IEC TR 61850-90-4:2013

Communication networks and systems for power utility automation - Part 90-4: Network engineering guidelines

IEC/TR 61850-90-4:2013(E) is intended for an audience familiar with network communication and/or IEC 61850-based systems and particularly for substation protection and control equipment vendors, network equipment vendors and system integrators. This Technical Report focuses on engineering a local area network limited to the requirements of IEC 61850-based substation automation. It outlines the advantages and disadvantages of different approaches to network topology, redundancy, clock synchronization, etc. so that the network designer can make educated decisions. In addition, this report outlines possible improvements to both substation automation and networking equipment. This Technical Report addresses the most critical aspects of IEC 61850, such as protection related to tripping over the network. This Technical Report addresses in particular the multicast data transfer of large volumes of sampled values from merging units. It also considers the high precision clock synchronization and "seamless" guaranteed transport of data across the network under failure conditions that is central to the process bus concept.

General Information

• Status: Published
• Publication Date: 05-Aug-2013
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.200 - Telecontrol. Telemetering
• Technical Committee: TC 57 - Power systems management and associated information exchange
• Drafting Committee: WG 10 - TC 57/WG 10
• Current Stage: DELPUB - Deleted Publication
• Start Date: 25-May-2020
• Completion Date: 26-Oct-2025

Standards Content (Sample)

IEC/TR 61850-90-4 ®
Edition 1.0 2013-08
TECHNICAL
REPORT
colour
inside
Communication networks and systems for power utility automation –
Part 90-4: Network engineering guidelines

IEC/TR 61850-90-4:2013(E)
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.
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Edition 1.0 2013-08
TECHNICAL
REPORT
colour
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Communication networks and systems for power utility automation –

Part 90-4: Network engineering guidelines

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
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ICS 33.200 ISBN 978-2-8322-0903-5

– 2 – TR 61850-90-4 © IEC:2013(E)
CONTENTS
FOREWORD . 12
INTRODUCTION . 14
1 Scope . 15
2 Normative references . 16
3 Terms, definitions, abbreviations and conventions . 19
3.1 Terms and definitions . 19
3.2 Abbreviations . 22
3.3 Conventions . 25
3.3.1 Network diagram symbols . 25
3.3.2 Port and link symbols . 26
3.3.3 Bridges symbols . 26
4 Overview of IEC 61850 networks . 27
4.1 Logical allocation of functions and interfaces . 27
4.2 IEC 61850 protocol stack . 29
4.2.1 General . 29
4.2.2 IEC 61850 traffic classes . 29
4.2.3 MMS protocol . 30
4.2.4 GOOSE protocol . 30
4.2.5 SV protocol . 32
4.3 Station bus and process bus . 32
5 Network design checklist . 34
5.1 Design principles . 34
5.2 Engineering flow . 34
5.3 Checklist to be observed . 35
5.3.1 Summary . 35
5.3.2 Environmental issues . 36
5.3.3 EMI immunity . 36
5.3.4 Form factor . 36
5.3.5 Physical media . 36
5.3.6 Substation application and network topology . 36
5.3.7 Redundancy . 37
5.3.8 Reliability, availability, maintainability . 37
5.3.9 Logical data flows and traffic patterns . 37
5.3.10 Latency for different types of traffic . 37
5.3.11 Performance . 37
5.3.12 Network management . 38
5.3.13 Network supervision . 38
5.3.14 Time synchronization and accuracy . 38
5.3.15 Remote connectivity . 38
5.3.16 Cyber security . 38
5.3.17 Scalability, upgradeability and future-proof . 39
5.3.18 Testing . 39
5.3.19 Cost . 39
6 Ethernet technology for substations . 39
6.1 Ethernet subset for substation automation . 39
6.2 Topology . 39

TR 61850-90-4 © IEC:2013(E) – 3 –
6.3 Physical layer . 41
6.3.1 Data rate and medium . 41
6.3.2 Full-duplex communication and auto-negotiation . 41
6.3.3 Copper cabling at 100 Mbit/s . 41
6.3.4 Optical cabling at 100 Mbit/s (100BASE-FX) . 42
6.3.5 Optical cabling at 1 Gbit/s (1000BASE-LX) . 44
6.3.6 Copper cabling at 1 Gbit/s . 44
6.4 Link layer . 44
6.4.1 Unicast and multicast MAC addresses . 44
6.4.2 Link layer and bridges . 45
6.4.3 Bridging nodes . 45
6.4.4 Loop prevention and RSTP . 45
6.4.5 Traffic control in the bridges . 47
6.4.6 Unicast MAC address filtering . 47
6.4.7 Multicast MAC address filtering . 47
6.4.8 Virtual LANs (VLANS) traffic control . 48
6.4.9 Comparison VLAN versus multicast filtering. 53
6.4.10 Layer 2 redundancy protocols . 53
6.5 Network layer . 57
6.5.1 Internet protocol . 57
6.5.2 IP public and private addresses . 57
6.5.3 Subnet masks . 58
6.5.4 Network address translation . 59
7 Network and substation topologies . 59
7.1 General rule . 59
7.2 Reference topologies and network redundancy. 60
7.3 Reference topologies . 64
7.3.1 Station bus topologies . 64
7.3.2 Process bus and attachment of primary equipment . 77
7.3.3 Station bus and process bus connection . 92
8 Addressing in the substation . 98
8.1 Network IP address plan for substations . 98
8.1.1 General structure . 98
8.1.2 IP address allocation of NET . 99
8.1.3 IP address allocation of BAY . 100
8.1.4 IP address allocation of device . 100
8.1.5 IP address allocation of devices with PRP . 101
8.2 Routers and GOOSE / SV traffic . 101
8.3 Communication outside the substation . 101
9 Application parameters . 102
9.1 MMS parameters . 102
9.2 GOOSE parameters . 102
9.3 SV parameters . 102
10 Performance . 103
10.1 Station bus performance . 103
10.1.1 Logical data flows and traffic patterns . 103
10.1.2 GOOSE traffic estimation . 104
10.1.3 MMS traffic estimation . 104

