EN 62351-7:2017

SLOVENSKI STANDARD
01-marec-2018
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Power systems management and associated information exchange - Data and
communications security - Part 7: Network and System management (NSM) data object
models
Ta slovenski standard je istoveten z: EN 62351-7:2017
ICS:
29.240.30 Krmilna oprema za Control equipment for electric
elektroenergetske sisteme power systems
35.240.50 Uporabniške rešitve IT v IT applications in industry
industriji
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 62351-7
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2017
ICS 33.200
English Version
Power systems management and associated information
exchange - Data and communications security -
Part 7: Network and System Management (NSM) data object
models
(IEC 62351-7:2017)
Gestion des systèmes d'alimentation et échange Datenmodelle, Schnittstellen und Informationsaustausch für
d'informations associées - Sécurité des données et des Planung und Betrieb von Energieversorgungsunternehmen
communications - Partie 7: Modèles d'objets de données - Daten- und Kommunikationssicherheit -
pour la gestion des réseaux et systèmes (NSM) Teil 7: Netzwerk und System-Management (NSM) Daten-
(IEC 62351-7:2017) Objekt-Modelle
(IEC 62351-7:2017)
This European Standard was approved by CENELEC on 2017-08-22. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 62351-7:2017 E
European foreword
The text of document 57/1857/FDIS, future edition 1 of IEC 62351-7, prepared by IEC/TC 57 "Power
systems management and associated information exchange" was submitted to the IEC-CENELEC
parallel vote and approved by CENELEC as EN 62351-7:2017.

The following dates are fixed:
(dop) 2018-06-15
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-12-15
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

This document has been prepared under a mandate given to CENELEC by the European Commission
and the European Free Trade Association.
Endorsement notice
The text of the International Standard IEC 62351-7:2017 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:

IEC 61850-7-2 NOTE Harmonized as EN 61850-7-2.
IEC 61850-7-4 NOTE Harmonized as EN 61850-7-4.
IEC 61850-8-1 NOTE Harmonized as EN 61850-8-1.
IEC 61850-9-2 NOTE Harmonized as EN 61850-9-2.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year

IEC/TS 62351-1 -  Power systems management and - -
associated information exchange - Data
and communications security -
Part 1: Communication network and
system security - Introduction to security
issues
IEC/TS 62351-2 -  Power systems management and - -
associated information exchange - Data
and communications security -
Part 2: Glossary of terms
IEC 62351-3 -  Power systems management and EN 62351-3 -
associated information exchange - Data
and communications security -
Part 3: Communication network and
system security - Profiles including TCP/IP
1 2
IEC 62351-4 -  Power systems management and prEN 62351-4 -
associated information exchange -
Data and communications security -
Part 4: Profiles including MMS
IEC/TS 62351-5 -  Power systems management and - -
associated information exchange - Data
and communications security -
Part 5: Security for IEC 60870-5 and
derivatives
IEC/TS 62351-8 -  Power systems management and - -
associated information exchange - Data
and communications security -
Part 8: Role-based access control
IEC 62351-9 -  Power systems management and EN 62351-9 -
associated information exchange - Data
and communications security -
Part 9: Cyber security key management for
power system equipment
Under preparation. Stage at the time of publication: IEC CDV 62351-4:2017.
Under preparation. Stage at the time of publication: prEN 62351-4:2017.
Publication Year Title EN/HD Year

