IEC 61158-4-2:2023

IEC 61158-4-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Fieldbus specifications –
Part 4-2: Data-link layer protocol specification – Type 2 elements
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IEC 61158-4-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Fieldbus specifications –

Part 4-2: Data-link layer protocol specification – Type 2 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-6554-3

– 2 – IEC 61158-4-2:2023 © IEC 2023
CONTENTS
FOREWORD . 16
INTRODUCTION . 18
1 Scope . 19
1.1 General . 19
1.2 Specifications . 19
1.3 Procedures . 19
1.4 Applicability . 20
1.5 Conformance . 20
2 Normative references . 20
3 Terms, definitions, symbols, abbreviated terms and conventions . 22
3.1 Reference model terms and definitions . 22
3.2 Service convention terms and definitions . 24
3.3 Common terms and definitions . 24
3.4 Additional Type 2 definitions . 25
3.5 Type 2 symbols and abbreviated terms . 33
3.6 Conventions for station management objects . 34
4 Overview of the data-link protocol . 35
4.1 General . 35
4.1.1 DLL architecture . 35
4.1.2 Access control machine (ACM) and scheduling support functions . 37
4.1.3 Connection-mode, connectionless-mode data transfer and DL service . 37
4.2 Services provided by the DL . 37
4.2.1 Overview . 37
4.2.2 QoS . 38
4.3 Structure and definition of DL-addresses . 38
4.3.1 General . 38
4.3.2 MAC ID address . 39
4.3.3 Generic tag address . 40
4.3.4 Fixed tag address . 40
4.4 Services assumed from the PhL . 41
4.4.1 General requirements . 41
4.4.2 Data encoding rules . 41
4.4.3 DLL to PhL interface . 42
4.5 Functional classes . 44
5 General structure and encoding of PhIDUs and DLPDUs and related elements of
procedure . 44
5.1 Overview. 44
5.2 Media access procedure . 44
5.3 DLPDU structure and encoding . 48
5.3.1 General . 48
5.3.2 DLPDU components . 48
5.3.3 Preamble . 48
5.3.4 Start and end delimiters . 48
5.3.5 DLPDU octets and ordering . 48
5.3.6 Source MAC ID . 49
5.3.7 Lpackets field . 49
5.3.8 Frame check sequence (FCS) . 49

5.3.9 Null DLPDU . 52
5.3.10 Abort DLPDU . 52
5.4 Lpacket components . 52
5.4.1 General Lpacket structure. 52
5.4.2 Size . 53
5.4.3 Control . 53
5.4.4 Generic tag Lpackets . 53
5.4.5 Fixed tag Lpackets . 54
5.5 DLPDU procedures . 54
5.5.1 General . 54
5.5.2 Sending scheduled DLPDUs . 55
5.5.3 Sending unscheduled DLPDUs . 55
5.5.4 Receiving DLPDUs . 55
5.6 Summary of DLL support services and objects . 56
6 Specific DLPDU structure, encoding and procedures . 57
6.1 Modeling language . 57
6.1.1 State machine description. 57
6.1.2 Use of DLL- prefix . 58
6.1.3 Data types . 58
6.2 DLS user services . 59
6.2.1 General . 59
6.2.2 Connected mode and connectionless mode transfer service . 60
6.2.3 Queue maintenance service . 61
6.2.4 Tag filter service . 61
6.2.5 Link synchronization service . 62
6.2.6 Synchronized parameter change service. 62
6.2.7 Event reports service . 63
6.2.8 Bad FCS service . 64
6.2.9 Current moderator service . 64
6.2.10 Power up and online services . 64
6.2.11 Enable moderator service . 65
6.2.12 Listen only service . 65
6.3 Generic tag Lpacket . 65
6.3.1 General . 65
6.3.2 Structure of the generic-tag Lpacket . 65
6.3.3 Sending and receiving the generic-tag Lpacket . 66
6.4 Moderator Lpacket . 66
6.4.1 General . 66
6.4.2 Structure of the moderator Lpacket . 66
6.4.3 Sending and receiving the moderator Lpacket . 66
6.5 Time distribution Lpacket . 67
6.5.1 General . 67
6.5.2 Structure of the time distribution Lpacket . 67
6.5.3 Sending and receiving the time distribution Lpacket . 69
6.6 UCMM Lpacket . 70
6.6.1 General . 70
6.6.2 Structure of the UCMM Lpacket . 70
6.6.3 Sending and receiving the UCMM Lpacket . 70
6.7 Keeper UCMM Lpacket . 70

