IEC 61375-1:2007

INTERNATIONAL IEC
STANDARD 61375-1
Second edition
2007-04
Electric railway equipment –
Train bus –
Part 1:
Train communication network
Reference number
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INTERNATIONAL IEC
STANDARD 61375-1
Second edition
2007-04
Electric railway equipment –
Train bus –
Part 1:
Train communication network
PRICE CODE
Commission Electrotechnique Internationale
XH
International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 61375-1 © IEC:2007(E)
CONTENTS
FOREWORD.13
INTRODUCTION.15

1 General .17
1.1 Scope.17
1.2 Normative references .17
1.3 Terms and definitions .18
1.4 Abbreviations.35
1.5 Conventions .37
1.6 General considerations .43
1.7 Conformance Test .48
2 Real-Time protocols.49
2.1 General .49
2.2 Variables – Services and Protocols .51
2.3 Messages Services and Protocols.72
2.4 Presentation and encoding of transmitted and stored data. 173
3 Multifunction Vehicle Bus .193
3.1 General . 193
3.2 Physical Layer . 195
3.3 Medium-dependent signalling. 229
3.4 Frames and telegrams . 236
3.5 Link Layer Control .242
3.6 Medium allocation. 248
3.7 Mastership transfer.260
3.8 Link Layer Interface . 265
4 Wire Train Bus (WTB) .273
4.1 General . 273
4.2 Physical layer . 275
4.3 Medium-dependent signalling. 296
4.4 Frames and telegrams . 304
4.5 Link Layer Control .308
4.6 Medium allocation. 329
4.7 Inauguration .331
4.8 Link layer interface .380
5 Train Network Management . 393
5.1 General . 393
5.2 Manager, Agents and interfaces. 394
5.3 Managed objects .397
5.4 Services and management messages . 407
5.5 Interface Procedures . 469

Annex A (informative) Tutorial on the TCN architecture . 473
Annex B (normative) Guidelines for conformance testing . 599

Bibliography . 600

61375-1 © IEC:2007(E) – 3 –
Figure 1 – Layering of the TCN.16
Figure 2 – State transition example .42
Figure 3 – Interfaces between equipment .43
Figure 4 – Interfaces between vehicles.43
Figure 5 – Train Bus and Vehicle Bus.44
Figure 6 – TCN configurations.45
Figure 7 – TCN device configuration options.46
Figure 8 – Structure of the Train Communication Network .49
Figure 9 – Real-Time Protocols layering .50
Figure 10 – LPI primitives exchange.54
Figure 11 – Check_Variable .59
Figure 12 – Individual access .63
Figure 13 – Set access.67
Figure 14 – Cluster access.70
Figure 15 – Terminal station.72
Figure 16 – Router station between WTB and MVB.73
Figure 17 – Packet format .75
Figure 18 – Link layer data transmission.77
Figure 19 – Link_Message_Data_Interface (LMI) .78
Figure 20 – Example of MVB Message_Data frame .79
Figure 21 – Example of WTB Message_Data frame.80
Figure 22 – LMI primitives .81
Figure 23 – Network layer on a Node.88
Figure 24 – Encoding of the Network_Address.91
Figure 25 – Building of the addresses in an outbound packet.93
Figure 26 – Network address encoding on the vehicle bus (example MVB).95
Figure 27 – Network address encoding on the train bus (example with WTB) .96
Figure 28 – Transport packet exchange. 102
Figure 29 – Packet formats (transport layer body). 105
Figure 30 – State transition diagram of the MTP . 114
Figure 31 – Time-out SEND_TMO . 118
Figure 32 – Time-out ALIVE_TMO. 118
Figure 33 – Transport interface . 127
Figure 34 – Multicast message with no retransmission. 134
Figure 35 – Short multicast message with no BD packets and no loss. 135
Figure 36 – Exchange with lost packets .136
Figure 37 – Packet formats . 138
Figure 38 – Protocol machine states.139
Figure 39 – Session layer transfer .150
Figure 40 – Session_Header in Call_Message (of type Am_Result). 151
Figure 41 – Application_Messages_Interface. 152
Figure 42 – Encoding of AM_ADDRESS. . 156