IEEE 754 2008 IEEE Standard for Binary Floating-Point - -
Arithmetic
IETF RFC 2578 1999 Structure of Management Information - -
Version 2 (SMIv2), April 1999,
http://tools.ietf.org/html/rfc2578
IETF RFC 3410 2002 Introduction and Applicability Statements - -
for Internet Standard Management
Framework, December 2002,
http://tools.ietf.org/rfc/rfc3410
IETF RFC 3414 2002 User-based Security Model (USM) for - -
version 3 of the Simple Network
Management Protocol (SNMPv3),
December 2002,
http://tools.ietf.org/rfc/rfc3414
IETF RFC 3826 2004 The Advanced Encryption Standard (AES) - -
Cipher Algorithm in the SNMP User-based
Security Model, June 2004, http://www.rfc-
editor.org/rfc/rfc3826
IETF RFC 4022 2005 Management Information Base for the - -
Transmission Control Protocol (TCP),
March 2005,
http://tools.ietf.org/html/rfc4022
IETF RFC 4113 2005 Management Information Base for the User - -
Datagram Protocol (UDP), June 2005,
http://tools.ietf.org/html/rfc4113
IETF RFC 4292 2006 IP Forwarding Table MIB, April 2006, - -
http://www.rfc-editor.org/rfc/rfc4292
IETF RFC 4293 2006 Management Information Base for the - -
Internet Protocol (IP), April 2006,
http://tools.ietf.org/rfc/rfc4293
IETF RFC 4898 2007 TCP Extended Statistics MIB, May 2007, - -
http://tools.ietf.org/rfc/rfc4898
IETF RFC 5132 2007 IP Multicast MIB, December 2007, - -
http://tools.ietf.org/rfc/rfc5132
IETF RFC 5905 2010 Network Time Protocol Version 4: Protocol - -
and Algorithms Specification, June 2010,
http://tools.ietf.org/rfc/rfc5905
IETF RFC 5590 2009 Transport Subsystem for the Simple - -
Network Management Protocol (SNMP),
June 2009, http://tools.ietf.org/rfc/rfc5590
IETF RFC 5591 2009 Transport Security Model for the Simple - -
Network Management Protocol (SNMP),
June 2009, http://tools.ietf.org/rfc/rfc5591
IETF RFC 5592 2009 Secure Shell Transport Model for the - -
Simple Network Management Protocol
(SNMP), June 2009, http://www.rfc-
editor.org/rfc/rfc5592
Publication Year Title EN/HD Year

IETF RFC 5953 2010 Transport Layer Security (TLS) Transport - -
Model for the Simple Network
Management Protocol (SNMP), August
2010, http://www.rfc-editor.org/rfc/rfc5953
IETF RFC 6347 2012 Datagram Transport Layer Security - -
Version 1.2, January 2012,
http://tools.ietf.org/rfc/rfc6347
IETF RFC 6353 2011 Transport Layer Security (TLS) Transport - -
Model for the Simple Network
Management Protocol (SNMP), July 2011,
http://tools.ietf.org/rfc/rfc6353
IETF RFC 7860 2016 HMAC-SHA-2, Authentication Protocols in - -
User-Based Security Model (USM) for
SNMPv3, April 2016,
http://tools.ietf.org/rfc/rfc7860

IEC 62351-7 ®
Edition 1.0 2017-07
INTERNATIONAL
STANDARD
colour
inside
Power systems management and associated information exchange – Data and

communications security –
Part 7: Network and System Management (NSM) data object models

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.200 ISBN 978-2-8322-4442-5

– 2 – IEC 62351-7:2017 © IEC 2017
CONTENTS
FOREWORD . 8
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 12
4 Abbreviated terms and acronyms . 13
5 Overview of Network and System Management (NSM) . 14
5.1 Objectives . 14
5.2 NSM concepts. 15
5.2.1 Simple Network Management Protocol (SNMP) . 15
5.2.2 ISO NSM categories . 15
5.2.3 NSM “data objects” for power system operations . 16
5.2.4 Other NSM protocols . 16
5.3 Communication network management . 16
5.3.1 Network configuration . 16
5.3.2 Network backup . 17
5.3.3 Communications failures and degradation . 17
5.4 Communication protocols . 18
5.5 End systems management . 18
5.6 Intrusion detection systems (IDS) . 19
5.6.1 IDS guidelines . 19
5.6.2 IDS: Passive observation techniques . 20
5.6.3 IDS: Active security monitoring architecture with NSM data objects . 20
5.7 End-to-end security . 21
5.7.1 End-to-end security concepts. 21
5.7.2 Role of NSM in end-to-end security . 22
5.8 NSM requirements: detection functions . 24
5.8.1 Detecting unauthorized access . 24
5.8.2 Detecting resource exhaustion as a denial of service (DoS) attack . 24
5.8.3 Detecting invalid buffer access DoS attacks . 25
5.8.4 Detecting tampered/malformed PDUs . 25
5.8.5 Detecting physical access disruption . 25
5.8.6 Detecting invalid network access . 25
5.8.7 Detecting coordinated attacks . 26
5.9 Abstract object and agent UML descriptions. 26
5.9.1 Purpose of UML . 26
5.9.2 Abstract types and base types . 27
5.9.3 Enumerated Types. 28
5.9.4 Abstract agents . 28
5.9.5 Unsolicited Event Notification . 31
5.9.6 UML Model extension . 31
5.10 Abstract Object UML translation to SNMP . 31
5.10.1 Simple Network Management Protocol (SNMP) . 31
5.10.2 Management information bases (MIBs) . 32
5.11 SNMP mapping of UML model Objects . 33
5.12 SNMP Security. 34
6 Abstract objects . 36

