BS EN 62439-3:2012 BSI Standards Publication Industrial communication networks — High availability automation networks Part 3: Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR) NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW raising standards worldwide™ BRITISH STANDARD BS EN 62439-3:2012 National foreword This British Standard is the UK implementation of EN 62439-3:2012 It is identical to IEC 62439-3:2012 It supersedes BS EN 62439-3:2010 which is withdrawn The UK participation in its preparation was entrusted to Technical Committee AMT/7, Industrial communications: process measurement and control, including fieldbus A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © The British Standards Institution 2012 Published by BSI Standards Limited 2012 ISBN 978 580 73809 ICS 25.040.01; 35.040 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 October 2012 Amendments issued since publication Amd No Date Text affected BS EN 62439-3:2012 EUROPEAN STANDARD EN 62439-3 NORME EUROPÉENNE September 2012 EUROPÄISCHE NORM ICS 25.040; 35.040 Supersedes EN 62439-3:2010 English version Industrial communication networks High availability automation networks Part 3: Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR) (IEC 62439-3:2012) Réseaux industriels de communication Réseaux d’automatisme haute disponibilité Partie : Protocole de redondance parallèle (PRP) et redondance transparente de haute disponibilité (HSR) (CEI 62439-3:2012) Industrielle Kommunikationsnetze Hochverfügbare Automatisierungsnetze Teil 3: Parallelredundanz-Protokoll (PRP) und nahtloser Hochverfügbarkeits-Ring (HSR) (IEC 62439-3:2012) This European Standard was approved by CENELEC on 2012-08-09 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels © 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 62439-3:2012 E BS EN 62439-3:2012 EN 62439-3:2012 -2- Foreword The text of document 65C/687/FDIS, future edition of IEC 62439-3, prepared by SC 65C, "Industrial networks", of IEC TC 65, "Industrial-process measurement, control and automation" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 62439-3:2012 The following dates are fixed: • • 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 standards conflicting with the document have to be withdrawn (dop) 2013-05-09 (dow) 2015-08-09 This document supersedes EN 62439-3:2010 EN 62439-3:2012 includes the following significant technical changes with respect to EN 62439-3:2010: – specification of the interconnection of PRP and HSR networks; – introduction of a suffix for PRP frames; – clarification and modification of specifications to ensure interoperability; – slackening of the specifications to allow different implementations; – consideration of clock synchronization according to IEC 61588; – introduction of test modes to simplify testing and maintenance This standard is to be used in conjunction with EN 62439-1:2010 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights Endorsement notice The text of the International Standard IEC 62439-3:2012 was approved by CENELEC as a European Standard without any modification In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 61580 series NOTE Harmonized in EN 61580 series (not modified) BS EN 62439-3:2012 EN 62439-3:2012 -3- Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies Publication Year Title EN/HD Year IEC 60050-191 - International Electrotechnical Vocabulary (IEV) Chapter 191: Dependability and quality of service - - IEC 61588 - Precision clock synchronization protocol for networked measurement and control systems - IEC 62439-1 - Industrial communication networks - High availability automation networks Part 1: General concepts and calculation methods EN 62439-1 - IEC 62439-2 - Industrial communication networks - High availability automation networks Part 2: Media Redundancy Protocol (MRP) EN 62439-2 - IEC 62439-6 - Industrial communication networks - High availability automation networks Part 6: Distributed Redundancy Protocol (DRP) EN 62439-6 - IEC 62439-7 - Industrial communication networks - High availability automation networks Part 7: Ring-based Redundancy Protocol (RRP) EN 62439-7 - ISO/IEC 8802-3 2000 Information technology - Telecommunications and information exchange between systems Local and metropolitan area networks Specific requirements Part 3: Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications - IEEE 802.1D 2004 IEEE Standard for Local and Metropolitan Area Networks - Media Access Control (MAC) Bridges - IEEE 802.1Q 2011 IEEE Standard for Local and Metropolitan Area Networks - Virtual Bridged Local Area Networks - - –2– BS EN 62439-3:2012 62439-3 © IEC:2010(E) CONTENTS INTRODUCTION Scope .8 Normative references .8 Terms, definitions, abbreviations, acronyms, and conventions 3.1 Terms and definitions 3.2 Abbreviations and acronyms 3.3 Conventions Parallel Redundancy Protocol (PRP) 4.1 PRP principle of operation .9 4.1.1 PRP network topology 4.1.2 PRP LANs with linear or bus topology 10 4.1.3 PRP LANs with ring topology 11 4.1.4 DANP node structure 11 4.1.5 PRP attachment of singly attached nodes 12 4.1.6 Compatibility between singly and doubly attached nodes 12 4.1.7 Network management 12 4.1.8 Implication on configuration 13 4.1.9 Transition to non-redundant networks 13 4.1.10 Duplicate handling 14 4.1.11 Configuration check 18 4.1.12 Network supervision 18 4.1.13 Redundancy management interface 19 4.2 PRP protocol