IEC 62541-14:2020

IEC 62541-14 ®
Edition 1.0 2020-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 14: PubSub
Architecture unifiée OPC –
Partie 14: PubSub
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IEC 62541-14 ®
Edition 1.0 2020-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 14: PubSub
Architecture unifiée OPC –
Partie 14: PubSub
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40; 35.100.05 ISBN 978-2-8322-8577-0

– 2 – IEC 62541-14:2020 © IEC 2020
CONTENTS
FOREWORD . 10
1 Scope . 12
2 Normative references . 12
3 Terms, definitions and abbreviated terms . 13
3.1 Terms and definitions . 13
3.2 Abbreviated terms . 14
4 Overview . 14
4.1 Fields of application . 14
4.2 Abstraction layers . 15
4.3 Decoupling by use of middleware . 15
4.4 Synergy of models . 16
5 PubSub Concepts . 16
5.1 General . 16
5.2 DataSet . 17
5.2.1 General . 17
5.2.2 DataSetClass . 18
5.2.3 DataSetMetaData . 18
5.3 Messages . 19
5.3.1 General . 19
5.3.2 DataSetMessage field . 20
5.3.3 DataSetMessage . 20
5.3.4 NetworkMessage . 21
5.3.5 Message security . 21
5.3.6 Transport security . 22
5.3.7 SecurityGroup . 22
5.4 Entities . 22
5.4.1 Publisher . 22
5.4.2 Subscriber . 25
5.4.3 Security Key Service . 26
5.4.4 Message Oriented Middleware . 29
6 PubSub communication parameters . 33
6.1 Overview. 33
6.2 Common Configuration Parameters. 34
6.2.1 PubSubState State Machine . 34
6.2.2 PublishedDataSet parameters . 36
6.2.3 DataSetWriter Parameters . 44
6.2.4 Shared PubSubGroup Parameters . 48
6.2.5 WriterGroup parameters . 50
6.2.6 PubSubConnection Parameters . 52
6.2.7 ReaderGroup parameters . 55
6.2.8 DataSetReader Parameters . 56
6.2.9 SubscribedDataSet Parameters . 60
6.2.10 Information flow and status handling . 63
6.2.11 PubSubConfigurationDataType . 65
6.3 Message mapping configuration parameters . 66
6.3.1 UADP message mapping . 66

6.3.2 JSON message mapping . 74
6.4 Transport Protocol mapping configuration parameters . 77
6.4.1 Datagram Transport Protocol . 77
6.4.2 Broker Transport Protocol . 78
7 PubSub mappings . 83
7.1 General . 83
7.2 Message mappings . 83
7.2.1 General . 83
7.2.2 UADP message mapping . 83
7.2.3 JSON message mapping . 99
7.3 Transport Protocol Mappings . 102
7.3.1 General . 102
7.3.2 OPC UA UDP . 102
7.3.3 OPC UA Ethernet . 103
7.3.4 AMQP . 104
7.3.5 MQTT . 109
8 PubSub security key service model . 111
8.1 Overview. 111
8.2 PublishSubscribe Object . 111
8.3 PubSubKeyServiceType . 112
8.4 GetSecurityKeys method . 112
8.5 GetSecurityGroup method . 114
8.6 SecurityGroupType . 115
8.7 SecurityGroupFolderType . 116
8.8 AddSecurityGroup Method . 116
8.9 RemoveSecurityGroup Method . 117
9 PubSub configuration model . 117
9.1 Common configuration model . 117
9.1.1 General . 117
9.1.2 Configuration behaviours . 120
9.1.3 Types for the PublishSubscribe Object . 120
9.1.4 Published DataSet Model. 125
9.1.5 Connection Model . 141
9.1.6 Group Model . 145
9.1.7 DataSetWriter Model . 153
9.1.8 DataSetReader Model . 155
9.1.9 Subscribed DataSet Model . 160
9.1.10 PubSub Status Object. 163
9.1.11 PubSub Diagnostics Objects . 164
9.1.12 PubSub Status Events . 173
9.2 Message Mapping Configuration Model . 175
9.2.1 UADP Message Mapping . 175
9.2.2 JSON Message Mapping . 177
9.3 Transport Protocol Mapping Configuration Model . 178
9.3.1 Datagram Transport Protocol Mapping . 178
9.3.2 Broker Transport Protocol Mapping. 179
Annex A (normative) Common types . 182
A.1 DataType Schema Header structures . 182