IEC 62351-7:2017 © IEC 2017 – 3 –
6.1 General . 36
6.2 Package Abstract Types . 37
6.2.1 General . 37
6.2.2 BooleanValue . 37
6.2.3 BooleanValueTs . 37
6.2.4 CounterTs. 37
6.2.5 CntRs . 38
6.2.6 Floating . 38
6.2.7 FloatingTs . 38
6.2.8 EntityIndex . 39
6.2.9 Integer . 39
6.2.10 IntegerTs . 39
6.2.11 InetAddress . 40
6.2.12 InetAddressType . 40
6.2.13 MacAddress . 40
6.2.14 Selector . 40
6.2.15 Timestamp . 41
6.2.16 CharString . 41
6.2.17 CharStringTs . 41
6.2.18 AbstractBaseType root class . 41
6.2.19 AbstractAgent root class . 42
6.3 Package EnumeratedTypes . 42
6.3.1 General . 42
6.3.2 AppDatStKind enumeration . 42
6.3.3 PhyHealthKind enumeration. 42
6.3.4 ExtKind enumeration . 42
6.3.5 IntKind enumeration. 43
6.3.6 LnkKind enumeration . 43
6.3.7 PSPAccKind enumeration . 43
6.3.8 ProtIdKind enumeration . 43
6.3.9 EventKind enumeration . 44
6.3.10 TimSyncIssueKind enumeration . 44
6.3.11 SecurityProfileKind enumeration . 45
6.3.12 TimSyncSrcKind enumeration . 45
6.3.13 AppDatStType . 45
6.3.14 PhyHealthType . 46
6.3.15 ExtType . 46
6.3.16 IntType . 46
6.3.17 EventType . 46
6.3.18 PSPAccType . 47
6.3.19 ProtIdType . 47
6.3.20 TimSyncIssueType . 47
6.3.21 SecurityProfileType . 47
6.3.22 TimSyncSrcType . 48
6.3.23 LnkType . 48
7 Agents . 48
7.1 Package Overview . 48
7.2 Package Environmental Agent . 50
7.2.1 General . 50

– 4 – IEC 62351-7:2017 © IEC 2017
7.2.2 Environmental . 51
7.2.3 PSUPEntry . 51
7.2.4 Notification . 52
7.2.5 SecurityNotification . 52
7.3 Package IED Agent . 53
7.3.1 General . 53
7.3.2 IED . 54
7.3.3 CPUEntry . 55
7.3.4 EXTEntry . 56
7.3.5 STOREEntry . 56
7.3.6 Notification . 57
7.3.7 SecurityNotification . 57
7.4 Package Application Protocols Agents . 57
7.4.1 General . 57
7.4.2 Package Common objects . 58
7.4.3 Package IEEE 1815 and IEC 60870-5 Agent. 59
7.4.4 Package IEC61850 Agent . 68
7.5 Package Interfaces Agent . 87
7.5.1 General . 87
7.5.2 Interface . 88
7.5.3 Interfaces . 88
7.5.4 ETHEntry . 90
7.5.5 KEYEntry . 90
7.5.6 SEREntry. 91
7.5.7 ALGEntry . 91
7.5.8 USBEntry. 92
7.5.9 Notification . 92
7.6 Package Clocks Agent . 93
7.6.1 General . 93
7.6.2 Clock . 93
7.6.3 ClockEntry . 94
7.6.4 SecurityNotification . 95
7.7 Network and Transport Agents . 95
7.7.1 TCP . 95
7.7.2 User Datagram Protocol (UDP) . 95
7.7.3 IP . 95
8 SNMP security . 96
9 Secured time synchronization . 96
Annex A (normative) SNMP MIB Mapping . 97
Annex B (informative) Mapping of relevant IEC 61850 Objects . 229
Bibliography . 230

Figure 1 – Example of a power system SCADA architecture extended with NSM Data
Objects . 15
Figure 2 – IDS Information exchange between applications: generic communication
topology . 19
Figure 3 – Active security monitoring architecture with NSM data objects . 21
Figure 4 – Comparison of NSM data objects with IEC 61850 objects . 23