– 4 – IEC 61158-4-2:2023 © IEC 2023
6.7.1 General . 70
6.7.2 Structure of the Keeper UCMM Lpacket . 70
6.7.3 Sending and receiving the Keeper UCMM Lpacket . 70
6.8 TUI Lpacket . 71
6.8.1 General . 71
6.8.2 Structure of the TUI Lpacket . 71
6.8.3 Sending and receiving the TUI Lpacket . 72
6.9 Link parameters Lpacket and tMinus Lpacket . 72
6.9.1 General . 72
6.9.2 Structure of link parameters and tMinus Lpackets . 72
6.9.3 Sending and receiving the tMinus and Link parameters Lpackets . 73
6.10 I'm-alive Lpacket . 73
6.10.1 General . 73
6.10.2 Structure or the I'm-alive Lpacket . 73
6.10.3 Sending and receiving I'm Alive . 74
6.10.4 I'm alive state processing . 74
6.11 Ping Lpackets . 75
6.11.1 General . 75
6.11.2 Structure of the ping Lpackets . 76
6.11.3 Sending and receiving the ping Lpackets . 76
6.12 WAMI Lpacket. 76
6.12.1 General . 76
6.12.2 Structure of the WAMI Lpacket . 77
6.12.3 Sending and receiving the WAMI Lpacket . 77
6.13 Debug Lpacket . 77
6.14 IP Lpacket . 78
6.15 Ethernet Lpacket . 78
7 Objects for station management . 78
7.1 General . 78
7.2 ControlNet™ object . 80
7.2.1 Overview . 80
7.2.2 Class attributes . 80
7.2.3 Instance attributes . 80
7.2.4 Common services . 89
7.2.5 Class specific services . 90
7.2.6 Behavior . 91
7.2.7 Module status indicator . 91
7.3 Keeper object . 92
7.3.1 Overview . 92
7.3.2 Revision history . 92
7.3.3 Class attributes . 92
7.3.4 Instance attributes . 92
7.3.5 Common services . 101
7.3.6 Class specific services . 102
7.3.7 Service error codes . 108
7.3.8 Behavior . 108
7.3.9 Miscellaneous notes . 109
7.3.10 Keeper power up sequence . 110
7.4 Scheduling object . 115

7.4.1 Overview . 115
7.4.2 Class attributes . 116
7.4.3 Instance attributes . 116
7.4.4 Common services . 117
7.4.5 Class specific services . 119
7.4.6 Typical scheduling session . 125
7.5 TCP/IP Interface object . 126
7.5.1 Overview . 126
7.5.2 Revision history . 126
7.5.3 Class attributes . 126
7.5.4 Instance attributes . 127
7.5.5 Diagnostic connection points . 142
7.5.6 Common services . 142
7.5.7 Class specific services . 145
7.5.8 Behavior . 147
7.5.9 Address Conflict Detection (ACD) . 148
7.6 Ethernet Link object . 154
7.6.1 Overview . 154
7.6.2 Revision history . 154
7.6.3 Class attributes . 154
7.6.4 Instance attributes . 155
7.6.5 Diagnostic connection points . 165
7.6.6 Common services . 166
7.6.7 Class specific services . 167
7.6.8 Behavior . 168
7.7 DeviceNet™ object . 169
7.7.1 Overview . 169
7.7.2 Revision history . 170
7.7.3 Class attributes . 170
7.7.4 Instance attributes . 170
7.7.5 Common services . 177
7.7.6 Class specific services . 178
7.8 Connection Configuration object (CCO) . 179
7.8.1 Overview . 179
7.8.2 Revision history . 179
7.8.3 Class attributes . 179
7.8.4 Instance attributes . 181
7.8.5 Connection Configuration object change control . 190
7.8.6 Common services . 190
7.8.7 Class specific services . 196
7.8.8 Behavior . 200
7.9 DLR object . 200
7.9.1 Overview . 200
7.9.2 Revision history . 201
7.9.3 Class attributes . 201
7.9.4 Instance attributes . 201
7.9.5 Diagnostic connection points . 213
7.9.6 Common services . 213
7.9.7 Class specific services . 217

