED_004 . 50
6.6.5 Test case TCCT23ED_005 . 51
6.6.6 Test case TCCT23ED_006 . 52
6.6.7 Test case TCCT23ED_007 . 53
6.6.8 Test case TCCT23ED_008 . 54
6.6.9 Test case TCCT23ED_009 . 55
6.7 Test Suite IEC 61375-2-5 . 55
6.7.1 Test case TCCT25ED_001 . 55
6.7.2 Test case TCCT25ED_002 . 56
6.7.3 Test case TCCT25ED_003 . 57
6.7.4 Test case TCCT25ED_004 . 58
6.7.5 Test case TCCT25ED_005 . 59
6.7.6 Test case TCCT25ED_006 . 60
6.7.7 Test case TCCT25ED_007 . 61
6.7.8 Test case TCCT25ED_008 . 62
6.7.9 Test case TCCT25ED_009 . 63
6.7.10 Test case TCCT25ED_010 . 64
6.8 Test Suite IEC61375-3-4 . 65
6.8.1 Test case TCCT34ED_001 . 65
6.8.2 Test case TCCT34ED_002 . 66
6.8.3 Test case TCCT34ED_003 . 67
6.8.4 Test case TCCT34ED_004 . 68
6.8.5 Test case TCCT34ED_005 . 69
6.8.6 Test case TCCT34ED_006 . 70
6.8.7 Test case TCCT34ED_007 . 71
6.8.8 Test case TCCT34ED_008 . 72
6.8.9 Test case TCCT34ED_009 . 73
6.8.10 Test case TCCT34ED_010 . 74
6.8.11 Test case TCCT34ED_011 . 75
6.8.12 Test case TCCT34ED_012 . 76
6.8.13 Test case TCCT34ED_013 . 77
6.8.14 Test case TCCT34ED_014 . 78

– 4 – IEC 61375-2-8:2021 © IEC 2021
6.8.15 Test case TCCT34ED_015 . 79
6.8.16 Test case TCCT34ED_016 . 80
6.8.17 Test case TCCT34ED_017 . 81
6.8.18 Test case TCCT34ED_018 . 82
6.8.19 Test case TCCT34ED_019 . 83
6.8.20 Test case TCCT34ED_020 . 84
6.8.21 Test case TCCT34ED_021 . 85
6.8.22 Test caseTCCT34ED_022 . 86
7 Conformance test of ECN-equipped consist . 86
7.1 Scope . 86
7.2 Related requirements . 86
7.3 PICS Pro-forma . 86
7.3.1 General . 86
7.3.2 PICS tables . 87
7.4 Test cases . 93
7.4.1 General . 93
7.4.2 Recovery in case of network failure . 94
7.4.3 IP address assignment via DHCP . 96
7.4.4 Name (TCN-URI address) resolution via DNS . 97
7.4.5 Switch basic functions . 98
7.4.6 Priority levels . 99
7.4.7 Ingress rate limiting . 99
7.4.8 Egress rate shaping . 100
7.4.9 Untagged/tagged frames. 100
7.4.10 Switching and routing performance (optional) . 101
7.4.11 NTP support . 102
7.4.12 Switch management . 102
7.4.13 Network management via SNMP . 103
7.4.14 ECSP Interface (optional) . 104
7.4.15 TTDB manager interface (optional) . 105
7.4.16 DNS TCN interface (optional) . 105
7.4.17 ETBN control interface (optional) . 106
8 Conformance test of ETBN . 106
8.1 Test scope . 106
8.1.1 General . 106
8.1.2 References . 106
8.2 PICS Pro-forma . 107
8.2.1 General . 107
8.2.2 PICS tables . 107
8.3 Test cases . 115
8.3.1 Testing framework . 115
8.3.2 Common Consist Topologies . 118
8.3.3 Test Suite: ETB port settings . 121
8.3.4 Test Suite: ETB Line Status and Link Aggregation management . 123
8.3.5 Test Suite: TTDP HELLO format and content . 130
8.3.6 Test Suite: Unicast address assignment and unicast routing . 134
8.3.7 Test Suite: IP Multicast forwarding. 137
8.3.8 Test Suite: TOPOLOGY frame format and basic functionality . 148
8.3.9 Test Suite: Physical topology management and calculation . 152