– 4 – IEC 62541-14:2020 © IEC 2020
A.1.1 DataTypeSchemaHeader . 182
A.1.2 DataTypeDescription . 183
A.1.3 StructureDescription . 183
A.1.4 EnumDescription . 184
A.1.5 SimpleTypeDescription . 184
A.2 UABinaryFileDataType . 184
A.3 NetworkAddress Model . 185
A.3.1 NetworkAddressType . 185
A.3.2 NetworkAddressUrlType . 186
Annex B (informative) Client Server vs. Publish Subscribe . 187
B.1 Overview. 187
B.2 Client Server Subscriptions . 187
B.3 Publish-Subscribe . 188
B.4 Synergy of models . 189

Figure 1 – Publish Subscribe Model overview . 15
Figure 2 – Publisher and Subscriber entities . 17
Figure 3 – DataSet in the process of publishing . 18
Figure 4 – OPC UA PubSub message layers . 20
Figure 5 – Publisher details . 23
Figure 6 – Publisher message sending sequence . 24
Figure 7 – Subscriber details . 25
Figure 8 – Subscriber message reception sequence . 26
Figure 9 – SecurityGroup management sequence . 27
Figure 10 – Handshake used to pull keys from SKS . 28
Figure 11 – Handshake used to push keys to Publishers and Subscribers . 28
Figure 12 – Handshake with a Security Key Service . 29
Figure 13 – PubSub using network infrastructure . 30
Figure 14 – UDP Multicast overview . 30
Figure 15 – PubSub using broker . 31
Figure 16 – Broker overview . 32
Figure 17 – PubSub component overview . 33
Figure 18 – PubSub mapping specific parameters overview . 34
Figure 19 – PubSub component state dependencies . 35
Figure 20 – PubSubState state machine . 35
Figure 21 – PubSub Information Flow dependency to field representation . 45
Figure 22 – PubSub information flow . 64
Figure 23 – Start of the periodic publisher execution . 67
Figure 24 – Timing offsets in a PublishingInterval . 67
Figure 25 – DataSetOrdering and MaxNetworkMessageSize . 68
Figure 26 – PublishingOffset options for multiple NetworkMessages . 70
Figure 27 – UADP NetworkMessage . 84
Figure 28 – UADP DataSet payload . 90
Figure 29 – DataSetMessage header structure . 91
Figure 30 – Data Key Frame DataSetMessage data . 93

Figure 31 – Data Delta Frame DataSetMessage . 94
Figure 32 – Event DataSetMessage . 95
Figure 33 – KeepAlive message . 95
Figure 34 – PublishSubscribe Object Types overview . 111
Figure 35 – PubSub configuration model overview . 118
Figure 36 – PubSub example Objects . 119
Figure 37 – PubSub information flow . 119
Figure 38 – PublishSubscribe Object Types overview . 121
Figure 39 – Published DataSet overview . 125
Figure 40 – PubSubConnectionType overview . 142
Figure 41 – PubSubGroupType overview . 145
Figure 42 – DataSet Writer Model Overview . 153
Figure 43 – DataSet Reader Model overview . 155
Figure 44 – PubSub Diagnostics overview . 165
Figure 45 – PubSubDiagnosticsCounterType . 165
Figure B.1 – Subscriptions in OPC UA Client Server Model . 188
Figure B.2 – Publish Subscribe Model Overview . 189

Table 1 – PubSubState values . 35
Table 2 – PubSubState state machine . 36
Table 3 – DataSetMetaDataType structure . 36
Table 4 – DataSetMetaDataType definition . 37
Table 5 – FieldMetaData structure . 37
Table 6 – DataSetFieldFlags values . 39
Table 7 – DataSetFieldFlags definition . 39
Table 8 – ConfigurationVersionDataType structure . 40
Table 9 – PublishedDataSetDataType structure . 41
Table 10 – PublishedDataSetSourceDataType definition . 41
Table 11 – PublishedVariableDataType structure . 42
Table 12 – PublishedDataItemsDataType structure . 43
Table 13 – PublishedEventsDataType structure . 43
Table 14 – DataSetFieldContentMask values . 44
Table 15 – DataSetFieldContentMask definition . 45
Table 16 – DataSetMessage field representation options . 46
Table 17 – DataSetWriterDataType structure . 47
Table 18 – DataSetWriterTransportDataType definition . 47
Table 19 – DataSetWriterMessageDataType structure . 48
Table 20 – PubSubGroupDataType structure . 49
Table 21 – PubSubGroupDataType definition . 49
Table 22 – WriterGroupDataType structure . 51
Table 23 – WriterGroupDataType definition . 51
Table 24 – WriterGroupTransportDataType definition . 52
Table 25 – WriterGroupMessageDataType structure . 52