specifications 19 4.2.1 Installation, configuration and repair guidelines 19 4.2.2 MAC addresses 20 4.2.3 Multicast MAC addresses 20 4.2.4 IP addresses 20 4.2.5 Nodes 20 4.2.6 Duplicate accept mode 21 4.2.7 Duplicate discard mode 21 4.3 PRP service specification 27 4.3.1 Arguments 27 4.3.2 NodesTable 28 4.3.3 PRP write 29 4.3.4 PRP read 30 High-availability Seamless Redundancy (HSR) 31 5.1 5.2 5.3 HSR objectives 31 HSR principle of operation 31 5.2.1 Basic operation with a ring topology 31 5.2.2 DANH node structure 33 5.2.3 Topology 34 5.2.4 RedBox structure 40 HSR node specifications 42 5.3.1 Host sequence number 42 5.3.2 DANH receiving from its link layer interface 42 BS EN 62439-3:2012 62439-3 © IEC:2010(E) –3– 5.3.3 DANH receiving from an HSR port 42 5.3.4 DANH forwarding rules 43 5.3.5 CoS 44 5.3.6 Clock synchronization 44 5.3.7 Deterministic medium access 44 5.4 HSR RedBox specifications 44 5.4.1 RedBox properties 44 5.4.2 RedBox receiving from interlink 45 5.4.3 RedBox forwarding on the ring 46 5.4.4 RedBox receiving from an HSR port 46 5.4.5 Redbox proxy node table handling 47 5.4.6 RedBox CoS 47 5.4.7 RedBox clock synchonization 47 5.4.8 RedBox medium access 47 5.5 QuadBox specification 47 5.6 Association definition 47 5.7 Frame format for HSR 47 5.7.1 HSR-tagged frame format 47 5.7.2 HSR_Supervision frame 48 5.7.3 Constants 50 Protocol Implementation Conformance Statement (PICS) 51 PRP/HSR Management Information Base (MIB) 51 Bibliography 58 Figure – PRP example of general redundant network 10 Figure – PRP example of redundant network as two LANs (bus topology) 10 Figure – PRP example of redundant ring with SANs and DANPs 11 Figure – PRP with two DANPs communicating 11 Figure – PRP RedBox, transition from single to double LAN 13 Figure – PRP frame extended by an RCT 15 Figure – PRP VLAN-tagged frame extended by an RCT 15 Figure – PRP constructed, padded frame closed by an RCT 16 Figure – PRP drop window on LAN_A 17 Figure 10 – PRP drop window reduction after a discard 17 Figure 11 – PRP frame from LAN_B was not discarded 18 Figure 12 – PRP synchronized LANs 18 Figure 13 – HSR example of ring configuration for multicast traffic 32 Figure 14 – HSR example of ring configuration for unicast traffic 33 Figure 15 –HSR structure of a DANH 34 Figure 16 – HSR example of topology using two independent networks 35 Figure 17 – HSR example of peer coupling of two rings 36 Figure 18 – HSR example of connected rings 37 Figure 19 – HSR example of coupling two redundant PRP LANs to a ring 38 Figure 20 – HSR example of coupling from a ring node to redundant PRP LANs 39 Figure 21 – HSR example of meshed topology 40 Figure 22 – HSR structure of a RedBox 41 –4– BS EN 62439-3:2012 62439-3 © IEC:2010(E) Figure 23 – HSR frame without VLAN tag 48 Figure 24 – HSR frame with VLAN tag 48 Table – PRP_Supervision frame with VLAN tag 25 Table – PRP constants 27 Table – PRP arguments 28 Table – PRP arguments 29 Table – PRP write 29 Table – PRP read 30 Table – HSR_Supervision frame with optional VLAN tag 49 Table – HSR Constants 50 BS EN 62439-3:2012 62439-3 © IEC:2010(E) –7– INTRODUCTION The IEC 62439 series specifies relevant principles for high availability networks that meet the requirements for industrial automation networks In the fault-free state of the network, the protocols of the IEC 62439 series provide ISO/IEC 8802-3 (IEEE 802.3) compatible, reliable data communication, and preserve determinism of real-time data communication In cases of fault, removal, and insertion of a component, they provide deterministic recovery times These protocols retain fully the typical Ethernet communication capabilities as used in the office world, so that the software involved remains applicable The market is in need of several network solutions, each with different performance characteristics and functional capabilities, matching diverse application requirements These solutions support different redundancy topologies and mechanisms which are introduced in IEC 62439-1 and specified in the other Parts of the IEC 62439 series IEC 62439-1 also distinguishes between the different solutions, giving guidance to the user The IEC 62439 series follows the general structure and terms of IEC 61158 series The International Electrotechnical Commission (IEC) draws attention to the fact that it is claimed that compliance with this document may involve the use of a patent concerning detection of redundant frames given in 4.1.10.3, and concerning coupling of PRP and HSR LANs given in 5.4 (patent pending) IEC takes no position concerning the evidence, validity and scope of this patent right The holder of this patent right has assured the IEC that he/she is willing to negotiate licences either free of charge or under reasonable and non-discriminatory terms and conditions with applicants throughout the world In this respect, the statement of the holder of this patent right is registered with IEC Information may be obtained from: ABB Switzerland Ltd Corporate Research Segelhofstr 1K 5405 Baden Switzerland Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights other than those identified above IEC shall not be held responsible for identifying any or all such patent rights ISO (www.iso.org/patents) and IEC (http://www.iec.ch/tctools/patent_decl.htm) maintain online data bases of patents relevant to their standards Users are encouraged to consult the data bases for the most up to