IEC TS 60870-5-7:2025

IEC TS 60870-5-7 ®
Edition 2.0 2025-03
TECHNICAL
SPECIFICATION
Telecontrol equipment and systems –
Part 5-7: Transmission protocols – Security extensions to IEC 60870-5-101 and
IEC 60870-5-104 protocols (applying IEC 62351)

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IEC TS 60870-5-7 ®
Edition 2.0 2025-03
TECHNICAL
SPECIFICATION
Telecontrol equipment and systems –

Part 5-7: Transmission protocols – Security extensions to IEC 60870-5-101 and

IEC 60870-5-104 protocols (applying IEC 62351)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.200  ISBN 978-2-8327-0275-8

– 2 – IEC TS 60870-5-7:2025 © IEC 2025
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms. 8
4 Overview of IEC 60870-5-7 profiles . 9
5 A-Profile: Implementation of IEC 62351-5 . 9
5.1 General . 9
5.2 Selected options . 9
5.2.1 Overview of clause . 9
5.2.2 MAC algorithms . 10
5.2.3 Encryption algorithms . 10
5.3 Implementation of procedures . 10
5.3.1 Overview of clause . 10
5.3.2 Detection of communication failures . 10
5.3.3 Algorithm selection for Update Keys derivation . 10
5.3.4 Session keys – Application and management . 10
5.3.5 Co-existence with non-secure implementations . 13
5.4 Implementation of messages. 13
5.4.1 Overview of clause . 13
5.4.2 Data definitions. 14
5.4.3 Application Service Data Units . 19
6 T-Profile Security: Implementation of IEC 62351-3 . 37
7 Security profiles for IEC 60870-5-101 and IEC 60870-5-104 . 38
7.1 General . 38
7.2 Security profiles for IEC 60870-5-101 . 38
7.3 Security profiles for IEC 60870-5-104 . 38
7.3.1 General. 38
7.3.2 Use with redundant channels . 38
8 Considerations for role-based access control (RBAC) . 39
8.1 General . 39
8.2 Permission definition . 40
8.3 Role-to-permission assignment . 41
9 Protocol Implementation Conformance Statement . 42
9.1 Overview of clause . 42
9.2 Algorithms for digital certificates. 42
9.2.1 Cryptographic curves for key pair generation . 42
9.2.2 Certificate signature algorithms . 42
9.3 MAC algorithms . 43
9.3.1 General. 43
9.3.2 MAC algorithms for serial links . 43
9.3.3 MAC algorithms for TCP/IP links . 43
9.4 Key wrap algorithms . 43
9.5 Data protection algorithms . 43
9.5.1 General. 43

9.5.2 Data protection algorithms for serial links . 43
9.5.3 Data protection algorithms for TCP/IP links . 44
9.6 Configurable parameters . 44
9.7 Configurable statistic thresholds and statistic information object addresses . 45
9.8 Security profile support . 46
Annex A (informative) Implementation of A-Profile security with IEC 60870-5-101 . 47
Annex B (informative) Devices with inaccurate clocks . 49
Bibliography . 50

Figure 1 – IEC 60870-5-7 Profiles . 9
Figure 2 – ASDU segmentation control . 15
Figure 3 – Segmenting extended ASDUs . 16
Figure 4 – Illustration of ASDU segment reception state machine . 19
Figure 5 – Example of a MAC calculation of a Secure Data message . 20
Figure 6 – ASDU: S_AQ_NA_1 Association Request . 21
Figure 7 – Association Request PRI field . 21
Figure 8 – ASDU: S_AP_NA_1 Association Response . 22
Figure 9 – ASDU: S_UH_NA_1 Update Key Change Request. 23
Figure 10 – ASDU: S_UP_NA_1 Update Key Change Response . 24
Figure 11 – ASDU: S_SI_NA_1 Session Initiation Request . 25
Figure 12 – ASDU: S_SQ_NA_1 Session Request . 27
Figure 13 – Session Request PRI field . 28
Figure 14 – ASDU: S_SP_NA_1 Session Response . 29
Figure 15 – ASDU: S_KH_NA_1 Session Key Change Request . 31
Figure 16 – Example of an initial Broadcast Session Key distribution . 33
Figure 17 – Examples of Broadcast Session Key update . 34
Figure 18 – ASDU: S_KP_NA_1 Session Key Change Response. 35
Figure 19 – Example of an AEAD calculation of a Secure Data message . 36
Figure 20 – ASDU: S_SD_NA_1 Secure Data . 37
Figure 21 – RBAC mapped to IEC 60870-5-101/-104. 39
Figure A.1 – Unbalanced transmission system . 47
Figure A.2 – Balanced transmission system . 48

Table 1 – Additional cause of transmission. 14
Table 2 – Additional type identifiers . 14
Table 3 – ASDU segment reception state machine . 18
Table 4 – Session Initiation Request: data Included in MAC calculation (in order) . 27
Table 5 – Session Response: data Included in MAC calculation (in order) . 30
Table 6 – Data Included in WKD for Broadcast Session Key change (in order) . 32
Table 7 – List of pre-defined permissions . 40
Table 8 – List of pre-defined role-to-permission assignments for IEC 60870-5-101/-104
(updated version from IEC 62351-5:2023) . 41
Table 9 – List of the configurable parameters . 44
Table 10 – Security statistic . 45

– 4 – IEC TS 60870-5-7:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TELECONTROL EQUIPMENT AND SYSTEMS –

Part 5-7: Transmission protocols – Security extensions to
IEC 60870-5-101 and IEC 60870-5-104 protocols
(applying IEC 62351)
FOREWORD
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interested IEC Nationa
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