– 6 – IEC 62541-14:2020 © IEC 2020
Table 26 – PubSubConnectionDataType structure . 53
Table 27 – ConnectionTransportDataType definition . 54
Table 28 – NetworkAddressDataType structure . 54
Table 29 – NetworkAddressDataType definition . 54
Table 30 – NetworkAddressUrlDataType structure . 54
Table 31 – NetworkAddressUrlDataType definition. 55
Table 32 – ReaderGroupDataType structure . 55
Table 33 – ReaderGroupDataType definition. 55
Table 34 – ReaderGroupTransportDataType definition . 56
Table 35 – ReaderGroupMessageDataType structure . 56
Table 36 – DataSetReaderDataType structure . 59
Table 37 – DataSetReaderTransportDataType structure . 59
Table 38 – DataSetReaderTransportDataType definition . 60
Table 39 – DataSetReaderMessageDataType structure . 60
Table 40 – DataSetReaderMessageDataType definition . 60
Table 41 – SubscribedDataSetDataType structure . 60
Table 42 – SubscribedDataSetDataType Definition . 61
Table 43 – TargetVariablesDataType structure . 61
Table 44 – FieldTargetDataType structure . 62
Table 45 – OverrideValueHandling values . 63
Table 46 – SubscribedDataSetMirrorDataType structure . 63
Table 47 – Source to message input mapping . 64
Table 48 – Message output to target mapping . 65
Table 49 – PubSubConfigurationDataType structure . 65
Table 50 – PubSubConfiguration file content . 66
Table 51 – DataSetOrderingType values . 68
Table 52 – UadpNetworkMessageContentMask values . 69
Table 53 – UadpNetworkMessageContentMask definition . 69
Table 54 – UadpWriterGroupMessageDataType structure . 71
Table 55 – UadpDataSetMessageContentMask values . 71
Table 56 – UadpDataSetMessageContentMask definition . 72
Table 57 – UadpDataSetWriterMessageDataType structure . 73
Table 58 – UadpDataSetReaderMessageDataType structure . 74
Table 59 – JsonNetworkMessageContentMask values . 75
Table 60 – JsonNetworkMessageContentMask definition . 75
Table 61 – JsonWriterGroupMessageDataType structure . 75
Table 62 – JsonDataSetMessageContentMask values . 76
Table 63 – JsonDataSetMessageContentMask definition . 76
Table 64 – JsonDataSetWriterMessageDataType structure . 76
Table 65 – JsonDataSetReaderMessageDataType structure . 77
Table 66 – DatagramConnectionTransportDataType structure . 77
Table 67 – DatagramWriterGroupTransportDataType structure . 78
Table 68 – BrokerConnectionTransportDataType structure . 79

Table 69 – BrokerTransportQualityOfService values . 80
Table 70 – BrokerWriterGroupTransportDataType structure . 80
Table 71 – BrokerDataSetWriterTransportDataType structure . 82
Table 72 – BrokerDataSetReaderTransportDataType structure . 83
Table 73 – UADP NetworkMessage . 84
Table 74 – Layout of the key data for UADP message security . 87
Table 75 – Layout of the MessageNonce for AES-CTR . 88
Table 76 – Layout of the counter block for UADP message security . 88
Table 77 – Chunked NetworkMessage payload header . 89
Table 78 – Chunked NetworkMessage payload fields . 89
Table 79 – UADP DataSet payload header . 90
Table 80 – UADP DataSet payload . 91
Table 81 – DataSetMessage header structure . 92
Table 82 – Data Key Frame DataSetMessage structure . 93
Table 83 – Data Delta Frame DataSetMessage structure . 94
Table 84 – Event DataSetMessage structure . 95
Table 85 – Discovery request header structure . 97
Table 86 – Publisher information request message structure . 97
Table 87 – Discovery response header structure. 98
Table 88 – Publisher Endpoints message structure . 98
Table 89 – DataSetMetaData message structure . 98
Table 90 – DataSetWriter configuration message structure . 99
Table 91 – JSON NetworkMessage definition . 99
Table 92 – JSON DataSetMessage definition . 101
Table 93 – JSON DataSetMetaData definition . 102
Table 94 – UADP message transported over UDP . 103
Table 95 – UADP message transported over Ethernet . 104
Table 96 – AMQP standard header fields . 106
Table 97 – OPC UA AMQP standard header QualifiedName Name mappings . 107
Table 98 – OPC UA AMQP header field conversion rules . 108
Table 99 – PublishSubscribe Object definition . 112
Table 100 – PubSubKeyServiceType definition . 112
Table 101 – SecurityGroupType definition . 115
Table 102 – SecurityGroupFolderType definition . 116
Table 103 – PublishSubscribeType definition . 122
Table 104 – HasPubSubConnection ReferenceType . 125
Table 105 – PublishedDataSetType definition . 126
Table 106 – ExtensionFieldsType definition . 127
Table 107 – Well-Known Extension Field Names . 128
Table 108 – DataSetToWriter ReferenceType . 129
Table 109 – PublishedDataItemsType definition . 130
Table 110 – PublishedEventsType definition . 133
Table 111 – DataSetFolderType definition . 134