8.3.10 Test Suite: Logical connectivity management and calculation . 156
8.3.11 Test Suite: Failing/loss of node(s) . 162
8.3.12 Test Suite: Late/recovered node(s) . 166
9 Conformance test of TRDP . 172
9.1 General . 172
9.2 Related requirements . 173
9.3 SUT and Test scope . 173
9.4 PICS Pro-forma . 173
9.4.1 General . 173
9.4.2 PICS Tables . 173
9.5 Message Data test . 187
9.5.1 Testing framework . 187
9.5.2 Communication Model Test . 188
9.5.3 Communication Pattern and Addressing Test . 192
9.5.4 MD-PDU Test . 204
9.5.5 TRDP Layer Service Primitives Test . 206
9.5.6 TRDP Layer Filtering Rules Test. 209
9.5.7 Caller TRDP Layer Test . 214
9.5.8 Replier TRDP Layer Test . 234
9.5.9 TCP Connection Handling Test . 249
9.5.10 Message Data Echo Server Test . 257
9.6 Process Data test . 258
9.6.1 General . 258
9.6.2 Test setup . 258
9.6.3 PD push pattern test cases . 259
9.6.4 PD pull pattern test cases . 280
10 SDTv2 Conformance Test . 298
10.1 Scope . 298
10.1.1 General . 298
10.1.2 Related requirements . 298
10.1.3 Terms and abbreviations . 298
10.1.4 Test scope . 298
10.2 PICS Pro-forma . 299
10.2.1 General . 299
10.2.2 PICS Tables . 299
10.3 SDSRC- SAFE DATA SOURCE . 302
10.3.1 Purpose . 302
10.3.2 Inspection of the SID Structure . 302
10.3.3 Inspection of the Vital Data Packet . 303
10.3.4 Exclusivity . 304
10.3.5 SDSRC performance . 305
10.4 SDSINK – SAFE DATA SINK . 305
10.4.1 General . 305
10.4.2 VDP sampling . 305
10.4.3 VDP Integrity Check . 305
10.4.4 Sink Time Supervision . 306
10.4.5 Guard Time Supervision . 306
10.4.6 Latency Monitoring . 306
10.4.7 Channel Monitoring. 307

– 6 – IEC 61375-2-8:2021 © IEC 2021
10.4.8 SDTv2 Application Interface . 307
10.4.9 Diagnostics and statistics . 308
11 Conformance test of ETB-equipped consist . 308
11.1 Scope . 308
11.2 Abstract consist tester architecture . 309
11.3 Consist test stages . 311
11.4 PICS Pro-forma . 311
11.4.1 General . 311
11.4.2 PICS Tables . 311
11.5 Related requirements . 314
11.6 Testing configurations . 314
11.6.1 General . 314
11.6.2 Testing configuration TC1 . 315
11.6.3 Testing configuration TC2 . 316
11.6.4 Testing configuration TC3 . 316
11.7 Consist tester operation . 317
11.7.1 General . 317
11.7.2 ECS addressing . 317
11.7.3 Test Stimuli . 317
11.7.4 Expected result verification . 320
11.7.5 Test execution timing considerations . 321
11.8 Basic test . 321
11.8.1 General . 321
11.8.2 Test sequence for TTDB computation (middle consist, same orientation) . 321
11.8.3 Test sequence for TTDB computation (middle consist, inverse
orientation) . 321
11.8.4 Test sequence for TTDB computation (end consist, no traction, same

orientation) . 322
11.8.5 Test sequence for TTDB computation (end consist, no traction, inverse
orientation) . 322
11.8.6 Test sequence for TTDB computation (end consist, traction, same
orientation) . 323
11.8.7 Test sequence for TTDB computation (end consist, traction, inverse

orientation) . 323
11.8.8 Test sequence for TTDB computation (train lengthening and shortening) . 324
11.9 Leading test . 325
11.9.1 General . 325
11.9.2 Test sequence for Leading (TE1.1 leading, CuT middle) . 326
11.9.3 Test sequence for Leading (TE2 leading, CuT middle) . 326
11.9.4 Test sequence for Leading (TE1.1 leading, CuT end) . 326
11.9.5 Test sequence for Leading (CuT leading direction 1) . 327
11.9.6 Test sequence for Leading (CuT leading direction 2) . 327
11.9.7 Test sequence for Leading (Leading double request) . 328
11.9.8 Test sequence for Leading (Leading conflict) . 329
11.10 Inhibit test . 329
11.10.1 General . 329
11.10.2 Test sequence for Inhibit (single) . 329
11.10.3 Test sequence for Inhibit (multiple) . 330
11.11 Confirmation/correction test . 331
11.11.1 General . 331