– 4 – TR 61850-90-4 © IEC:2013(E)
10.1.4 station bus measurements . 105
10.2 Process bus performance . 106
11 Latency . 106
11.1 Application requirements . 106
11.2 Latency requirements for different types of traffic . 107
11.2.1 Latency requirements in IEC 61850-5 . 107
11.2.2 Latencies of physical paths . 107
11.2.3 Latencies of bridges . 107
11.2.4 Latency and hop counts . 108
11.2.5 Network latency budget . 108
11.2.6 Example of traffic delays . 109
11.2.7 Engineering a network for IEC 61850 protection . 109
12 Network traffic control . 110
12.1 Factors that affect performance . 110
12.1.1 Influencing factors . 110
12.1.2 Traffic reduction . 110
12.1.3 Example of traffic reduction scheme . 111
12.1.4 Multicast domains in a combined station bus and process bus
network . 112
12.2 Traffic control by VLANs . 113
12.2.1 Trunk traffic reduction by VLANs . 113
12.2.2 VLAN usage . 114
12.2.3 VLAN handling at the IEDs . 114
12.2.4 Example of correct VLAN configuration . 114
12.2.5 Example of incorrect VLAN configuration . 115
12.2.6 Retaining priority throughout the network. 117
12.2.7 Traffic filtering with VLANs . 117
12.3 Traffic control by multicast filtering . 118
12.3.1 Trunk traffic reduction by multicast filtering . 118
12.3.2 Multicast/VLAN management and redundancy protocol
reconfiguration . 119
12.3.3 Physical topologies and multicast management implications . 119
12.4 Configuration support from tools and SCD files . 122
13 Dependability . 122
13.1 Resiliency requirements . 122
13.2 Availability and reliability requirements . 123
13.3 Recovery time requirements . 123
13.4 Maintainability requirements . 123
13.5 Dependability calculations . 124
13.6 Risk analysis attached to "unwanted events" . 124
14 Time services . 125
14.1 Clock synchronization and accuracy requirements . 125
14.2 Global time sources . 125
14.3 Time scales and leap seconds . 126
14.4 Epoch . 127
14.5 Time scales in IEC 61850 . 127
14.6 Synchronization mechanisms in IEC 61850 . 128
14.6.1 Clock synchronization protocols . 128
14.6.2 1 PPS . 130

TR 61850-90-4 © IEC:2013(E) – 5 –
14.6.3 IRIG-B . 130
14.6.4 NTP/SNTP clock synchronization for IEC 61850-8-1 (station bus) . 130
14.6.5 PTP (IEC 61588) synchronization . 132
14.6.6 PTP clock synchronization and IEC 62439-3:2012 . 137
14.6.7 IEEE C37.238-2011 Power profile . 140
14.7 PTP network engineering . 141
14.7.1 PTP reference clock location . 141
14.7.2 PTP connection of station bus and process bus . 142
14.7.3 Merging units synchronization . 143
15 Network security . 143
16 Network management . 143
16.1 Protocols for network management. 143
16.2 Network management tool . 144
16.3 Network diagnostic tool . 144
17 Remote connectivity . 145
18 Network testing . 145
18.1 Introduction to testing . 145
18.2 Environmental type testing . 146
18.3 Conformance testing . 146
18.3.1 Protocols subject to conformance testing . 146
18.3.2 Integrator acceptance and verification testing . 147
18.3.3 Simple verification test set-up . 147
18.3.4 Simple VLAN handling test . 148
18.3.5 Simple priority tagging test . 148
18.3.6 Simple multicast handling test . 149
18.3.7 Simple RSTP recovery test . 149
18.3.8 Simple HSR test . 150
18.3.9 Simple PRP test . 150
18.3.10 Simple PTP test . 150
18.4 Factory and site acceptance testing . 150
19 IEC 61850 bridge and port object model . 151
19.1 Purpose . 151
19.2 Bridge model . 152
19.2.1 Simple model . 152
19.2.2 Bridge Logical Node linking . 154
19.3 Clock model . 154
19.3.1 IEC 61588 datasets . 154
19.3.2 Clock objects . 155
19.3.3 Simple clock model . 155
19.3.4 Linking of clock objects . 156
19.4 Autogenerated IEC 61850 objects . 157
19.4.1 General . 157
19.4.2 Abbreviated terms used in data object names . 157
19.4.3 Logical nodes . 158
19.4.4 Data semantics . 171
19.4.5 Enumerated data attribute types . 174
19.4.6 SCL enumerations . 176
19.4.7 Common data class specifications . 176

