IEC 61588:2009

IEC 61588
Edition 2.0 2009-02
™
IEEE 1588
INTERNATIONAL
STANDARD
Precision clock synchronization protocol for networked measurement and
control systems
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IEC 61588
Edition 2.0 2009-02
IEEE 1588™
INTERNATIONAL
STANDARD
Precision clock synchronization protocol for networked measurement and

control systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XH
ICS 25.040.40; 35.110; 35.240.50 ISBN 978-2-88910-546-5

– i – IEC 61588:2009(E)
IEEE 1588-2008(E)
CONTENTS
Foreword.xi
IEEE introduction. xiv
1. Overview . 1
1.1 Scope . 1
1.2 Purpose . 2
1.3 Layout of the document. 2
2. Normative references. 3
3. Definitions, acronyms, and abbreviations . 4
3.1 Definitions . 4
3.2 Acronyms and abbreviations . 7
4. Conventions. 8
4.1 Descriptive lexical form syntax . 8
4.2 Word usage. 9
4.3 Behavioral specification notation . 10
5. Data types and on-the-wire formats in a PTP system. 11
5.1 General . 11
5.2 Primitive data type specifications. 11
5.3 Derived data type specifications. 12
5.4 On-the-wire formats . 15
6. Clock synchronization model . 16
6.1 General . 16
6.2 Principle assumptions about the network and implementation recommendations. 16
6.3 PTP systems. 17
6.4 PTP message classes. 17
6.5 PTP device types . 18
6.6 Synchronization overview . 29
6.7 PTP communications overview . 37
7. Characterization of PTP entities . 41
7.1 Domains. 41
7.2 PTP timescale . 41
7.3 PTP communications. 42
7.4 PTP communication media. 46
7.5 PTP ports . 47
7.6 PTP device characterization . 53
7.7 PTP timing characterization . 61
8. PTP data sets . 63
8.1 General specifications for data set members . 63
8.2 Data sets for ordinary and boundary clocks. 65
8.3 Data sets for transparent clocks . 74
9. PTP for ordinary and boundary clocks . 76
9.1 General protocol requirements for PTP ordinary and boundary clocks. 76
9.2 State protocol. 76
9.3 Best master clock algorithm . 83
9.4 Grandmaster clocks . 92
9.5 Message processing semantics . 93
9.6 Changes in the local clock . 107
10. PTP for transparent clocks. 107
10.1 General requirements for both end-to-end and peer-to-peer transparent clocks . 107
10.2 End-to-end transparent clock requirements . 108
Published by IEC under licence from IEEE. © 2008 IEEE. All rights reserved.

IEEE 1588-2008(E)
10.3 Peer-to-peer transparent clock requirements. 108
11. Clock offset, path delay, residence time, and asymmetry corrections. 108
11.1 General specifications. 108
11.2 Computation of clock offset in ordinary and boundary clocks. 109
11.3 Delay request-response mechanism. 110
11.4 Peer delay mechanism . 112
11.5 Transparent clock residence time correction for PTP version 2 events . 117
11.6 Asymmetry correction for PTP version 2 event messages. 120
12. Synchronization and syntonization of clocks . 122
12.1 Syntonization. 122
12.2 Synchronization. 123
13. PTP message formats . 124
13.1 General . 124
13.2 General message format requirements. 124
13.3 Header. 124
13.4 Suffix . 128
13.5 Announce message . 128
13.6 Sync and Delay_Req messages. 130
13.7 Follow_Up message . 130
13.8 Delay_Resp message . 130
13.9 Pdelay_Req message . 131
13.10 Pdelay_Resp message. 131
13.11 Pdelay_Resp_Follow_Up message. 132
13.12 Signaling message . 132
13.13 Management message. 133
14. TLV entity specifications . 133
14.1 General requirements. 133
14.2 Experimental TLVs . 134
14.3 Vendor and standard organization extension TLVs. 135
15. Management .
...