– 8 – IEC 62541-14:2020 © IEC 2020
Table 112 – PubSubConnectionType definition . 142
Table 113 – ConnectionTransportType definition . 145
Table 114 – PubSubGroupType definition . 146
Table 115 – WriterGroupType definition . 147
Table 116 – HasDataSetWriter ReferenceType . 149
Table 117 – WriterGroupTransportType definition . 149
Table 118 – WriterGroupMessageType definition . 150
Table 119 – ReaderGroupType definition . 150
Table 120 – HasDataSetReader ReferenceType . 152
Table 121 – ReaderGroupTransportType definition . 152
Table 122 – ReaderGroupMessageType Definition . 152
Table 123 – DataSetWriterType definition . 153
Table 124 – DataSetWriterTransportType definition . 154
Table 125 – DataSetWriterMessageType definition . 154
Table 126 – DataSetReaderType definition . 156
Table 127 – DataSetReaderTransportType definition . 157
Table 128 – DataSetReaderMessageType definition . 158
Table 129 – SubscribedDataSetType definition . 160
Table 130 – TargetVariablesType definition . 160
Table 131 – SubscribedDataSetMirrorType definition . 162
Table 132 – PubSubStatusType definition . 163
Table 133 – Status Object definition . 164
Table 134 – PubSubDiagnosticsType . 166
Table 135 – Counters for PubSubDiagnosticsType . 166
Table 136 – DiagnosticsLevel Values . 167
Table 137 – PubSubDiagnosticsCounterType . 168
Table 138 – PubSubDiagnosticsCounterClassification Values . 168
Table 139 – PubSubDiagnosticsRootType . 169
Table 140 – LiveValues for PubSubDiagnosticsRootType . 169
Table 141 – PubSubDiagnosticsConnectionType . 169
Table 142 – LiveValues for PubSubDiagnosticsConnectionType . 170
Table 143 – PubSubDiagnosticsWriterGroupType . 170
Table 144 – Counters for PubSubDiagnosticsWriterGroupType . 170
Table 145 – LiveValues for PubSubDiagnosticsWriterGroupType . 170
Table 146 – PubSubDiagnosticsReaderGroupType . 171
Table 147 – Counters for PubSubDiagnosticsReaderGroupType . 171
Table 148 – LiveValues for PubSubDiagnosticsReaderGroupType . 171
Table 149 – PubSubDiagnosticsDataSetWriterType . 172
Table 150 – Counters for PubSubDiagnosticsDataSetWriterType . 172
Table 151 – LiveValues for PubSubDiagnosticsDataSetWriterType . 172
Table 152 – PubSubDiagnosticsDataSetReaderType . 172
Table 153 – Counters for PubSubDiagnosticsDataSetReaderType . 173
Table 154 – LiveValues for PubSubDiagnosticsDataSetReaderType . 173

Table 155 – PubSubStatusEventType definition . 173
Table 156 – PubSubTransportLimitsExceedEventType definition . 174
Table 157 – PubSubCommunicationFailureEventType definition . 174
Table 158 – UadpWriterGroupMessageType definition . 175
Table 159 – UadpDataSetWriterMessageType definition . 176
Table 160 – UadpDataSetReaderMessageType definition . 176
Table 161 – JsonWriterGroupMessageType Definition . 177
Table 162 – JsonDataSetWriterMessageType definition . 177
Table 163 – JsonDataSetReaderMessageType definition . 178
Table 164 – DatagramConnectionTransportType definition . 178
Table 165 – DatagramWriterGroupTransportType definition . 178
Table 166 – BrokerConnectionTransportType definition . 179
Table 167 – BrokerWriterGroupTransportType definition . 179
Table 168 – BrokerDataSetWriterTransportType definition . 180
Table 169 – Broker Writer well-known extension field names . 180
Table 170 – BrokerDataSetReaderTransportType definition . 181
Table A.1 – DataTypeSchemaHeader structure . 182
Table A.2 – DataTypeSchemaHeader definition . 182
Table A.3 – DataTypeDescription structure . 183
Table A.4 – DataTypeDescription definition . 183
Table A.5 – Stru
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