– 6 – TR 61850-90-4 © IEC:2013(E)
19.4.8 Enumerated types . 182
19.4.9 SCL enumerations . 183
19.5 Mapping of bridge objects to SNMP . 183
19.5.1 Mapping of LLN0 and LPHD attributes to SNMP . 183
19.5.2 Mapping of LBRI attributes to SNMP for bridges . 184
19.5.3 Mapping of LPCP attributes to SNMP for bridges . 184
19.5.4 Mapping of LPLD attributes to SNMP for bridges . 184
19.5.5 Mapping of HSR/PRP link redundancy entity to SNMP . 185
19.6 Mapping of clock objects to the C37.238 SNMP MIB . 186
19.7 Machine-readable description of the bridge objects . 189
19.7.1 Method and examples . 189
19.7.2 Four-port bridge . 189
19.7.3 Simple IED with PTP . 199
19.7.4 RedBox wit HSR . 206
Annex A (informative) Case study – Process bus configuration for busbar protection
system . 214
Annex B (informative) Case study – Simple Topologies (Transener/Transba,
Argentina) . 218
Annex C (informative) Case study – An IEC 61850 station bus (Powerlink, Australia) . 226
Annex D (informative) Case study – Station bus with VLANs (Trans-Africa, South
Africa) . 242
Bibliography . 263

Figure 1 – Network symbols . 26
Figure 2 – Port symbols . 26
Figure 3 – Bridge symbol as beam . 27
Figure 4 – Bridge symbol as bus . 27
Figure 5 – Levels and logical interfaces in substation automation systems . 28
Figure 6 – IEC 61850 protocol stack . 29
Figure 7 – MMS protocol time/distance chart . 30
Figure 8 – GOOSE protocol time/distance chart . 31
Figure 9 – GOOSE protocol time chart . 32
Figure 10 – Example of SV traffic (4 800 Hz) . 32
Figure 11 – Station bus, process bus and traffic example . 33
Figure 12 – Example of engineering flow . 35
Figure 13 – Ethernet local area network (with redundant links) . 40
Figure 14 – Switch with copper (RJ45) ports) . 40
Figure 15 – RJ45 connector . 42
Figure 16 – LC connector . 43
Figure 17 – Switch with optical fibres (LC connectors) . 44
Figure 18 – RSTP principle . 46
Figure 19 – IEEE 802.3 frame format without and with VLAN tagging. 49
Figure 20 – PRP principle . 54
Figure 21 – HSR principle . 56
Figure 22 – HSR and PRP coupling (multicast) . 57
Figure 23 – Mapping of electrical grid to data network topology . 60

TR 61850-90-4 © IEC:2013(E) – 7 –
Figure 24 – Station bus as single bridge . 64
Figure 25 – Station bus as hierarchical star . 65
Figure 26 – Station bus as dual star with PRP . 66
Figure 27 – Station bus as ring of RSTP bridges . 67
Figure 28 – Station bus as separated Main 1 (Bus 1) and Main 2 (Bus 2) LANs . 68
Figure 29 – Station bus as ring of HSR bridging nodes . 70
Figure 30 – Station bus as ring and subrings with RSTP . 71
Figure 31 – Station bus as parallel rings with bridging nodes . 72
Figure 32 – Station bus as parallel HSR rings . 73
Figure 33 – Station bus as hierarchical rings with RSTP bridging nodes . 74
Figure 34 – Station bus as hierarchical rings with HSR bridging nodes . 76
Figure 35 – Station bus as ring and subrings with HSR . 77
Figure 36 – Double busbar bay with directly attached sensors . 78
Figure 37 – Double busbar bay with SAMUs and process bus . 79
Figure 38 – Double busbar bay with ECT/EVTs and process bus . 80
Figure 39 – 1 ½ CB diameter with conventional, non-redundant attachment . 81
Figure 40 – 1 ½ CB diameter with SAMUs and process bus . 82
Figure 41 – 1 ½ CB diameter with ECT/EVT and process bus . 83
Figure 42 – Process bus as connection of PIA and PIB (non-redundant protection). 84
Figure 43 – Process bus as single star (not redundant protection) . 85
Figure 44 – Process bus as dual star . 87
Figure 45 – Process bus as a single bridge (no protection redundancy) . 88
Figure 46 – Process bus as separated LANs for main 1 and main 2 . 90
Figure 47 – Process bus as ring of HSR nodes . 91
Figure 48 – Process bus as star to merging units and station bus as RSTP ring . 93
Figure 49 – Station bus and process bus as rings connected by a router . 95
Figure 50 – Station bus ring and process bus ring with HSR . 96
Figure 51 – Station bus as dual PRP ring and process bus as HSR ring . 98
Figure 52 – Station bus used for the measurements . 105
Figure 53 – Typical traffic (packet/s) on the station bus . 105
Figure 54 – Generic multicast domains . 110
Figure 55 – Traffic patterns . 112
Figure 56 – Multicast domains for a combined process bus and station bus . 113
Figure 57 – Bridges with correct VLAN configuration. 115
Figure 58 – Bridges with poor VLAN configuration . 116
Figure 59 – Bridges with traffic segmentation through VLAN configuration . 118
Figure 60 – Station bus separated into multicast domains by voltage level . 119
Figure 61 – Multicast traffic on an RSTP ring . 120
Figure 62 – RSTP station bus and HSR ring . 121
Figure 63 – RSTP station bus and HSR process bus . 121
Figure 64 – Clock synchronization channels . 129
Figure 65 – 1 PPS synchronisation . 130
Figure 66 – SNTP clock synchronization and delay measurement . 131