IEC 62351-7:2017 © IEC 2017 – 5 –
Figure 5 – Management of both the power system infrastructure and the information
infrastructure . 23
Figure 6 – Abstract types . 27
Figure 7 – Enumerated types . 28
Figure 8 – Subagents . 29
Figure 9 – Environmental agent . 30
Figure 10 – Model stereotypes . 30
Figure 11 – Object identifier structure . 32
Figure 12 – SNMP table . 34
Figure 13 – SNMP RFCs map and security . 35
Figure 14 – SNMP Entity . 36
Figure 15 – Class diagram Overview::Part7 Classes Overview . 49
Figure 16 – Class diagram Environmental Agent::Environmental . 50
Figure 17 – Class diagram IED Agent::IED . 53
Figure 18 – Class diagram Common objects::Application Protocol common objects . 58
Figure 19 – Class diagram IEEE 1815 and IEC 60870-5 Agent::IEEE 1815 and
IEC 60870 Agent Relationships . 60
Figure 20 – Class diagram ACSI::ACSI . 69
Figure 21 – Class diagram MMS::MMS . 71
Figure 22 – Class diagram SV and GSE common objects::SV and GSE common
objects . 76
Figure 23 – Class diagram SV::SV . 78
Figure 24 – Class diagram GSE::GSE . 82
Figure 25 – Class diagram Interfaces Agent::Interfaces . 87
Figure 26 – Class diagram Clocks Agent::Clocks Agent . 93

Table 1 – Attributes of Abstract Types::BooleanValue . 37
Table 2 – Attributes of Abstract Types::BooleanValueTs . 37
Table 3 – Attributes of Abstract Types::CounterTs . 38
Table 4 – Attributes of Abstract Types::CntRs . 38
Table 5 – Attributes of Abstract Types::Floating . 38
Table 6 – Attributes of Abstract Types::FloatingTs . 39
Table 7 – Attributes of Abstract Types::EntityIndex . 39
Table 8 – Attributes of Abstract Types::Integer . 39
Table 9 – Attributes of Abstract Types::IntegerTs . 39
Table 10 – Attributes of Abstract Types::InetAddress . 40
Table 11 – Attributes of Abstract Types::InetAddressType . 40
Table 12 – Attributes of Abstract Types::MacAddress . 40
Table 13 – Attributes of Abstract Types::Selector . 41
Table 14 – Attributes of Abstract Types::Timestamp . 41
Table 15 – Attributes of Abstract Types::CharString . 41
Table 16 – Attributes of Abstract Types::CharStringTs . 41
Table 17 – Literals of EnumeratedTypes::AppDatStKind . 42
Table 18 – Literals of EnumeratedTypes::PhyHealthKind . 42

