IEC 61588:2021

IEC 61588 ®
Edition 3.0 2021-06
™
IEEE Std 1588
INTERNATIONAL
STANDARD
Precision Clock Synchronization Protocol for Networked Measurement and
Control Systems
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IEC 61588 ®
Edition 3.0 2021-06
IEEE Std 1588™
INTERNATIONAL
STANDARD
Precision Clock Synchronization Protocol for Networked Measurement and

Control Systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.110; 35.240.50 ISBN 978-2-8322-9811-4

IEEE Std 1588™-2019 – i –
Contents
1. Scope . 14
2. Normative references . 15
3. Definitions, acronyms, and abbreviations. 16
3.1 Definitions . 16
3.2 Acronyms and abbreviations . 24
4. Conventions . 26
4.1 Descriptive lexical form syntax . 26
4.2 Word usage . 27
4.3 Behavioral specification notation . 28
5. Data types and on-the-wire formats . 30
5.1 General . 30
5.2 Primitive data type specifications . 30
5.3 Derived data type specifications . 31
5.4 On-the-wire formats . 35
6. Clock synchronization model . 36
6.1 General requirements on implementations . 36
6.2 Principal assumptions about the network and implementation recommendations . 39
6.3 PTP Networks . 39
6.4 PTP message classes . 40
6.5 PTP device types . 41
6.6 Synchronization overview. 53
6.7 PTP communications overview . 65
7. Characterization of PTP entities . 69
7.1 Domains . 69
7.2 Timescales used in PTP . 72
7.3 PTP communications . 74
7.4 PTP communication media . 81
7.5 PTP Ports . 84
7.6 PTP Instance characterization . 89
7.7 PTP timing characterization . 103
8. PTP data sets. 105
8.1 General specifications for data set members . 105
8.2 Data sets for PTP Instances . 113
8.3 Data sets for Transparent Clocks . 141
8.4 commonMeanLinkDelayService data sets . 144
9. PTP for Ordinary Clocks and Boundary Clocks . 144
9.1 General protocol requirements for PTP Ordinary Clocks and Boundary Clocks . 144
9.2 State protocol . 145
9.3 Best master clock algorithms . 154
9.4 Grandmaster PTP Instance timePropertiesDS updates . 164
9.5 PTP message processing semantics . 166
9.6 Changes in the PTP Instance . 182
10. PTP for Transparent Clocks . 182
10.1 Requirements for both end-to-end and peer-to-peer Transparent Clocks . 182
10.2 End-to-end Transparent Clock requirements . 182
10.3 Peer-to-peer Transparent Clock requirements . 191
11. Clock offset, path delay, residence time, and asymmetry corrections . 195

Published by IEC under licence from IEEE. © 2019 IEEE. All rights reserved.

– ii – IEEE Std 1588™-2019
11.1 General specifications . 195
11.2 Computation of in Ordinary Clocks and Boundary Clocks . 196
11.3 Delay request-response mechanism for Ordinary Clocks and Boundary Clocks . 197
11.4 Peer-to-peer delay mechanism . 199
11.5 MDMI interface and Special Ports . 204
12. Synchronization and syntonization of clocks . 214
12.1 Clock adjustments . 214
12.2 Syntonization . 214
12.3 Synchronization . 215
13. PTP message formats . 216
13.1 General. 216
13.2 General PTP message format requirements. 216
13.3 Header. 216
13.4 Suffix . 222
13.5 Announce message . 222
13.6 Sync and Delay_Req messages . 224
13.7 Follow_Up message . 224
13.8 Delay_Resp message . 225
13.9 Pdelay_Req message . 225
13.10 Pdelay_Resp message . 226
13.11 Pdelay_Resp_Follow_Up message . 226
13.12 Signaling message . 227
13.13 PTP management message . 228
14. TLV entity specifications . 228
14.1 General requirements . 228
14.2 Propagation of TLVs through Boundary Clocks . 230
14.3 Vendor and standard organization extension TLVs . 231
14.4 PAD TLV (optional) . 233
15. PTP management messages (optional) . 234
15.1 General. 234
15.2 PTP management mechanism . 234
15.3 Processing of PTP management messages . 234
15.4 PTP management message format .
...