– 8 – TR 61850-90-4 © IEC:2013(E)
Figure 67 – PTP elements . 133
Figure 68 – PTP one-step clock synchronization and delay measurement . 134
Figure 69 – PTP two-step clock synchronization and delay measurement . 136
Figure 70 – Clocks in a PRP network coupled by BCs with an HSR ring . 139
Figure 71 – C37.238-specific TLV . 141
Figure 72 – Hierarchy of clocks . 142
Figure 73 – Quality assurance stages (copied from IEC 61850-4) . 145
Figure 74 – Test set-up for verification test . 147
Figure 75 – Multiport device model . 153
Figure 76 – Linking of bridge objects . 154
Figure 77 – Clock model . 156
Figure 78 – Linking of clock objects . 157
Figure 79 – Class diagram LogicalNodes_90_4::LogicalNodes_90_4 . 158
Figure 80 – Class diagram LNGroupL::LNGroupLExt . 159
Figure 81 – Class diagram LNGroupL::LNGroupLNew . 160
Figure 82 – Usage of VLAN filtering . 163
Figure 83 – Usage of clock references . 169
Figure 84 – Class diagram DetailedDiagram::DOEnums_90_4 . 175
Figure 85 – Class diagram CommonDataClasses_90_4::CommonDataClasses_90_4 . 176
Figure 86 – Class diagram CDCStatusInfo::CDCStatusInfo . 177
Figure 87 – Class diagram CDCStatusSet::CDCStatusSet . 180
Figure 88 – Four-port bridge . 189
Figure 89 – Simple IED with PTP but no LLDP support . 199
Figure 90 – RedBox with LLDP but no PTP . 207
Figure A.1 – Preconditions for the process bus configuration example . 215
Figure B.1 – First Ethernet-based Transba substation automation network . 218
Figure B.2 – Transba SAS architecture . 219
Figure B.3 – Transener substation automation network . 220
Figure B.4 – Transener SAS architecture – ET Esperanza . 222
Figure B.5 – Transener 500 kV architecture – El Morejón . 223
Figure B.6 – 500 kV kiosk topology . 224
Figure B.7 – 33 kV kiosk topology . 225
Figure C.1 – Example HV and LV single line diagram and IEDs . 226
Figure C.2 – HV bay and cabinet module . 228
Figure C.3 – Data network areas . 232
Figure C.4 – Substation LAN topology . 234
Figure C.5 – SAS Gen1 High level traffic flows . 235
Figure C.6 – SCADA & gateway connection . 236
Figure C.7 – Station Core . 236
Figure C.8 – Overall VLANs . 238
Figure C.9 – Three domains. 238
Figure C.10 – One domain per diameter, bus zone and transformer protection . 239
Figure D.1 – Conceptual topology of substation LAN network with redundancy . 245

TR 61850-90-4 © IEC:2013(E) – 9 –
Figure D.2 – Detailed topology of substation LAN with redundancy . 246
Figure D.3 – Original IPv4 Type of Service (ToS) octet . 249
Figure D.4 – Differentiated Services (DiffServ) codepoint field . 249

Table 1 – IEC 61850-5 interface definitions . 28
Table 2 – Example of port ingress setting table . 51
Table 3 – Example of port egress settings . 52
Table 4 – Advantages and drawbacks of VLAN versus multicast filtering . 53
Table 5 – IANA private IP address blocks (copied from RFC 1918) . 58
Table 6 – IP address and mask example . 58
Table 7 – Summary of reference topologies . 62
Table 8 – Reference topologies and redundancy protocols used . 63
Table 9 – Station bus as single bridge . 64
Table 10 – Station bus as hierarchical star . 65
Table 11 – Station bus as dual star . 66
Table 12 – Station bus as ring . 67
Table 13 – Station bus as separated Main 1 and Main 2 protection . 69
Table 14 – Station bus as ring of bridging nodes . 70
Table 15 – Station bus as ring and subrings . 71
Table 16 – Station bus as parallel rings . 73
Table 17 – Station bus as parallel HSR rings . 74
Table 18 – Station bus as ring of rings with RSTP. 75
Table 19 – Station bus as ring of rings with HSR . 76
Table 20 – Station bus as ring and subrings with HSR . 77
Table 21 – Process bus as connection of PIA and PIB . 84
Table 22 – Process bus as single star . 86
Table 23 – Process bus as dual star . 87
Table 24 – Process bus as single bridge . 89
Table 25 – Process bus as separated LANs . 90
Table 26 – Process bus as simple ring . 91
Table 27 – Advantages and drawbacks of physical separation . 92
Table 28 – Advantages and drawbacks of logical separation . 92
Table 29 – Process bus as star to merging units . 93
Table 30 – Connection of station bus to process bus by routers . 95
Table 31 – Connection of station bus to process bus by RedBoxes . 97
Table 32 – Connection of duplicated station bus to process bus by RedBoxes . 98
Table 33 – Example IP address allocation of NET .
...

