IEC 62541-4:2011

IEC 62541-4 ®
Edition 1.0 2011-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 4: Services
Architecture unifiée OPC –
Partie 4: Services
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IEC 62541-4 ®
Edition 1.0 2011-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 4: Services
Architecture unifiée OPC –
Partie 4: Services
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XH
ICS 25.040.40; 25.100.01 ISBN 978-2-88912-730-6

– 2 – 62541-4 © IEC:2011
CONTENTS
FOREWORD . 12
INTRODUCTION . 14
1 Scope . 15
2 Normative references . 15
3 Terms, definitions and conventions . 16
3.1 Terms and definitions . 16
3.2 Abbreviations . 16
3.3 Conventions for Service definitions . 17
4 Overview . 18
4.1 Service Set model . 18
4.2 Request/response Service procedures . 21
5 Service Sets . 21
5.1 General . 21
5.2 Service request and response header . 22
5.3 Service results . 22
5.4 Discovery Service Set . 23
5.4.1 Overview . 23
5.4.2 FindServers . 24
5.4.3 GetEndpoints . 26
5.4.4 RegisterServer . 29
5.5 SecureChannel Service Set . 31
5.5.1 Overview . 31
5.5.2 OpenSecureChannel . 33
5.5.3 CloseSecureChannel . 35
5.6 Session Service Set . 35
5.6.1 Overview . 35
5.6.2 CreateSession . 36
5.6.3 ActivateSession . 39
5.6.4 CloseSession . 42
5.6.5 Cancel . 42
5.7 NodeManagement Service Set . 43
5.7.1 Overview . 43
5.7.2 AddNodes. 43
5.7.3 AddReferences . 45
5.7.4 DeleteNodes . 47
5.7.5 DeleteReferences . 48
5.8 View Service Set . 49
5.8.1 Overview . 49
5.8.2 Browse . 49
5.8.3 BrowseNext . 51
5.8.4 TranslateBrowsePathsToNodeIds . 53
5.8.5 RegisterNodes . 55
5.8.6 UnregisterNodes . 56
5.9 Query Service Set . 56

62541-4 © IEC:2011 – 3 –
5.9.1 Overview . 56
5.9.2 Querying Views . 57
5.9.3 QueryFirst . 57
5.9.4 QueryNext . 60
5.10 Attribute Service Set . 61
5.10.1 Overview . 61
5.10.2 Read . 61
5.10.3 HistoryRead . 63
5.10.4 Write . 65
5.10.5 HistoryUpdate . 67
5.11 Method Service Set . 68
5.11.1 Overview . 68
5.11.2 Call . 68
5.12 MonitoredItem Service Set . 70
5.12.1 MonitoredItem model . 70
5.12.2 CreateMonitoredItems . 74
5.12.3 ModifyMonitoredItems . 76
5.12.4 SetMonitoringMode . 78
5.12.5 SetTriggering . 79
5.12.6 DeleteMonitoredItems . 80
5.13 Subscription Service Set . 81
5.13.1 Subscription model . 81
5.13.2 CreateSubscription . 88
5.13.3 ModifySubscription . 89
5.13.4 SetPublishingMode . 90
5.13.5 Publish . 91
5.13.6 Republish . 93
5.13.7 TransferSubscriptions . 93
5.13.8 DeleteSubscriptions . 95
6 Service behaviours . 96
6.1 Security . 96
6.1.1 Overview . 96
6.1.2 Obtaining and Installing an Application Instance Certificate . 96
6.1.3 Obtaining and installing a Software Certificate . 97
6.1.4 Determining if a Certificate is Trusted . 99
6.1.5 Validating a Software Certificate . 101
6.1.6 Creating a SecureChannel . 101
6.1.7 Creating a Session . 103
6.1.8 Impersonating a User . 104
6.2 Auditing . 104
6.2.1 Overview . 104
6.2.2 General audit logs . 104
6.2.3 General audit Events . 105
6.2.4 Auditing for Discovery Service Set . 105
6.2.5 Auditing for SecureChannel Service Set . 105
6.2.6 Auditing for Session Service Set . 105
6.2.7 Auditing for NodeManagement Service Set . 106
6.2.8 Auditing for Attribute Service Set . 106
6.2.9 Auditing for Method Service Set . 106