– 6 – IEC 61158-4-2:2023 © IEC 2023
7.10 QoS object . 218
7.10.1 Overview . 218
7.10.2 Revision History . 218
7.10.3 Class attributes . 218
7.10.4 Instance Attributes . 219
7.10.5 Common services . 220
7.11 Port object . 221
7.11.1 Overview . 221
7.11.2 Revision History . 221
7.11.3 Class attributes . 222
7.11.4 Instance attributes . 222
7.11.5 Common services . 229
7.12 PRP/HSR Protocol object . 231
7.12.1 Overview . 231
7.12.2 Revision history . 231
7.12.3 Class attributes . 231
7.12.4 Instance attributes . 231
7.12.5 Diagnostic connection points . 239
7.12.6 Common Services. 239
7.13 PRP/HSR Nodes Table object . 241
7.13.1 Overview . 241
7.13.2 Revision history . 241
7.13.3 Class attributes . 242
7.13.4 Instance attributes . 242
7.13.5 Common services . 244
7.14 LLDP Management object . 245
7.14.1 Overview . 245
7.14.2 Revision history . 245
7.14.3 Class attributes . 246
7.14.4 Instance attributes . 246
7.14.5 Common services . 247
7.15 LLDP Data Table object . 248
7.15.1 Overview . 248
7.15.2 Revision history . 249
7.15.3 Class attributes . 249
7.15.4 Instance attributes . 249
7.15.5 Common services . 253
8 Other DLE elements of procedure . 254
8.1 Network attachment monitor (NAM) . 254
8.1.1 General . 254
8.1.2 Default parameters . 256
8.1.3 Auto-addressing . 256
8.1.4 Valid MAC IDs . 257
8.1.5 State machine description. 257
8.2 Calculating link parameters . 263
8.2.1 Link parameters . 263
8.2.2 Conditions affecting link parameters . 263
8.2.3 Moderator change . 263
8.2.4 NUT timing . 264

8.2.5 Slot timing . 265
8.2.6 Blanking . 266
8.2.7 Example implementation . 266
9 Detailed specification of DL components . 271
9.1 General . 271
9.2 Access control machine (ACM) . 271
9.3 TxLLC . 290
9.4 RxLLC . 295
9.5 Transmit machine (TxM) . 298
9.6 Receive machine (RxM) . 302
9.7 Serializer . 308
9.8 Deserializer . 310
9.8.1 Octet construction . 310
9.8.2 FCS checking . 311
9.8.3 End of DLPDU processing . 311
9.9 DLL management . 311
10 Device Level Ring (DLR) protocol . 313
10.1 General . 313
10.2 Support for Multiple DLR Ring Pairs . 314
10.3 Supported topologies . 315
10.4 Overview of DLR operation . 316
10.4.1 Normal operation . 316
10.4.2 Link failures . 317
10.5 Classes of DLR implementation . 318
10.6 DLR behavior . 319
10.6.1 DLR variables . 319
10.6.2 Ring supervisor . 319
10.6.3 Ring node . 322
10.6.4 Sign on process . 323
10.6.5 Neighbor check process . 324
10.7 Implementation requirements . 324
10.7.1 Embedded switch requirements and recommendations . 324
10.7.2 DLR implementation requirements . 325
10.7.3 IEC 61588 and Type 2 Ethernet considerations . 326
10.7.4 IEEE Std 802.1Q-2018 STP/RSTP/MSTP considerations . 326
10.8 Using non-DLR nodes in the ring network . 326
10.8.1 General considerations . 326
10.8.2 Non-DLR end devices . 327
10.8.3 Non-DLR switches . 327
10.9 Redundant gateway devices on DLR network . 329
10.9.1 General . 329
10.9.2 Supported topologies . 330
10.9.3 Redundant gateway capable device . 330
10.9.4 Redundant gateway device behavior. 331
10.10 DLR messages . 334
10.10.1 General . 334
10.10.2 Common frame header . 335
10.10.3 Beacon frame . 336
10.10.4 Neighbor_Check request . 336