IEC/TR 61850-90-4 ®
Edition 1.0 2013-08
TECHNICAL
REPORT
colour
inside
Communication networks and systems for power utility automation –
Part 90-4: Network engineering guidelines

IEC/TR 61850-90-4:2013(E)
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 Fax: [phone]

CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
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 corrigenda or an amendment might have been published.

Useful links:
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The advanced search enables you to find IEC publications The world's leading online dictionary of electronic and
by a variety of criteria (reference number, text, technical electrical terms containing more than 30 000 terms and
committee,…). definitions in English and French, with equivalent terms in
It also gives information on projects, replaced and additional languages. Also known as the International
withdrawn publications. Electrotechnical Vocabulary (IEV) on-line.

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IEC/TR 61850-90-4 ®
Edition 1.0 2013-08
TECHNICAL
REPORT
colour
inside
Communication networks and systems for power utility automation –

Part 90-4: Network engineering guidelines

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XH
ICS 33.200 ISBN 978-2-8322-0903-5

– 2 – TR 61850-90-4 © IEC:2013(E)

CONTENTS
FOREWORD . 12

INTRODUCTION . 14

1 Scope . 15

2 Normative references . 16

3 Terms, definitions, abbreviations and conventions . 19

3.1 Terms and definitions . 19

3.2 Abbreviations . 22
3.3 Conventions . 25
3.3.1 Network diagram symbols . 25
3.3.2 Port and link symbols . 26
3.3.3 Bridges symbols . 26
4 Overview of IEC 61850 networks . 27
4.1 Logical allocation of functions and interfaces . 27
4.2 IEC 61850 protocol stack . 29
4.2.1 General . 29
4.2.2 IEC 61850 traffic classes . 29
4.2.3 MMS protocol . 30
4.2.4 GOOSE protocol . 30
4.2.5 SV protocol . 32
4.3 Station bus and process bus . 32
5 Network design checklist . 34
5.1 Design principles . 34
5.2 Engineering flow . 34
5.3 Checklist to be observed . 35
5.3.1 Summary . 35
5.3.2 Environmental issues . 36
5.3.3 EMI immunity . 36
5.3.4 Form factor . 36
5.3.5 Physical media . 36
5.3.6 Substation application and network topology . 36
5.3.7 Redundancy . 37
5.3.8 Reliability, availability, maintainability . 37

5.3.9 Logical data flows and traffic patterns . 37
5.3.10 Latency for different types of traffic . 37
5.3.11 Performance . 37
5.3.12 Network management . 38
5.3.13 Network supervision . 38
5.3.14 Time synchronization and accuracy . 38
5.3.15 Remote connectivity . 38
5.3.16 Cyber security . 38
5.3.17 Scalability, upgradeability and future-proof . 39
5.3.18 Testing . 39
5.3.19 Cost . 39
6 Ethernet technology for substations . 39
6.1 Ethernet subset for substation automation . 39
6.2 Topology . 39

TR 61850-90-4 © IEC:2013(E) – 3 –

6.3 Physical layer . 41

6.3.1 Data rate and medium . 41

6.3.2 Full-duplex communication and auto-negotiation . 41

6.3.3 Copper cabling at 100 Mbit/s . 41

6.3.4 Optical cabling at 100 Mbit/s (100BASE-FX) . 42

6.3.5 Optical cabling at 1 Gbit/s (1000BASE-LX) . 44

6.3.6 Copper cabling at 1 Gbit/s . 44

6.4 Link layer . 44

6.4.1 Unicast and multicast MAC addresses . 44

6.4.2 Link layer and bridges . 45

6.4.3 Bridging nodes . 45
6.4.4 Loop prevention and RSTP . 45
6.4.5 Traffic control in the bridges . 47
6.4.6 Unicast MAC address filtering . 47
6.4.7 Multicast MAC address filtering . 47
6.4.8 Virtual LANs (VLANS) traffic control . 48
6.4.9 Comparison VLAN versus multicast filtering. 53
6.4.10 Layer 2 redundancy protocols . 53
6.5 Network layer . 57
6.5.1 Internet protocol . 57
6.5.2 IP public and private addresses . 57
6.5.3 Subnet masks . 58
6.5.4 Network address translation . 59
7 Network and substation topologies . 59
7.1 General rule . 59
7.2 Reference topologies and network redundancy. 60
7.3 Reference topologies . 64
7.3.1 Station bus topologies . 64
7.3.2 Process bus and attachment of primary equipment . 77
7.3.3 Station bus and process bus connection . 92
8 Addressing in the substation . 98
8.1 Network IP address plan for substations . 98
8.1.1 General structure . 98
8.1.2 IP address allocation of NET . 99
8.1.3 IP address allocation of BAY . 100