– 4 – 62541-4 © IEC:2011
6.2.10 Auditing for View, Query, MonitoredItem and Subscription Service
Set . 107
6.3 Redundancy . 107
6.3.1 Redundancy overview . 107
6.3.2 Server redundancy overview . 107
6.3.3 Client redundancy. 109
7 Common parameter type definitions . 110
7.1 ApplicationDescription . 110
7.2 ApplicationInstanceCertificate . 110
7.3 BrowseResult . 111
7.4 ContentFilter . 111
7.4.1 ContentFilter structure . 111
7.4.2 ContentFilterResult . 112
7.4.3 FilterOperator . 113
7.4.4 FilterOperand parameters . 119
7.5 Counter . 120
7.6 ContinuationPoint . 121
7.7 DataValue . 121
7.7.1 General . 121
7.7.2 PicoSeconds . 121
7.7.3 SourceTimestamp . 122
7.7.4 ServerTimestamp . 122
7.7.5 StatusCode assigned to a value . 123
7.8 DiagnosticInfo . 123
7.9 EndpointDescription . 124
7.10 ExpandedNodeId . 124
7.11 ExtensibleParameter . 125
7.12 Index . 125
7.13 IntegerId. 125
7.14 MessageSecurityMode . 125
7.15 MonitoringParameters . 125
7.16 MonitoringFilter parameters . 126
7.16.1 Overview . 126
7.16.2 DataChangeFilter . 126
7.16.3 EventFilter . 127
7.16.4 AggregateFilter . 129
7.17 MonitoringMode . 131
7.18 NodeAttributes parameters . 131
7.18.1 Overview . 131
7.18.2 ObjectAttributes parameter . 132
7.18.3 VariableAttributes parameter . 132
7.18.4 MethodAttributes parameter . 133
7.18.5 ObjectTypeAttributes parameter . 133
7.18.6 VariableTypeAttributes parameter . 133
7.18.7 ReferenceTypeAttributes parameter . 134
7.18.8 DataTypeAttributes parameter . 134
7.18.9 ViewAttributes parameter . 134
7.19 NotificationData parameters . 135
7.19.1 Overview . 135

62541-4 © IEC:2011 – 5 –
7.19.2 DataChangeNotification parameter . 135
7.19.3 EventNotificationList parameter . 136
7.19.4 StatusChangeNotification parameter. 136
7.20 NotificationMessage . 136
7.21 NumericRange . 137
7.22 QueryDataSet . 138
7.23 ReadValueId . 138
7.24 ReferenceDescription . 139
7.25 RelativePath . 139
7.26 RequestHeader . 140
7.27 ResponseHeader . 141
7.28 ServiceFault . 141
7.29 SessionAuthenticationToken . 141
7.30 SignatureData . 143
7.31 SignedSoftwareCertificate . 143
7.32 SoftwareCertificate . 143
7.33 StatusCode . 144
7.33.1 General . 144
7.33.2 Common StatusCodes . 146
7.34 TimestampsToReturn . 148
7.35 UserIdentityToken parameters . 148
7.35.1 Overview . 148
7.35.2 AnonymousIdentityToken. 149
7.35.3 UserNameIdentityToken . 149
7.35.4 X509IdentityTokens . 150
7.35.5 IssuedIdentityToken . 150
7.36 UserTokenPolicy . 151
7.37 ViewDescription . 151
Annex A (informative) BNF definitions . 152
Annex B (informative) Content Filter and Query Examples . 154
Bibliography . 172

Figure 1 – Discovery Service Set . 18
Figure 2 – SecureChannel Service Set . 18
Figure 3 – Session Service Set . 19
Figure 4 – NodeManagement Service Set . 19
Figure 5 – View Service Set . 19
Figure 6 – Attribute Service Set . 20
Figure 7 – Method Service Set . 20
Figure 8 – MonitoredItem and Subscription Service Sets . 21
Figure 9 – Discovery process . 24
Figure 10 – Using a Gateway Server . 28
Figure 11 – Registration process – Manually launched servers . 29
Figure 12 – Registration process – Automatically Launched Servers . 30
Figure 13 – SecureChannel and Session Services . 32
Figure 14 – Multiplexing Users on a Session . 37