– 6 – IEC 62351-7:2017 © IEC 2017
Table 19 – Literals of EnumeratedTypes::ExtKind . 43
Table 20 – Literals of EnumeratedTypes::IntKind . 43
Table 21 – Literals of EnumeratedTypes::LnkKind . 43
Table 22 – Literals of EnumeratedTypes::PSPAccKind . 43
Table 23 – Literals of EnumeratedTypes::ProtIdKind . 44
Table 24 – Literals of EnumeratedTypes::EventKind . 44
Table 25 – Literals of EnumeratedTypes::TimSyncIssueKind . 44
Table 26 – Literals of EnumeratedTypes::SecurityProfileKind . 45
Table 27 – Literals of EnumeratedTypes::TimSyncSrcKind . 45
Table 28 – Attributes of EnumeratedTypes::AppDatStType . 46
Table 29 – Attributes of EnumeratedTypes::PhyHealthType . 46
Table 30 – Attributes of EnumeratedTypes::ExtType . 46
Table 31 – Attributes of EnumeratedTypes::IntType . 46
Table 32 – Attributes of EnumeratedTypes::EventType . 47
Table 33 – Attributes of EnumeratedTypes::PSPAccType . 47
Table 34 – Attributes of EnumeratedTypes::ProtIdType . 47
Table 35 – Attributes of EnumeratedTypes::TimSyncIssueType . 47
Table 36 – Attributes of EnumeratedTypes::SecurityProfileType . 48
Table 37 – Attributes of EnumeratedTypes::TimSyncSrcType . 48
Table 38 – Attributes of EnumeratedTypes::LnkType . 48
Table 39 – Attributes of Environmental Agent::Environmental . 51
Table 40 – Attributes of Environmental Agent::PSUPEntry . 51
Table 41 – Attributes of Environmental Agent::Notification . 52
Table 42 – Attributes of Environmental Agent::SecurityNotification . 52
Table 43 – Attributes of IED Agent::IED . 54
Table 44 – Attributes of IED Agent::CPUEntry. 55
Table 45 – Attributes of IED Agent::EXTEntry . 56
Table 46 – Attributes of IED Agent::STOREEntry . 56
Table 47 – Attributes of IED Agent::Notification . 57
Table 48 – Attributes of IED Agent::SecurityNotification . 57
Table 49 – Attributes of Common objects::CommonProtocolInfo . 58
Table 50 – Attributes of IEEE 1815 and IEC 60870-5
Agent::60870andDNPProtocolInfo . 61
Table 51 – Attributes of IEEE 1815 and IEC 60870-5 Agent::Association . 62
Table 52 – Attributes of IEEE 1815 and IEC 60870-5 Agent::Summary . 64
Table 53 – Attributes of IEEE 1815 and IEC 60870-5
Agent::60870andDNPSecurityNotification . 65
Table 54 – Attributes of IEEE 1815 and IEC 60870-5 Agent::60870andDNPNotification . 65
Table 55 – Attributes of IEEE 1815 and IEC 60870-5 Agent::MasterAssociation . 66
Table 56 – Attributes of IEEE 1815 and IEC 60870-5 Agent::OutstationAssociation . 67
Table 57 – Attributes of ACSI::ACSISummary . 70
Table 58 – Attributes of MMS::MMSProtocolInfo . 72
Table 59 – Attributes of MMS::MMSProvider . 73
Table 60 – Attributes of MMS::MMSAssociation . 74

IEC 62351-7:2017 © IEC 2017 – 7 –
Table 61 – Attributes of MMS::MMSSecurityNotification . 75
Table 62 – Attributes of MMS::MMSNotification . 75
Table 63 – Attributes of SV and GSE common objects::GSEandSVCommon . 76
Table 64 – Attributes of SV and GSE common
objects::GSEandSVPublisherAssociation . 77
Table 65 – Attributes of SV and GSE common
objects::GSEandSVSubscriberAssociation . 77
Table 66 – Attributes of SV::SVProvider. 79
Table 67 – Attributes of SV::SVPublisherAssociationIP . 79
Table 68 – Attributes of SV::SVPublisherAssociationL2 . 80
Table 69 – Attributes of SV::SVSubcriberAssociationIP. 80
Table 70 – Attributes of SV::SVSubcriberAssociationL2 . 81
Table 71 – Attributes of SV::SVNotification . 81
Table 72 – Attributes of GSE::GSESubscriberAssociation . 83
Table 73 – Attributes of GSE::GSEProvider . 83
Table 74 – Attributes of GSE::GSEPublisherAssociationIP . 84
Table 75 – Attributes of GSE::GSEPublisherAssociationL2 . 84
Table 76 – Attributes of GSE::GSESubcriberAssociationIP . 85
Table 77 – Attributes of GSE::GSESubscriberAssociationL2 . 85
Table 78 – Attributes of GSE::GSENotification . 86
Table 79 – Attributes of Interfaces Agent::Interface. 88
Table 80 – Attributes of Interfaces Agent::Interfaces . 89
Table 81 – Attributes of Interfaces Agent::ETHEntry . 90
Table 82 – Attributes of Interfaces Agent::KEYEntry . 90
Table 83 – Attributes of Interfaces Agent::SEREntry . 91
Table 84 – Attributes of Interfaces Agent::ALGEntry . 91
Table 85 – Attributes of Interfaces Agent::USBEntry . 92
Table 86 – Attributes of Interfaces Agent::Notification . 92
Table 87 – Attributes of Clocks Agent::Clock . 93
Table 88 – Attributes of Clocks Agent::ClockEntry . 94
Table 89 – Attributes of Clocks Agent::SecurityNotification . 95
Table B.1 – IEC 61850-7-4 objects mapping . 229

– 8 – IEC 62351-7:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
POWER SYSTEMS MANAGEMENT AND
ASSOCIATED INFORMATION EXCHANGE –
DATA AND COMMUNICATIONS SECURITY –

Part 7: Network and System Management (NSM) data object models

FOREWORD
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