8.1.4 IP address allocation of device . 100
8.1.5 IP address allocation of devices with PRP . 101
8.2 Routers and GOOSE / SV traffic . 101
8.3 Communication outside the substation . 101
9 Application parameters . 102
9.1 MMS parameters . 102
9.2 GOOSE parameters . 102
9.3 SV parameters . 102
10 Performance . 103
10.1 Station bus performance . 103
10.1.1 Logical data flows and traffic patterns . 103
10.1.2 GOOSE traffic estimation . 104
10.1.3 MMS traffic estimation . 104

– 4 – TR 61850-90-4 © IEC:2013(E)

10.1.4 station bus measurements . 105

10.2 Process bus performance . 106

11 Latency . 106

11.1 Application requirements . 106

11.2 Latency requirements for different types of traffic . 107

11.2.1 Latency requirements in IEC 61850-5 . 107

11.2.2 Latencies of physical paths . 107

11.2.3 Latencies of bridges . 107

11.2.4 Latency and hop counts . 108

11.2.5 Network latency budget . 108
11.2.6 Example of traffic delays . 109
11.2.7 Engineering a network for IEC 61850 protection . 109
12 Network traffic control . 110
12.1 Factors that affect performance . 110
12.1.1 Influencing factors . 110
12.1.2 Traffic reduction . 110
12.1.3 Example of traffic reduction scheme . 111
12.1.4 Multicast domains in a combined station bus and process bus
network . 112
12.2 Traffic control by VLANs . 113
12.2.1 Trunk traffic reduction by VLANs . 113
12.2.2 VLAN usage . 114
12.2.3 VLAN handling at the IEDs . 114
12.2.4 Example of correct VLAN configuration . 114
12.2.5 Example of incorrect VLAN configuration . 115
12.2.6 Retaining priority throughout the network. 117
12.2.7 Traffic filtering with VLANs . 117
12.3 Traffic control by multicast filtering . 118
12.3.1 Trunk traffic reduction by multicast filtering . 118
12.3.2 Multicast/VLAN management and redundancy protocol
reconfiguration . 119
12.3.3 Physical topologies and multicast management implications . 119
12.4 Configuration support from tools and SCD files . 122
13 Dependability . 122
13.1 Resiliency requirements . 122

13.2 Availability and reliability requirements . 123
13.3 Recovery time requirements . 123
13.4 Maintainability requirements . 123
13.5 Dependability calculations . 124
13.6 Risk analysis attached to "unwanted events" . 124
14 Time services . 125
14.1 Clock synchronization and accuracy requirements . 125
14.2 Global time sources . 125
14.3 Time scales and leap seconds . 126
14.4 Epoch . 127
14.5 Time scales in IEC 61850 . 127
14.6 Synchronization mechanisms in IEC 61850 . 128
14.6.1 Clock synchronization protocols . 128
14.6.2 1 PPS . 130

TR 61850-90-4 © IEC:2013(E) – 5 –

14.6.3 IRIG-B . 130

14.6.4 NTP/SNTP clock synchronization for IEC 61850-8-1 (station bus) . 130

14.6.5 PTP (IEC 61588) synchronization . 132

14.6.6 PTP clock synchronization and IEC 62439-3:2012 . 137

14.6.7 IEEE C37.238-2011 Power profile . 140

14.7 PTP network engineering . 141

14.7.1 PTP reference clock location . 141

14.7.2 PTP connection of station bus and process bus . 142

14.7.3 Merging units synchronization . 143

15 Network security . 143

16 Network management . 143
16.1 Protocols for network management. 143
16.2 Network management tool . 144
16.3 Network diagnostic tool . 144
17 Remote connectivity . 145
18 Network testing . 145
18.1 Introduction to testing . 145
18.2 Environmental type testing . 146
18.3 Conformance testing . 146
18.3.1 Protocols subject to conformance testing . 146
18.3.2 Integrator acceptance and verification testing . 147
18.3.3 Simple verification test set-up . 147
18.3.4 Simple VLAN handling test . 148
18.3.5 Simple priority tagging test . 148
18.3.6 Simple multicast handling test . 149
18.3.7 Simple RSTP recovery test . 149
18.3.8 Simple HSR test . 150
18.3.9 Simple PRP test . 150
18.3.10 Simple PTP test . 150
18.4 Factory and site acceptance testing . 150
19 IEC 61850 bridge and port object model . 151
19.1 Purpose . 151
19.2 Bridge model . 152
19.2.1 Simple model . 152

19.2.2 Bridge Logical Node linking . 154
19.3 Clock model . 154
19.3.1 IEC 61588 datasets . 154
19.3.2 Clock objects . 155
19.3.3 Simple clock model . 155
19.3.4 Linking of clock objects . 156
19.4 Autogenerated IEC 61850 objects . 157
19.4.1 General . 157
19.4.2 Abbreviated terms used in data object names . 157
19.4.3 Logical nodes . 158
19.4.4 Data semantics . 171
19.4.5 Enumerated data attribute types . 174
19.4.6 SCL enumerations . 176
19.4.7 Common data class specifications . 176