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Figure 43 – Reference device and structure of the document. 195
Figure 44 – MVB configuration . 196
Figure 45 – Transceiver interface .199
Figure 46 – Example of ESD segment . 201
Figure 47 – Example of terminator.202
Figure 48 – ESD backplane section (double-line). 204
Figure 49 – ESD connector arrangement . 205
Figure 50 – ESD terminator connector arrangement . 206
Figure 51 – Example of start of frame (ESD) . 207
Figure 52 – End of an ESD frame (both cases) . 208
Figure 53 – EMD medium. 209
Figure 54 – Shielding (single-line segment) . 211
Figure 55 – Single-line device attachment . 212
Figure 56 – Double-line device attachment to EMD. 213
Figure 57 – EMD connectors arrangement. 214
Figure 58 – EMD terminator strapping . 215
Figure 59 – Measurement of an EMD device. 216
Figure 60 – Attenuation measurement . 216
Figure 61 – Example of start of an EMD frame . 217
Figure 62 – EMD transmitter test circuits . 218
Figure 63 – Example of pulse waveform at EMD transmitter . 220
Figure 64 – Example of end of EMD frame . 221
Figure 65 – EMD receiver test signal . 222
Figure 66 – Optical link .224
Figure 67 – Optical connector (dimensions in millimeters). 225
Figure 68 – Example of start of OGF frame . 226
Figure 69 – Edge jitter. 227
Figure 70 – Example of active star coupler .228
Figure 71 – Example of a duplicated star coupler. 229
Figure 72 – "0" and "1" data encoding.229
Figure 73 – Non_Data symbols encoding. 230
Figure 74 – Master Start Delimiter . 230
Figure 75 – Slave Start Delimiter . 231
Figure 76 – Example of End Delimiter for EMD medium . 231
Figure 77 – Example of a valid frame (OGF medium). 232
Figure 78 – Signal skew .233
Figure 79 – Example of repeater for single-line attachment. 235
Figure 80 – Example of repeater connecting a double-line to a single line segment. 236
Figure 81 – Master Frame Format . 236
Figure 82 – Slave Frames . 237
Figure 83 – Telegram timing. 238
Figure 84 – Example of Reply delay. 239
Figure 85 – Frame spacing at the source side . 240

61375-1 © IEC:2007(E) – 5 –
Figure 86 – Frame spacing at the destination(s) . 240
Figure 87 – Frame spacing at the master side . 241
Figure 88 – Master Frame contents . 243
Figure 89 – Word ordering in a Slave Frame. 245
Figure 90 – Process Data telegram .245
Figure 91 – Message Data telegram .247
Figure 92 – Supervisory Data telegram.248
Figure 93 – Basic Periods . 249
Figure 94 – Example of construction of the Macro_Cycle . 251
Figure 95 – General_Event_Request frame format . 255
Figure 96 – Group_Event_Request frame (M = 6, C = ABCDEF) . 256
Figure 97 – Single_Event_Request frame. 256
Figure 98 – Event_Identifier_Response frame . 257
Figure 99 – Device_Status_Request.257
Figure 100 – Device_Status_Response . 258
Figure 101 – Device_Status of Class 1 device . 258
Figure 102 – Device_Status of Class 2/3/4/5 device. 258
Figure 103 – Device_Status of a device with Bus Administrator capability . 259
Figure 104 – Device_Status of a device with Gateway capability . 259
Figure 105 – Mastership Transfer states. 263
Figure 106 – Device_Status_Request (sent by current master) . 264
Figure 107 – Device_Status_Response (sent by proposed master) . 264
Figure 108 – Mastership_Transfer_Request (sent by current master). 265
Figure 109 – Mastership_Transfer_Response (sent by proposed next master) . 265
Figure 110 – Link Layer Layering. 266
Figure 111 – Wire Train Bus. 273
Figure 112 – Reference model of the WTB . 275
Figure 113 – Train Composition (two Intermediate Nodes shown) . 276
Figure 114 – Vehicle measurement . 277
Figure 115 – Connected nodes in regular operation . 278
Figure 116 – Double-line attachment . 278
Figure 117 – Grounded shield concept . 281
Figure 118 – Floating shield concept . 282
Figure 119 – Terminator. 282
Figure 120 – Direct node attachment (optional double-line). 283
Figure 121 – Indirect attachment . 284
Figure 122 – WTB connector, front view . 285
Figure 123 – Example of MAU Structure. 286
Figure 124 – Node with redundant Line Units.288
Figure 125 – Attenuation measurement . 289
Figure 126 – Shield grounding in the Line Unit. 290
Figure 127 – Fritting source and load . 290
Figure 128 – Transmitter test circuits . 292