11.11.2 Test sequence for confirmation . 332
11.11.3 Test sequence for correction single middle vehicle . 333
11.11.4 Test sequence for correction two middle vehicles . 333
11.11.5 Test sequence for correcting three middle vehicles . 334
11.11.6 Test sequence for correcting end vehicle . 335
11.12 Sleep mode function (optional) . 336
11.12.1 General . 336
11.12.2 Test sequence for sleep mode . 336
11.13 Performance test . 337
11.13.1 General . 337
11.13.2 Inauguration performance . 337
11.13.3 ECSP performance . 338
11.14 End-to-End Communication . 339
11.15 Multiple ETB test (option) . 339
11.15.1 General . 339
11.15.2 Conformance test . 340
Annex A (normative) Test laboratory role and client role . 341
A.1 Test laboratory and client role . 341
A.1.1 General . 341
A.1.2 Overview . 341
A.2 Preparation for testing . 342
A.2.1 General . 342
A.2.2 General administrative steps . 342
A.2.3 Agreement on test methods and selection of test suites . 342
A.2.4 Exchange of documentation for conformance assessment . 343
A.3 Test operation . 344
A.3.1 General . 344
A.3.2 Static conformance review . 344
A.3.3 Selection of test cases and test parameterisation . 345
A.3.4 Test campaign . 345
A.4 Production of test reports . 346
A.4.1 General . 346
A.4.2 IUT conformance test report . 347
A.4.3 Protocol conformance test report . 347
Annex B (informative) Instructions for filling the PICS pro-forma . 349
B.1 General . 349
B.2 Abbreviations . 349
B.3 Reference column . 349
B.4 Supported subclause column . 350
B.5 Supported capability column . 350
B.6 Requirement column . 350
B.7 Implementation column . 350
B.8 Parameter values columns . 351
B.8.1 Allowed min. . 351
B.8.2 Default value . 351
B.8.3 Allowed max. . 351
B.8.4 Implemented value . 351
Annex C (informative) Test instrumentation and dedicated test bed . 352
C.1 Test instrumentation . 352

– 8 – IEC 61375-2-8:2021 © IEC 2021
C.1.1 Standard instrumentation – Test suites standard instrumentation. 352
C.1.2 Test bed architecture . 352
C.1.3 Consist tester specification . 353
Bibliography . 356

Figure 1 – Setup for burst immunity test . 36
Figure 2 – End Device conformance testing process . 37
Figure 3 – Consist topology and logical view of ECN. 38
Figure 4 – Testing framework architecture . 44
Figure 5 – General configuration for ECN-equipped consist test . 94
Figure 6 – Example of configuration for the test of network redundancy . 94
Figure 7 – Example of configuration of network redundancy with dual homing End
Device interfaces . 95
Figure 8 – Example of the configuration for the test of IP address assignment via
DHCP . 97
Figure 9 – Example of the configuration for the test of Name resolution via DNS . 98
Figure 10 – Example of the configuration for the test of NTP support . 102
Figure 11 – Example of the configuration for the test of Network management via
SNMP . 104
Figure 12 – TTS1 One ETBN connects with test system (monitoring) . 116
Figure 13 – TTS2 single ETBN connects with test system (one side simulation) . 116
Figure 14 – TTS3 Single ETBN connects with test system (both sides simulation) . 117
Figure 15 – TTS4 Multiple ETBNs connect with test system (monitoring) . 117
Figure 16 – TTS5 multiple ETBNs connect with test system (one side simulation) . 118
Figure 17 – TTS6 Multiple ETBN connects with test system (both sides simulation) . 118
Figure 18 – Consist topology with single ETBN and single CN . 119
Figure 19 – Consist topology with multiple ETBNs, each connected to a separate CN . 119
Figure 20 – Consist topology with a single ETBN connected to multiple CNs . 119
Figure 21 – Consist topology with single CN with redundant ETBNs . 120
Figure 22 – Consist topology with multiple CNs with redundant ETBNs . 120
Figure 23 – Consist topology with multiple ETNs and CNs connected asymmetrically . 120
Figure 24 – Setup to verify full duplex mode on ETB ports . 122
Figure 25 – Example where IUT sends TOPOLOGY on line B (here X is B, Y is A) . 124
Figure 26 – Simulating Logical line down for single line setup, by letting simulator stop
sending HELLO on line X (line A) . 125
Figure 27 – Simulating Logical line down for multiple line setup, by letting simulator
stop sending HELLO on line X (here line B) . 125
Figure 28 – Simulating one-way transmission error, by letting simulator send HELLO
with recvXStatus FALSE (here recvBStatus FALSE) . 126
Figure 29 – Testing correct handling of loss of HELLO transmitted by IUT, and loss of
HELLO sent to IUT . 127
Figure 30 – ETB line failover setup, the line where IUT initially forwards the data
stream is referred to as ‘X’ (here line B) . 128
Figure 31 – Topology for general multicast routing tests . 138
Figure 32 – Topology for testing multicast with ETBN with multiple CNs . 140
Figure 33 – Multicast test setup for consist with ECNs connected to different ETBNs . 141