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19.4.8 Enumerated types . 182

19.4.9 SCL enumerations . 183

19.5 Mapping of bridge objects to SNMP . 183

19.5.1 Mapping of LLN0 and LPHD attributes to SNMP . 183

19.5.2 Mapping of LBRI attributes to SNMP for bridges . 184

19.5.3 Mapping of LPCP attributes to SNMP for bridges . 184

19.5.4 Mapping of LPLD attributes to SNMP for bridges . 184

19.5.5 Mapping of HSR/PRP link redundancy entity to SNMP . 185

19.6 Mapping of clock objects to the C37.238 SNMP MIB . 186

19.7 Machine-readable description of the bridge objects . 189

19.7.1 Method and examples . 189
19.7.2 Four-port bridge . 189
19.7.3 Simple IED with PTP . 199
19.7.4 RedBox wit HSR . 206
Annex A (informative) Case study – Process bus configuration for busbar protection
system . 214
Annex B (informative) Case study – Simple Topologies (Transener/Transba,
Argentina) . 218
Annex C (informative) Case study – An IEC 61850 station bus (Powerlink, Australia) . 226
Annex D (informative) Case study – Station bus with VLANs (Trans-Africa, South
Africa) . 242
Bibliography . 263

Figure 1 – Network symbols . 26
Figure 2 – Port symbols . 26
Figure 3 – Bridge symbol as beam . 27
Figure 4 – Bridge symbol as bus . 27
Figure 5 – Levels and logical interfaces in substation automation systems . 28
Figure 6 – IEC 61850 protocol stack . 29
Figure 7 – MMS protocol time/distance chart . 30
Figure 8 – GOOSE protocol time/distance chart . 31
Figure 9 – GOOSE protocol time chart . 32
Figure 10 – Example of SV traffic (4 800 Hz) . 32
Figure 11 – Station bus, process bus and traffic example . 33
Figure 12 – Example of engineering flow . 35
Figure 13 – Ethernet local area network (with redundant links) . 40
Figure 14 – Switch with copper (RJ45) ports) . 40
Figure 15 – RJ45 connector . 42
Figure 16 – LC connector . 43
Figure 17 – Switch with optical fibres (LC connectors) . 44
Figure 18 – RSTP principle . 46
Figure 19 – IEEE 802.3 frame format without and with VLAN tagging. 49
Figure 20 – PRP principle . 54
Figure 21 – HSR principle . 56
Figure 22 – HSR and PRP coupling (multicast) . 57
Figure 23 – Mapping of electrical grid to data network topology . 60

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Figure 24 – Station bus as single bridge . 64

Figure 25 – Station bus as hierarchical star . 65

Figure 26 – Station bus as dual star with PRP . 66

Figure 27 – Station bus as ring of RSTP bridges . 67

Figure 28 – Station bus as separated Main 1 (Bus 1) and Main 2 (Bus 2) LANs . 68

Figure 29 – Station bus as ring of HSR bridging nodes . 70

Figure 30 – Station bus as ring and subrings with RSTP . 71

Figure 31 – Station bus as parallel rings with bridging nodes . 72

Figure 32 – Station bus as parallel HSR rings . 73
Figure 33 – Station bus as hierarchical rings with RSTP bridging nodes . 74
Figure 34 – Station bus as hierarchical rings with HSR bridging nodes . 76
Figure 35 – Station bus as ring and subrings with HSR . 77
Figure 36 – Double busbar bay with directly attached sensors . 78
Figure 37 – Double busbar bay with SAMUs and process bus . 79
Figure 38 – Double busbar bay with ECT/EVTs and process bus . 80
Figure 39 – 1 ½ CB diameter with conventional, non-redundant attachment . 81
Figure 40 – 1 ½ CB diameter with SAMUs and process bus . 82
Figure 41 – 1 ½ CB diameter with ECT/EVT and process bus . 83
Figure 42 – Process bus as connection of PIA and PIB (non-redundant protection). 84
Figure 43 – Process bus as single star (not redundant protection) . 85
Figure 44 – Process bus as dual star . 87
Figure 45 – Process bus as a single bridge (no protection redundancy) . 88
Figure 46 – Process bus as separated LANs for main 1 and main 2 . 90
Figure 47 – Process bus as ring of HSR nodes . 91
Figure 48 – Process bus as star to merging units and station bus as RSTP ring . 93
Figure 49 – Station bus and process bus as rings connected by a router . 95
Figure 50 – Station bus ring and process bus ring with HSR . 96
Figure 51 – Station bus as dual PRP ring and process bus as HSR ring . 98
Figure 52 – Station bus used for the measurements . 105
Figure 53 – Typical traffic (packet/s) on the station bus . 105
Figure 54 – Generic multicast domains . 110