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Figure 129 – Pulse wave form at transmitter. 293
Figure 130 – Signal and idling at transmitter . 294
Figure 131 – Receiver signal envelope . 295
Figure 132 – Receiver edge distortion . 296
Figure 133 – Idealised frame on the line (16 bit Preamble shown). 297
Figure 134 – Bit encoding.297
Figure 135 – Preamble.298
Figure 136 – End Delimiter. 298
Figure 137 – Valid frame, RxS, CS and SQE signals. 299
Figure 138 – Garbled frame, RxS, CS, SQE signals. 300
Figure 139 – Redundant Lines (as seen at a receiver) . 300
Figure 140 – Line_Disturbance signals . 301
Figure 141 – HDLC Frame structure . 304
Figure 142 – Telegram timing. 305
Figure 143 – Example of Interframe spacing. 306
Figure 144 – Frame spacing measured at the master side . 307
Figure 145 – Frame spacing at the slave . 307
Figure 146 – HDLC Data format . 308
Figure 147 – Format of HDLC Data . 309
Figure 148 – Process Data telegram. 313
Figure 149 – Format of Process Data Request . 314
Figure 150 – Format of Process Data Response. 315
Figure 151 – Message Data telegram .315
Figure 152 – Format of Message Data Request . 315
Figure 153 – Format of Message Data Response . 316
Figure 154 – Supervisory telegram .316
Figure 155 – Detection telegram. 317
Figure 156 – Format of Detect Request . 318
Figure 157 – Format of Detect Response . 318
Figure 158 – Presence telegram. 319
Figure 159 – Format of Presence Request. 319
Figure 160 – Format of Presence Response . 320
Figure 161 – Status telegram .320
Figure 162 – Format of Status Request . 321
Figure 163 – Format of Status Response. 322
Figure 164 – Set-to-Intermediate telegram. 322
Figure 165 – Format of SetInt Request . 322
Figure 166 – Format of SetInt Response . 323
Figure 167 – Naming telegram . 323
Figure 168 – Format of Naming Request . 324
Figure 169 – Format of Naming Response. 324
Figure 170 – Unnaming telegram. 325
Figure 171 – Format of Unname Request . 325

61375-1 © IEC:2007(E) – 7 –
Figure 172 – Set to End telegram . 325
Figure 173 – Format of SetEnd Request. 326
Figure 174 – Format of SetEnd Response . 326
Figure 175 – Topography telegram . 327
Figure 176 – Format of Topography Request. 327
Figure 177 – Format of Topography Response . 328
Figure 178 – Structure of the Basic Period. 329
Figure 179 – Node position numbering . 332
Figure 180 – Format of Node Descriptor . 333
Figure 181 – Format of Node Report . 334
Figure 182 – Format of User Report . 334
Figure 183 – Format of Composition Strength. 335
Figure 184 – Master_Report. 336
Figure 185 – Format of Topo Counter. 336
Figure 186 – Format of Master Topo . 336
Figure 187 – Timing Diagram of detection protocol . 339
Figure 188 – Major node states and application settings . 340
Figure 189 – Node processes (End Setting). 341
Figure 190 – AUXILIARY_PROCESS states . 347
Figure 191 – NAMING_RESPONSE macro . 348
Figure 192 – States of MAIN PROCESS . 349
Figure 193 – Macro ‘START_NODE’.352
Figure 194 – Procedure REQUEST_RESPONSE . 354
Figure 195 – Procedures ‘SET_TO_INT’ and ‘SET_TO_END’ . 355
Figure 196 – Macro ‘INIT_MASTER’ . 356
Figure 197 – Macro ‘NAMING_MASTER’ . 357
Figure 198 – Macro ASK_END . 358
Figure 199 – Procedure NAME_ONE .361
Figure 200 – Macro TEACHING_MASTER. 363
Figure 201 – Macro ‘UNNAMING_MASTER’ . 364
Figure 202 – Macro ‘REGULAR_MASTER’ . 366
Figure 203 – Macro CHECK_DESC . 367
Figure 204 – Macro PERIODIC_POLL . 369
Figure 205 – Macro MESSAGE_POLL . 370
Figure 206 – States ‘UNNAMED_SLAVE’. 372
Figure 207 – States ‘NAMED_SLAVE’ . 374
Figure 208 – Macro ‘LEARNING_SLAVE’.376
Figure 209 – Macro ‘REGULAR_SLAVE’. 378
Figure 210 – Link layer layering.380
Figure 211 – Management messages . 395
Figure 212 – Agent Interface on a (gateway) Station. 396
Figure 213 – Station_Status .398
Figure A.1 – Train_Bus and Vehicle_Busses . 475

