IEC 61588:2004

Precision clock synchronization protocol for networked measurement and control systems

defines a protocol enabling precise synchronization of clocks in measurement and control systems implemented with technologies such as network communication, local computing, and distributed objects. The protocol will be applicable to systems communicating by local area networks supporting multicast messaging including, but not limited to, Ethernet. This standard is published under the double logo IEC/IEEE.

General Information

• Status: Published
• Publication Date: 15-Sep-2004
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.110 - Networking
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: SC 65C - Industrial networks
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 27-Feb-2009

Relations

• Revised: IEC 61588:2009 - Precision clock synchronization protocol for networked measurement and control systems
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 61588
First edition
2004-09
™
IEEE 1588
Precision clock synchronization protocol
for networked measurement
and control systems
Reference number
IEC 61588(E):2004
IEEE Std. 1588(E):2002
Publication numbering
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INTERNATIONAL IEC
STANDARD 61588
First edition
2004-09
™
IEEE 1588
Precision clock synchronization protocol
for networked measurement
and control systems
Copyright © IEEE 2004 ⎯ All rights reserved
IEEE is a registered trademark in the U.S. Patent & Trademark Office, owned by the Institute of Electrical and Electronics Engineers, Inc.
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
The Institute of Electrical and Electronics Engineers, Inc, 3 Park Avenue, New York, NY 10016-5997, USA
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.standards.ieee.org
Commission Electrotechnique Internationale
International Electrotechnical Commission
Международная Электротехническая Комиссия

– 2 –
IEEE 1588-2002(E)
CONTENTS
Foreword. 4

IEEE introduction. 7

1. Overview. 8

1.1 Scope. 9

1.2 Purpose. 9

2. References. 9
3. Definitions.10
4. Conventions .12
4.1 Descriptive syntax.12
4.2 Word usage .12
4.3 Behavioral specification notation .13
5. Datatypes in a PTP system.15
5.1 Primitive datatypes.15
5.2 Derived datatypes.16
6. PTP Clock synchronization model. 17
6.1 Overview. 17
6.2 PTP systems. 21
7. PTP protocol specification. 33
7.1 Protocol model of a clock . 33
7.2 Protocol model of a subdomain of PTP clocks. 35
7.3 State behavior of clocks. 38
7.4 Clock data set. 42
7.5 Messaging and internal event behavior of clocks. 54
7.6 Best master clock algorithm. 71

7.7 Clock variance computation . 83
7.8 Local clock synchronization . 86
7.9 Values for system and clock constants. . 89
7.10 Physical requirements for PTP implementations. 91
7.11 PTP timing and event ordering constraints. 91
7.12 Management message semantics . 95
8. PTP inter-clock message formats. 95
8.1 Inter-clock messages.102
8.2 PTP message header specification.102
8.3 Sync and Delay_Req messages.105
8.4 Follow_Up messages . 109
8.5 Delay_Resp messages. 110
8.6 Management messages. 111
Published by IEC under licence from IEEE. © 2004 IEEE. All rights reserved.
vi Copyright © 2002 IEEE. All rights reserved.

– 3 –
IEEE 1588-2002(E)
9. Conformance. 120

9.1 Conformance objective . 120

9.2 PTP node conformance requirements . 121

9.3 PTP system conformance requirements. 121

Annex A (informative) Using the PTP protocol. 122

Annex B (informative) Time scales and epochs in PTP . 128

Annex C (normative) subdomain_name to subdomain_address mapping algorithm . 133
Annex D (normative) Ethernet implementation of PTP . 134
Annex E (informative) Bibliography. 151
Annex F (informative) List of Participants . 152

Published by IEC under licence from IEEE. © 2004 IEEE. All rights reserved.
– 4 –
IEEE 1588-2002(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
PRECISION CLOCK SYNCHRONIZATION PROTOCOL

FOR NETWORKED MEASUREMENT AND CONTROL SYSTEMS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization
comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to
promote international co-operation on all questions concerning standardization in the electrical and
electronic fields. To this end and in addition to other activities, IEC publishes International Standards,
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referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National
Committee interested in the subject dealt with may participate in this preparatory work. International,
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International Standard IEC/IEEE 61588 has been processed through subcommittee 65C:
Digital communications, of IEC technical committee 65: Industrial-process measurement
and control.
The text of this standard is based on the following documents:

IEEE Std FDIS Report on voting
1588 (2002) 65C/333/FDIS 65C/340/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The committee has decided that the contents of this publication will remain unchanged until
2007.
Published by IEC under licence from IEEE. © 2004 IEEE. All rights reserved.

Published by IEC under licence from IEEE. © 2004 IEEE. All rights reserved.

– 5 –
IEEE 1588-2002(E)
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