Figure 34 – Testing multicast with redundant ETBNs and single CN . 142
Figure 35 – Multicast routing in consist with redundant ETBN and multiple CNs . 144
Figure 36 – Testing multicast handling after reinauguation . 145
Figure 37 – Test of multicast between local CNs on same ETBN when inaugurating . 146
Figure 38 – Test of multicast between local CNs on different ETBNs when inaugurating . 147
Figure 39 – Test ability to translate multicast destination address . 147
Figure 40 – Testing transmission of connectivity vector . 154
Figure 41 – Testing transmission of ETBN Vectors, number of ETBNs and
ConnTableCrc32 . 155
Figure 42 – Testing loss of intermediate ETBNs/consists when inauguration is inhibited . 162
Figure 43 – Test of losing intermediate ETBN in existence of "unknown intermediate" . 163
Figure 44 – Test ability to handle loss of end node . 164
Figure 45 – Test ability to handle loss of end node during lengthening . 165
Figure 46 – Test ability to handle loss of end node when “late intermediate” is present . 166
Figure 47 – Test environment . 172
Figure 48 – System under Test . 173
Figure 49 – TTS, IUT connected to the test system . 259
Figure 50 – The switch in test topology . 259
Figure 51 – TRDP telegram format . 260
Figure 52 – Dataset of CONFTEST_PUSH_FORMAT . 261
Figure 53 – Dataset of CONFTEST_UDP_PORT . 262
Figure 54 – Dataset of CONFTEST_FCS . 264
Figure 55 – Dataset of CONFTEST_FCS_REPLY . 264
Figure 56 – Dataset of CONFTEST_PROTO_VERSION .
...

IEC 61375-2-8 ®
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electronic railway equipment – Train communication network (TCN) –
Part 2-8: TCN conformance test

Matériel électronique ferroviaire – Réseau embarqué de train (TCN) –
Partie 2-8: Essai de conformité TCN
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 19 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC -  IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications IEC gratuitement tous les aperçus des publications. Avec un
en utilisant différents critères (numéro de référence, texte, abonnement, vous aurez toujours accès à un contenu à jour
comité d’études, …). Elle donne aussi des informations sur les adapté à vos besoins.
projets et les publications remplacées ou retirées.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
Le premier dictionnaire d'électrotechnologie en ligne au monde,
Restez informé sur les nouvelles publications IEC. Just
avec plus de 22 300 articles terminologiques en anglais et en
Published détaille les nouvelles publications parues.
français, ainsi que les termes équivalents dans 19 langues
Disponible en ligne et une fois par mois par email.
additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc

Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[e-mail].
IEC 61375-2-8 ®
Edition 1.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electronic railway equipment – Train communication network (TCN) –