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Figure A.2 – Data transfer over the Train Communication Network . 477
Figure A.3 – Example of Periodic_Data and Sporadic_Data transmission. 478
Figure A.4 – TCN Services . 479
Figure A.5 – Application Tasks and TCN services. 480
Figure A.6 – Layering of the Real-Time Protocols . 480
Figure A.7 – Variable transmission and Ports . 482
Figure A.8 – Broadcasting of source-addressed Process_Data . 483
Figure A.9 – Port and Traffic_Store . 484
Figure A.10 – Ports on the Wire_Train_Bus . 486
Figure A.11 – Dataset .487
Figure A.12 – Validity bits.488
Figure A.13 – Multiple Process_Variable instances . 489
Figure A.14 – Instances of a Process_Variable. 490
Figure A.15 – Transmission of Periodic_Data through the network . 491
Figure A.16 – Individual copying . 494
Figure A.17 – Cluster transfer . 495
Figure A.18 – Application_Layer and Link_Layer Interface to Process_Variables. 496
Figure A.19 – Several Applications access the same Traffic_Store . 496
Figure A.20 – Application access to several Traffic_Stores . 497
Figure A.21 – Two-level hierarchy . 498
Figure A.22 – Call_Message/Reply_Message exchange. 500
Figure A.23 – Example of actual architecture. 501
Figure A.24 – Message_Data transmission over queues . 502
Figure A.25 – Link_Layer in the OSI hierarchy . 503
Figure A.26 – Message_Data format . 504
Figure A.27 – Node position numbering . 504
Figure A.28 – Vehicle numbering according to UIC 556 – not TCN . 505
Figure A.29 – Example of vehicle types . 506
Figure A.30 – Nodes and Vehicle_Bus Devices.507
Figure A.31 – Vehicle_Bus spanning several vehicles. 507
Figure A.32 – System view of communication . 508
Figure A.33 – Station_Directory. 509
Figure A.34 – Actual Station location . 510
Figure A.35 – Dual-processor Node. 511
Figure A.36 – Further hierarchical level . 512
Figure A.37 – Functions within a passenger coach. 512
Figure A.38 – Mapping of Functions to Devices . 513
Figure A.39 – Function view of communication . 514
Figure A.40 – Function_Directory . 514
Figure A.41 – Function Directories in a three-level hierarchy. 515
Figure A.42 – End-to-end Message_Data transfer. 516
Figure A.43 – Packet forwarding over the network . 517
Figure A.44 – Network_Address (origin or final) for messages . 517

61375-1 © IEC:2007(E) – 9 –
Figure A.45 – WTB and MVB Message_Data frame with Network_Addresses . 518
Figure A.46 – Routing messages over the Train_Bus. 520
Figure A.47 – Execution of the transport control. . 521
Figure A.48 – Message Transport_Layer in the OSI model. 522
Figure A.49 – Sliding window protocol . 523
Figure A.50 – Frame exchange at the transport level . 524
Figure A.51 – Packet formats (bus-independent) . 526
Figure A.52 – Multicast transmission . 527
Figure A.53 – Remote Procedure Call. 529
Figure A.54 – Call nesting . 530
Figure A.55 – Example of message exchange at the session level . 531
Figure A.56 – Message Software structure .532
Figure A.57 – Multifunction_Vehicle_Bus in a locomotive . 537
Figure A.58 – Multifunction_Vehicle_Bus in a coach . 537
Figure A.59 – Electrical Short Distance medium . 539
Figure A.60 – MVB spanning three vehicles. 540
Figure A.61 – Vehicle_Bus optical star configuration. 540
Figure A.62 – Topology of the Vehicle Bus .541
Figure A.63 – Bus_Controller .542
Figure A.64 – Bus interface for class 1 device . 543
Figure A.65 – Bus Interface for Class 2/3 devices. 544
Figure A.66 – Frame delimiter, Manchester-encoded data and Check_Sequence . 545
Figure A.67 – Telegram. 545
Figure A.68 – Master_Frame and Slave_Frame formats . 546
Figure A.69 – MVB Process_Data Telegram . 548
Figure A.70 – MVB Message_Data Telegram. 548
Figure A.71 – MVB Supervisory_Data Telegram . 549
Figure A.72 – Ports in the Traffic_Store. 550
Figure A.73 – MVB Traffic .551
Figure A.74 – Periodic traffic configuration . 551
Figure A.75 – Single response to a General_Event_Request (Start) frame . 553
Figure A.76 – Event_Round with single response (no arbitration) . 553
Figure A.77 – First Event_Arbitration . 554
Figure A.78 – Group_Event_Request. 555
Figure A.79 – Event_Arbitration tree. 555
Figure A.80 – Fully redundant bus .558
Figure A.81 – MVB redundant optical layout . 558
Figure A.82 – Mastership transfer with multiple masters . 559
Figure A.83 – Wire_Train_Bus . 560
Figure A.84 – WTB topology. 561
Figure A.85 – WTB cable arrangement (top view) . 562
Figure A.86 – Medium_Attachment_Unit (switches shown for an End_Node). 563
Figure A.87 – WTB MAU with duplicated Line_Unit. 564

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Figure A.88 – WTB signal encoding. 564
Figure A.89 – WTB Frame (extended ISO/IEC 13239) . 565
Figure A.90 – WTB Telegram . 566
Figure A.91 – WTB Process_Data Telegram.
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