– 6 – 62541-4 © IEC:2011
Figure 15 – MonitoredItem Model . 70
Figure 16 – Typical delay in change detection. 72
Figure 17 – Triggering Model . 74
Figure 18 – Obtaining and installing an Application Instance Certificate . 97
Figure 19 – Obtaining and Installing a Software Certificate . 98
Figure 20 – Determining if a Application Instance Certificate is Trusted . 101
Figure 21 – Establishing a SecureChannel . 102
Figure 22 – Establishing a Session . 103
Figure 23 – Impersonating a User . 104
Figure 24 – Transparent Redundancy setup . 108
Figure 25 – Non-Transparent Redundancy setup . 108
Figure 26 – Redundancy mode . 109
Figure 27 – Logical layers of a Server . 142
Figure 28 – Obtaining a SessionAuthenticationToken . 142
Figure B.1 – Filter Logic Tree Example . 154
Figure B.2 – Filter Logic Tree Example . 155
Figure B.3 – Example Type Nodes . 157
Figure B.4 – Example Instance Nodes . 158
Figure B.5 – Example 1 Filter . 159
Figure B.6 – Example 2 Filter Logic Tree . 160
Figure B.7 – Example 3 Filter Logic Tree . 162
Figure B.8 – Example 4 Filter Logic Tree . 164
Figure B.9 – Example 5 Filter Logic Tree . 165
Figure B.10 – Example 6 Filter Logic Tree . 166
The corresponding ContentFilter is illustrated in . 168
Figure B.11 – Example 7 Filter Logic Tree . 168
Figure B.12 – Example 8 Filter Logic Tree . 169
Figure 13 – Example 9 Filter Logic Tree . 171

Table 1 – Service Definition Table . 17
Table 2 – Parameter Types defined in IEC 62541-3 . 17
Table 3 – FindServers Service Parameters . 26
Table 4 – GetEndpoints Service Parameters . 28
Table 5 – RegisterServer Service Parameters . 31
Table 6 – RegisterServer Service Result Codes . 31
Table 7 – OpenSecureChannel Service Parameters . 34
Table 8 – OpenSecureChannel Service Result Codes . 35
Table 9 – CloseSecureChannel Service Parameters . 35
Table 10 – CloseSecureChannel Service Result Codes . 35
Table 11 – CreateSession Service Parameters . 38
Table 12 – CreateSession Service Result Codes . 39
Table 13 – ActivateSession Service Parameters . 41
Table 14 – ActivateSession Service Result Codes . 42

62541-4 © IEC:2011 – 7 –
Table 15 – CloseSession Service Parameters . 42
Table 16 – CloseSession Service Result Codes . 42
Table 17 – Cancel Service Parameters . 43
Table 18 – AddNodes Service Parameters . 44
Table 19 – AddNodes Service Result Codes . 44
Table 20 – AddNodes Operation Level Result Codes . 45
Table 21 – AddReferences Service Parameters . 46
Table 22 – AddReferences Service Result Codes . 46
Table 23 – AddReferences Operation Level Result Codes . 46
Table 24 – DeleteNodes Service Parameters . 47
Table 25 – DeleteNodes Service Result Codes . 47
Table 26 – DeleteNodes Operation Level Result Codes . 48
Table 27 – DeleteReferences Service Parameters . 48
Table 28 – DeleteReferences Service Result Codes . 49
Table 29 – DeleteReferences Operation Level Result Codes . 49
Table 30 – Browse Service Parameters . 50
Table 31 – Browse Service Result Codes . 51
Table 32 – Browse Operation Level Result Codes . 51
Table 33 – BrowseNext Service Parameters . 52
Table 34 – BrowseNext Service Result Codes . 52
Table 35 – BrowseNext Operation Level Result Codes . 53
Table 36 – TranslateBrowsePathsToNodeIds Service Parameters . 54
Table 37 – TranslateBrowsePathsToNodeIds Service Result Codes . 54
Table 38 – TranslateBrowsePathsToNodeIds Operation Level Result Codes . 55
Table 39 – RegisterNodes Service Parameters . 55
Table 40 – RegisterNodes Service Result Codes . 56
Table 41 – UnregisterNodes Service Parameters . 56
Table 42 – UnregisterNodes Service Result Codes . 56
Table 43 – QueryFirst Request Parameters . 58
Table 44 – QueryFirst Response Parameters . 59
Table 45 – QueryFirst Service Result Codes . 60
Table 46 – QueryFirst Operation Level Result Codes . 60
Table 47 – QueryNext Service Parameters . 61
Table 48 – QueryNext Service Result Codes . 61
Table 49 – Read Service Parameters . 62
Table 50 – Read Service Result Codes . 62
Table 51 – Read Operation Level Result Codes . 63
Table 52 – HistoryRead ServiceParameters . 63
Table 53 – HistoryRead Service Result Codes . 64
Table 54 – HistoryRead Operation Level Result Codes . 65
Table 55 – Write Service Parameters . 66
Table 56 – Write Service Result Codes . 66
Table 57 – Write Operation Level Result Codes . 67