Part 2-8: TCN conformance test

Matériel électronique ferroviaire – Réseau embarqué de train (TCN) –

Partie 2-8: Essai de conformité TCN

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01  ISBN 978-2-8322-7440-8

– 2 – IEC 61375-2-8:2021 © IEC 2021
CONTENTS
FOREWORD . 14
INTRODUCTION . 16
1 Scope . 17
2 Normative references . 17
3 Terms, definitions, symbols and abbreviated terms . 19
3.1 Terms and definitions . 19
3.2 Symbols and abbreviated terms . 19
4 Conformance test: approach, requirements and boundaries . 20
4.1 Approach . 20
4.1.1 General . 20
4.1.2 Requirements . 20
4.1.3 Requirements declaration statements for an Item Under Test (IUT) . 22
4.2 Boundaries . 23
4.2.1 General . 23
4.2.2 Basic interconnection tests . 24
4.2.3 Capability tests . 24
4.2.4 Behaviour tests . 25
4.2.5 Conformance resolution tests . 25
4.2.6 Interpretation of clauses/subclauses and statements . 26
4.2.7 Relation to interoperability . 27
4.2.8 Relation to performance test . 28
4.2.9 Definition of test cases . 28
4.3 Conformance assessment process outline . 29
4.3.1 General . 29
4.3.2 Analysis of results, outcomes and verdicts . 29
4.4 Mapping of IUT types to conformance test suites . 30
5 Basic interface test . 31
5.1 Scope . 31
5.2 PICS pro-forma . 31
5.2.1 General . 31
5.2.2 PICS Tables . 31
5.3 Testing framework . 33
5.4 Physical layer test . 33
5.4.1 Test purpose . 33
5.4.2 Inspection of the Hardware Ethernet interface . 33
5.4.3 Inspection of the mechanical Ethernet interface construction . 33
5.4.4 Check of electrical Ethernet interface design . 34
5.4.5 Check of Ethernet interface characteristics . 34
5.4.6 Ethernet signal wave form test (IEEE standard) . 34
5.4.7 Ethernet signal wave form test (amplified signals, optional) . 34
5.4.8 Auto-Crossover- and Auto-Sensing-Test (only for switches) . 34
5.5 Basic communication protocol test . 35
5.5.1 Test purpose . 35
5.5.2 Simple communication test . 35
5.5.3 UDP rising payload test (only for End Devices) . 35
5.5.4 TCP rising payload test (only for End Devices) . 35

5.5.5 UDP long term test (only for End Devices) . 35
5.6 Communication reliability tests . 35
5.6.1 Test purpose . 35
5.6.2 Burst immunity test . 35
5.6.3 Ethernet interface isolation test . 36
6 Conformance test of End Device . 36
6.1 General . 36
6.2 Related requirements . 37
6.3 IUT and Test scope . 37
6.4 PICS Pro-forma . 38
6.4.1 General . 38
6.4.2 PICS Tables . 38
6.5 Testing framework . 44
6.6 Test Suite IEC 61375-2-3 . 46
6.6.1 Test case TCCT23ED_001 . 46
6.6.2 Test case TCCT23ED_002 . 47
6.6.3 Test case TCCT23ED_003 . 49
6.6.4 Test case TCCT23ED_004 . 50
6.6.5 Test case TCCT23ED_005 . 51
6.6.6 Test case TCCT23ED_006 . 52
6.6.7 Test case TCCT23ED_007 . 53
6.6.8 Test case TCCT23ED_008 . 54
6.6.9 Test case TCCT23ED_009 . 55
6.7 Test Suite IEC 61375-2-5 . 55
6.7.1 Test case TCCT25ED_001 . 55
6.7.2 Test case TCCT25ED_002 . 56
6.7.3 Test case TCCT25ED_003 . 57
6.7.4 Test case TCCT25ED_004 . 58
6.7.5 Test case TCCT25ED_005 . 59
6.7.6 Test case TCCT25ED_006 . 60
6.7.7 Test case TCCT25ED_007 . 61
6.7.8 Test case TCCT25ED_008 . 62
6.7.9 Test case TCCT25ED_009 . 63
6.7.10 Test case TCCT25ED_010 . 64
6.8 Test Suite IEC61375-3-4 . 65
6.8.1 Test case TCCT34ED_001 . 65
6.8.2 Test case TCCT34ED_002 . 66
6.8.3 Test case TCCT34ED_003 . 67
6.8.4 Test case TCCT34ED_004 . 68
6.8.5 Test case TCCT34ED_005 . 69
6.8.6 Test case TCCT34ED_006 . 70
6.8.7 Test case TCCT34ED_007 . 71
6.8.8 Test case TCCT34ED_008 . 72
6.8.9 Test case TCCT34ED_009 . 73
6.8.10 Test case TCCT34ED_010 . 74
6.8.11 Test case TCCT34ED_011 . 75
6.8.12 Test case TCCT34ED_012 . 76
6.8.13 Test case TCCT34ED_013 . 77
6.8.14 Test case TCCT34ED_014 . 78