– 8 – IEC 61158-4-2:2023 © IEC 2023
10.10.5 Neighbor_Check_response . 337
10.10.6 Link_Status/Neighbor_Status . 337
10.10.7 Locate_Fault . 338
10.10.8 Announce . 338
10.10.9 Sign_On . 338
10.10.10 Advertise . 339
10.10.11 Flush_Tables . 339
10.10.12 Learning_Update . 340
10.11 State diagrams and state-event-action matrices . 340
10.11.1 Beacon-based ring node . 340
10.11.2 Announce-based ring node . 347
10.11.3 Ring supervisor . 351
10.11.4 Redundant gateway . 366
10.12 Performance analysis. 369
10.12.1 General . 369
10.12.2 Redundant gateway switchover performance . 373
11 PRP and HSR redundancy protocols . 375
11.1 General . 375
11.2 PRP overview . 375
11.2.1 General . 375
11.2.2 Address Conflict Detection (ACD) . 376
11.3 HSR overview . 377
12 LLDP protocol . 378
12.1 General . 378
12.2 LLDP overview . 379
12.3 Type 2 LLDP Transmission Requirements . 379
12.3.1 General . 379
12.3.2 Chassis ID TLV (TLV Type = 1) . 380
12.3.3 Port ID TLV (TLV Type = 2) . 380
12.3.4 System Capabilities TLV (TLV Type = 7) . 381
12.3.5 Management Address (TLV Type = 8) . 381
12.3.6 Type 2 Identification TLV (TLV Type = 127) . 381
12.3.7 Type 2 MAC Address TLV (TLV Type = 127) . 381
12.3.8 Type 2 Interface Label TLV (TLV Type = 127) . 381
12.3.9 Additional Ethernet Capabilities TLV (TLV Type = 127) . 382
12.4 Type 2 LLDP Reception Requirements . 382
12.5 Type 2 LLDP Reporting Requirements . 382
12.6 EtherNet/IP LLDP Link State Transition Requirements . 382
Annex A (normative) Indicators and switches . 383
A.1 Purpose . 383
A.2 Indicators . 383
A.2.1 General indicator requirements . 383
A.2.2 Common indicator requirements . 383
A.2.3 Fieldbus specific indicator requirements – option 1 . 385
A.2.4 Fieldbus specific indicator requirements – option 2 . 389
A.2.5 Fieldbus specific indicator requirements – option 3 . 393
A.3 Switches . 398
A.3.1 Common switch requirements . 398
A.3.2 Fieldbus specific switch requirements – option 1 . 398

A.3.3 Fieldbus specific switch requirements – option 2 . 398
A.3.4 Fieldbus specific switch requirements – option 3 . 399
Bibliography . 400

Figure 1 – Data-link layer internal architecture . 36
Figure 2 – Relationships of DLSAPs, DLSAP-addresses, and group DL-addresses . 39
Figure 3 – Basic structure of a MAC ID address . 39
Figure 4 – Basic structure of a generic tag address .
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