Figure 55 – Traffic patterns . 112
Figure 56 – Multicast domains for a combined process bus and station bus . 113
Figure 57 – Bridges with correct VLAN configuration. 115
Figure 58 – Bridges with poor VLAN configuration . 116
Figure 59 – Bridges with traffic segmentation through VLAN configuration . 118
Figure 60 – Station bus separated into multicast domains by voltage level . 119
Figure 61 – Multicast traffic on an RSTP ring . 120
Figure 62 – RSTP station bus and HSR ring . 121
Figure 63 – RSTP station bus and HSR process bus . 121
Figure 64 – Clock synchronization channels . 129
Figure 65 – 1 PPS synchronisation . 130
Figure 66 – SNTP clock synchronization and delay measurement . 131

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Figure 67 – PTP elements . 133

Figure 68 – PTP one-step clock synchronization and delay measurement . 134

Figure 69 – PTP two-step clock synchronization and delay measurement . 136

Figure 70 – Clocks in a PRP network coupled by BCs with an HSR ring . 139

Figure 71 – C37.238-specific TLV . 141

Figure 72 – Hierarchy of clocks . 142

Figure 73 – Quality assurance stages (copied from IEC 61850-4) . 145

Figure 74 – Test set-up for verification test . 147

Figure 75 – Multiport device model . 153
Figure 76 – Linking of bridge objects . 154
Figure 77 – Clock model . 156
Figure 78 – Linking of clock objects . 157
Figure 79 – Class diagram LogicalNodes_90_4::LogicalNodes_90_4 . 158
Figure 80 – Class diagram LNGroupL::LNGroupLExt . 159
Figure 81 – Class diagram LNGroupL::LNGroupLNew . 160
Figure 82 – Usage of VLAN filtering . 163
Figure 83 – Usage of clock references . 169
Figure 84 – Class diagram DetailedDiagram::DOEnums_90_4 . 175
Figure 85 – Class diagram CommonDataClasses_90_4::CommonDataClasses_90_4 . 176
Figure 86 – Class diagram CDCStatusInfo::CDCStatusInfo . 177
Figure 87 – Class diagram CDCStatusSet::CDCStatusSet . 180
Figure 88 – Four-port bridge . 189
Figure 89 – Simple IED with PTP but no LLDP support . 199
Figure 90 – RedBox with LLDP but no PTP . 207
Figure A.1 – Preconditions for the process bus configuration example . 215
Figure B.1 – First Ethernet-based Transba substation automation network . 218
Figure B.2 – Transba SAS architecture . 219
Figure B.3 – Transener substation automation network . 220
Figure B.4 – Transener SAS architecture – ET Esperanza . 222
Figure B.5 – Transener 500 kV architecture – El Morejón . 223
Figure B.6 – 500 kV kiosk topology . 224

Figure B.7 – 33 kV kiosk topology . 225
Figure C.1 – Example HV and LV single line diagram and IEDs . 226
Figure C.2 – HV bay and cabinet module . 228
Figure C.3 – Data network areas . 232
Figure C.4 – Substation LAN topology . 234
Figure C.5 – SAS Gen1 High level traffic flows . 235
Figure C.6 – SCADA & gateway connection . 236
Figure C.7 – Station Core . 236
Figure C.8 – Overall VLANs . 238
Figure C.9 – Three domains. 238
Figure C.10 – One domain per diameter, bus zone and transformer protection . 239
Figure D.1 – Conceptual topology of substation LAN network with redundancy . 245

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Figure D.2 – Detailed topology of substation LAN with redundancy . 246

Figure D.3 – Original IPv4 Type of Service (ToS) octet . 249

Figure D.4 – Differentiated Services (DiffServ) codepoint field . 249

Table 1 – IEC 61850-5 interface definitions . 28

Table 2 – Example of port ingress setting table . 51

Table 3 – Example of port egress settings . 52

Table 4 – Advantages and drawbacks of VLAN versus multicast filtering . 53

Table 5 – IANA private IP address blocks (copied from RFC 1918) . 58
Table 6 – IP address and mask example . 58
Table 7 – Summary of reference topologies . 62
Table 8 – Reference topologies and redundancy protocols used . 63
Table 9 – Station bus as single bridge . 64
Table 10 – Station bus as hierarchical star . 65
Table 11 – Station bus as dual star . 66
Table 12 – Station bus as ring . 67
Table 13 – Station bus as separated Main 1 and Main 2 protection . 69
Table 14 – Station bus as ring of bridging nodes . 70
Table 15 – Station bus as ring and subrings . 71
Table 16 – Station bus as parallel rings . 73
Table 17 – Station bus as parallel HSR rings . 74
Table 18 – Station bus as ring of rings with RSTP. 75
Table 19 – Station bus as ring of rings with HSR . 76
Table 20 – Station bus as ring and subrings with HSR . 77
Table 21 – Process bus as connection of PIA and PIB . 84
Table 22 – Process bus as single star . 86
Table 23 – Process bus as dual star . 87
Table 24 – Process bus as single bridge . 89
Table 25 – Process bus as separated LANs . 90
Table 26 – Process bus as simple ring . 91
Table 27 – Advantages and drawbacks of physical separation . 92

Table 28 – Advantages and drawbacks of logical separation . 92
Table 29 – Process bus as star to merging units . 93
Table 30 – Connection of station bus to process bus by routers .
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