– 4 – IEC 61375-2-8:2021 © IEC 2021
6.8.15 Test case TCCT34ED_015 . 79
6.8.16 Test case TCCT34ED_016 . 80
6.8.17 Test case TCCT34ED_017 . 81
6.8.18 Test case TCCT34ED_018 . 82
6.8.19 Test case TCCT34ED_019 . 83
6.8.20 Test case TCCT34ED_020 . 84
6.8.21 Test case TCCT34ED_021 . 85
6.8.22 Test caseTCCT34ED_022 . 86
7 Conformance test of ECN-equipped consist . 86
7.1 Scope . 86
7.2 Related requirements . 86
7.3 PICS Pro-forma . 86
7.3.1 General . 86
7.3.2 PICS tables . 87
7.4 Test cases . 93
7.4.1 General . 93
7.4.2 Recovery in case of network failure . 94
7.4.3 IP address assignment via DHCP . 96
7.4.4 Name (TCN-URI address) resolution via DNS . 97
7.4.5 Switch basic functions . 98
7.4.6 Priority levels . 99
7.4.7 Ingress rate limiting . 99
7.4.8 Egress rate shaping . 100
7.4.9 Untagged/tagged frames. 100
7.4.10 Switching and routing performance (optional) . 101
7.4.11 NTP support . 102
7.4.12 Switch management . 102
7.4.13 Network management via SNMP . 103
7.4.14 ECSP Interface (optional) . 104
7.4.15 TTDB manager interface (optional) . 105
7.4.16 DNS TCN interface (optional) . 105
7.4.17 ETBN control interface (optional) . 106
8 Conformance test of ETBN . 106
8.1 Test scope . 106
8.1.1 General . 106
8.1.2 References . 106
8.2 PICS Pro-forma . 107
8.2.1 General . 107
8.2.2 PICS tables . 107
8.3 Test cases . 115
8.3.1 Testing framework . 115
8.3.2 Common Consist Topologies . 118
8.3.3 Test Suite: ETB port settings . 121
8.3.4 Test Suite: ETB Line Status and Link Aggregation management . 123
8.3.5 Test Suite: TTDP HELLO format and content . 130
8.3.6 Test Suite: Unicast address assignment and unicast routing . 134
8.3.7 Test Suite: IP Multicast forwarding. 137
8.3.8 Test Suite: TOPOLOGY frame format and basic functionality . 148
8.3.9 Test Suite: Physical topology management and calculation . 152

8.3.10 Test Suite: Logical connectivity management and calculation . 156
8.3.11 Test Suite: Failing/loss of node(s) . 162
8.3.12 Test Suite: Late/recovered node(s) . 166
9 Conformance test of TRDP . 172
9.1 General . 172
9.2 Related requirements . 173
9.3 SUT and Test scope . 173
9.4 PICS Pro-forma . 173
9.4.1 General . 173
9.4.2 PICS Tables . 173
9.5 Message Data test . 187
9.5.1 Testing framework . 187
9.5.2 Communication Model Test . 188
9.5.3 Communication Pattern and Addressing Test . 192
9.5.4 MD-PDU Test . 204
9.5.5 TRDP Layer Service Primitives Test . 206
9.5.6 TRDP Layer Filtering Rules Test. 209
9.5.7 Caller TRDP Layer Test . 214
9.5.8 Replier TRDP Layer Test . 234
9.5.9 TCP Connection Handling Test . 249
9.5.10 Message Data Echo Server Test . 257
9.6 Process Data test . 258
9.6.1 General . 258
9.6.2 Test setup . 258
9.6.3 PD push pattern test cases . 259
9.6.4 PD pull pattern test cases . 280
10 SDTv2 Conformance Test . 298
10.1 Scope . 298
10.1.1 General . 298
10.1.2 Related requirements . 298
10.1.3 Terms and abbreviations . 298
10.1.4 Test scope . 298
10.2 PICS Pro-forma . 299
10.2.1 General . 299
10.2.2 PICS Tables . 299
10.3 SDSRC- SAFE DATA SOURCE . 302
10.3.1 Purpose . 302
10.3.2 Inspection of the SID Structure . 302
10.3.3 Inspection of the Vital Data Packet . 303
10.3.4 Exclusivity . 304
10.3.5 SDSRC performance . 305
10.4 SDSINK – SAFE DATA SINK . 305
10.4.1 General . 305
10.4.2 VDP sampling . 305
10.4.3 VDP Integrity Check . 305
10.4.4 Sink Time Supervision . 306
10.4.5 Guard Time Supervision . 306
10.4.6 Latency Monitoring . 306
10.4.7 Channel Monitoring. 307