– 8 – 62541-4 © IEC:2011
Table 58 – HistoryUpdate Service Parameters . 67
Table 59 – HistoryUpdate Service Result Codes . 68
Table 60 – HistoryUpdate Operation Level Result Codes . 68
Table 61 – Call Service Parameters . 69
Table 62 – Call Service Result Codes . 69
Table 63 – Call Operation Level Result Codes . 70
Table 64 – CreateMonitoredItems Service Parameters . 75
Table 65 – CreateMonitoredItems Service Result Codes . 76
Table 66 – CreateMonitoredItems Operation Level Result Codes . 76
Table 67 – ModifyMonitoredItems Service Parameters . 77
Table 68 – ModifyMonitoredItems Service Result Codes . 77
Table 69 – ModifyMonitoredItems Operation Level Result Codes . 78
Table 70 – SetMonitoringMode Service Parameters . 78
Table 71 – SetMonitoringMode Service Result Codes . 78
Table 72 – SetMonitoringMode Operation Level Result Codes . 79
Table 73 – SetTriggering Service Parameters . 79
Table 74 – SetTriggering Service Result Codes . 79
Table 75 – SetTriggering Operation Level Result Codes . 80
Table 76 – DeleteMonitoredItems Service Parameters . 80
Table 77 – DeleteMonitoredItems Service Result Codes . 80
Table 78 – DeleteMonitoredItems Operation Level Result Codes . 81
Table 79 – Subscription States . 83
Table 80 – Subscription State Table . 84
Table 81 – State variables and parameters . 86
Table 82 – Functions . 87
Table 83 – CreateSubscription Service Parameters . 88
Table 84 – CreateSubscription Service Result Codes . 89
Table 85 – ModifySubscription Service Parameters . 89
Table 86 – ModifySubscription Service Result Codes . 90
Table 87 – SetPublishingMode Service Parameters . 90
Table 88 – SetPublishingMode Service Result Codes . 90
Table 89 – SetPublishingMode Operation Level Result Codes . 91
Table 90 – Publish Service Parameters . 92
Table 91 – Publish Service Result Codes . 92
Table 92 – Publish Operation Level Result Codes . 92
Table 93 – Republish Service Parameters . 93
Table 94 – Republish Service Result Codes . 93
Table 95 – TransferSubscriptions Service Parameters . 94
Table 96 – TransferSubscriptions Service Result Codes . 94
Table 97 – TransferSubscriptions Operation Level Result Codes . 94
Table 98 – DeleteSubscriptions Service Parameters . 95
Table 99 – DeleteSubscriptions Service Result Codes . 95
Table 100 – DeleteSubscriptions Operation Level Result Codes . 95

62541-4 © IEC:2011 – 9 –
Table 101 – Certificate Validation Steps . 100
Table 102 – Redundancy failover actions . 109
Table 103 – ApplicationDescription . 110
Table 104 – ApplicationInstanceCertificate . 111
Table 105 – BrowseResult . 111
Table 106 – ContentFilter Structure . 112
Table 107 – ContentFilterResult Structure . 112
Table 108 – ContentFilterResult Result Codes . 112
Table 109 – ContentFilterResult Operand Result Codes . 112
Table 110 – Basic FilterOperator Definition . 113
Table 111 – Complex FilterOperator Definition . 115
Table 112 – Wildcard characters . 116
Table 113 – Conversion Rules . 117
Table 114 – Data Precedence Rules . 118
Table 115 – Logical AND Truth Table . 118
...