– 6 – IEC 61375-2-8:2021 © IEC 2021
10.4.8 SDTv2 Application Interface . 307
10.4.9 Diagnostics and statistics . 308
11 Conformance test of ETB-equipped consist . 308
11.1 Scope . 308
11.2 Abstract consist tester architecture . 309
11.3 Consist test stages . 311
11.4 PICS Pro-forma . 311
11.4.1 General . 311
11.4.2 PICS Tables . 311
11.5 Related requirements . 314
11.6 Testing configurations . 314
11.6.1 General . 314
11.6.2 Testing configuration TC1 . 315
11.6.3 Testing configuration TC2 . 316
11.6.4 Testing configuration TC3 . 316
11.7 Consist tester operation . 317
11.7.1 General . 317
11.7.2 ECS addressing . 317
11.7.3 Test Stimuli . 317
11.7.4 Expected result verification . 320
11.7.5 Test execution timing considerations . 321
11.8 Basic test . 321
11.8.1 General . 321
11.8.2 Test sequence for TTDB computation (middle consist, same orientation) . 321
11.8.3 Test sequence for TTDB computation (middle consist, inverse
orientation) . 321
11.8.4 Test sequence for TTDB computation (end consist, no traction, same

orientation) . 322
11.8.5 Test sequence for TTDB computation (end consist, no traction, inverse
orientation) . 322
11.8.6 Test sequence for TTDB computation (end consist, traction, same
orientation) . 323
11.8.7 Test sequence for TTDB computation (end consist, traction, inverse

orientation) . 323
11.8.8 Test sequence for TTDB computation (train lengthening and shortening) . 324
11.9 Leading test . 325
11.9.1 General . 325
11.9.2 Test sequence for Leading (TE1.1 leading, CuT middle) . 326
11.9.3 Test sequence for Leading (TE2 leading, CuT middle) . 326
11.9.4 Test sequence for Leading (TE1.1 leading, CuT end) . 326
11.9.5 Test sequence for Leading (CuT leading direction 1) . 327
11.9.6 Test sequence for Leading (CuT leading direction 2) . 327
11.9.7 Test sequence for Leading (Leading double request) . 328
11.9.8 Test sequence for Leading (Leading conflict) . 329
11.10 Inhibit test . 329
11.10.1 General . 329
11.10.2 Test sequence for Inhibit (single) . 329
11.10.3 Test sequence for Inhibit (multiple) . 330
11.11 Confirmation/correction test . 331
11.11.1 General . 331

11.11.2 Test sequence for confirmation . 332
11.11.3 Test sequence for correction single middle vehicle . 333
11.11.4 Test sequence for correction two middle vehicles . 333
11.11.5 Test sequence for correcting three middle vehicles . 334
11.11.6 Test sequence for correcting end vehicle . 335
11.12 Sleep mode function (optional) . 336
11.12.1 General . 336
11.12.2 Test sequence for sleep mode . 336
11.13 Performance test . 337
11.13.1 General . 337
11.13.2 Inauguration performance . 337
11.13.3 ECSP performance . 338
11.14 End-to-End Communication . 339
11.15 Multiple ETB test (option) . 339
11.15.1 General . 339
11.15.2 Conformance test . 340
Annex A (normative) Test laboratory role and client role . 341
A.1 Test laboratory and client role . 341
A.1.1 General . 341
A.1.2 Overview . 341
A.2 Preparation for testing . 342
A.2.1 General . 342
A.2.2 General administrative steps . 342
A.2.3 Agreement on test methods and selection of test suites . 342
A.2.4 Exchange of documentation for conformance assessment . 343
A.3 Test operation . 344
A.3.1 General . 344
A.3.2 Static conformance review . 344
A.3.3 Selection of test cases and test parameterisation . 345
A.3.4 Test campaign . 345
A.4 Production of test reports . 346
A.4.1 General . 346
A.4.2 IUT conformance test report . 347
A.4.3 Protocol conformance test report . 347
Annex B (informative) Instructions for filling the PICS pro-forma . 349
B.1 General . 349
B.2 Abbreviations . 349
B.3 Reference column . 349
B.4 Supported subclause column . 350
B.5 Supported capability column . 350
B.6 Requirement column . 350
B.7 Implementation column . 350
B.8 Parameter values columns . 351
B.8.1 Allowed min. . 351
B.8.2 Default value . 351
B.8.3 Allowed max. . 351
B.8.4 Implemented value . 351
Annex C (informative) Test instrumentation and dedicated test bed . 352
C.1 Test instrumentation . 352

– 8 – IEC 61375-2-8:2021 © IEC 2021
C.1.1 Standard instrumentation – Test suites standard instrumentation. 352
C.1.2 Test bed architecture . 352
C.1.3 Consist tester specification . 353
Bibliography . 356

Figure 1 – Setup for burst immunity test . 36
Figure 2 – End Device conformance testing process . 37
Figure 3 – Consist topology and logical view of ECN. 38
Figure 4 – Testing framework architecture . 44
Figure 5 – General configuration for ECN-equipped consist test . 94
Figure 6 – Example of configuration for the test of network redundancy . 94
Figure 7 – Example of configuration of network redundancy with dual homing End
Device interfaces . 95
Figure 8 – Example of the configuration for the test of IP address assignment via
DHCP . 97
Figure 9 – Example of the configuration for the test of Name resolution via DNS . 98
Figure 10 – Example of the configuration for the test of NTP support . 102
Figure 11 – Example of the configuration for the test of Network management via
SNMP . 104
Figure 12 – TTS1 One ETBN connects with test system (monitoring) . 116
Figure 13 – TTS2 single ETBN connects with test system (one side simulation) . 116
Figure 14 – TTS3 Single ETBN connects with test system (both sides simulation) . 117
Figure 15 – TTS4 Multiple ETBNs connect with test system (monitoring) . 117
Figure 16 – TTS5 multiple ETBNs connect with test system (one side simulation) . 118
Figure 17 – TTS6 Multiple ETBN connects with test system (both sides simulation) . 118
Figure 18 – Consist topology with single ETBN and single CN . 119
Figure 19 – Consist topology with multiple ETBNs, each connected to a separate CN . 119
Figure 20 – Consist topology with a single ETBN connected to multiple CNs . 119
Figure 21 – Consist topology with single CN with redundant ETBNs . 120
Figure 22 – Consist topology with multiple CNs with redundant ETBNs . 120
Figure 23 – Consist topology with multiple ETNs and CNs connected asymmetrically . 120
Figure 24 – Setup to verify full duplex mode on ETB ports . 122
Figure 25 – Example where IUT sends TOPOLOGY on line B (here X is B, Y is A) . 124
Figure 26 – Simulating Logical line down for single line setup, by letting simulator stop
sending HELLO on line X (line A) . 125
Figure 27 – Simulating Logical line down for multiple line setup, by letting simulator
stop sending HELLO on line X (here line B) . 125
Figure 28 – Simulating one-way transmission error, by letting simulator send HELLO
with recvXStatus FALSE (here recvBStatus FALSE) . 126
Figure 29 – Testing correct handling of loss of HELLO transmitted by IUT, and loss of
HELLO sent to IUT . 127
Figure 30 – ETB line failover setup, the line where IUT initially forwards the data
stream is referred to as ‘X’ (here line B) . 128
Figure 31 – Topology for general multicast routing tests . 138
Figure 32 – Topology for testing multicast with ETBN with multiple CNs .
...