date information concerning patents –8– BS EN 62439-3:2012 62439-3 © IEC:2010(E) INDUSTRIAL COMMUNICATION NETWORKS – HIGH AVAILABILITY AUTOMATION NETWORKS – Part 3: Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR) Scope The IEC 62439 series is applicable to high-availability automation networks based on the ISO/IEC 8802-3 (IEEE 802.3) (Ethernet) technology This part of the IEC 62439 series specifies two redundancy protocols based on the duplication of the LAN, resp duplication of the transmitted information, designed to provide seamless recovery in case of single failure of an inter-switch link or switch in the network Normative references The following referenced documents are indispensable for the application 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 IEC 60050-191:1990, International Electrotechnical Vocabulary – Chapter 191: Dependability and quality of service IEC 62439-1:2010, Industrial communication networks – High availability automation networks – Part 1: General concepts and calculation methods ISO/IEC 8802-3:2000, Information technology – Telecommunications and information exchange between systems – Local and metropolitan area networks – Specific requirements – Part 3: Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications IEEE 802.1D:2004, IEEE standard for local Local and metropolitan area networks Media Access Control (MAC) Bridges IEEE 802.1Q, IEEE standards for local and metropolitan area network Virtual bridged local area networks Terms, definitions, abbreviations, acronyms, and conventions 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60050-191, as well as in IEC 62439-1, apply, in addition to the following 3.1.1 extended frame frame that has been extended by a Redundancy Control Trailer 3.1.2 interlink link that connects two network hierarchies – 46 – BS EN 62439-3:2012 62439-3 © IEC:2010(E) Reuse the PRP sequence number and path identifier to build the HSR tag Enqueue the unmodified frame into each HSR port Else (if the frame carries neither a HSR tag nor a PRP RCT) If the source MAC address is not already registered: Create an entry in the proxy node table with a sequence number of 0; Register that source as SAN Else (If the source is already registered) Register the presence of that source; If the RedBox is a destination of the frame: Enqueue to the link layer interface of the RedBox If the frame is to be injected into the ring (RedBox is not sole destination and multicast/VLAN is ok) If this is not the first occurrence of the frame at each HSR port Register the occurrence Discard the frame (already sent over that port) Else (If this is the first occurrence of the frame at each HSR port) Append the HSR tag using the sequence number of that node Increment the sequence number of that source; Enqueue the tagged frame into each HSR port NOTE Reception of an HSR frame over the interlink is considered as a configuration error in PRP connection mode If the RedBox is used as one half of a QuadBox in HSR connection mode, then the interlink will only carry HSR traffic 5.4.3 RedBox forwarding on the ring In addition to the forwarding rules of 5.3.4 , a RedBox shall not forward in the ring a unicast frame that is intended for one of the nodes that are registered in the proxy node table This condition is enabled by default and can be disabled for debugging purposes 5.4.4 RedBox receiving from an HSR port A RedBox that receives a valid frame over one HSR port shall: If this frame is not HSR-tagged: Register the source as a non-HSR source; Enqueue the frame for passing to the link layer interface of the RedBox; (do not forward it) Else (frame is HSR-tagged): If this is the first occurrence of the frame in direction of the second HSR port Register the occurrence of the frame; Enqueue the frame to the second port; Else (If this is not the first occurrence of the frame in direction of the second HSR port) Register the occurrence of the frame; Do not enqueue the unchanged frame to the second HSR port; If this is the first occurrence of the frame in direction of the interlink: Register the occurrence of the frame; If the RedBox is in SAN mode: Remove the HSR tag; BS EN 62439-3:2012 62439-3 © IEC:2010(E) – 47 – Else if the RedBox is in PRP mode: Remove the HSR tag and append the PRP RCT “A” or “B” reusing the HSR sequence number Else (if the RedBox is in HSR mode) Do not modify the frame Enqueue frame for passing to the interlink Else (If this is not the first occurrence of the frame in direction of the interlink): Register the occurrence; Discard the frame; NOTE A RedBox does not check if the frame was sent by one of the nodes for which it is a proxy since it cannot distinguish if the frame could have been sent by a redundant RedBox 5.4.5 Redbox proxy node table handling A RedBox shall hold a proxy node table containing an entry for each represented association, which shall support at least ProxyTableMaxEntries entries A RedBox shall purge the entry of a node in the Proxy Node Table with a configurable timeout (default of ProxyTableForgetTime) for non-receiving frames of this node NOTE 5.4.6 The actual size of the proxy node table is indicated in the PICS RedBox CoS Same as 5.3.5, except that RedBox is expected to support more VLANs and more complex and comprehensive options for engineering traffic flow in the network on higher protocol layers, e.g multicast filtering rules, than a simple node 5.4.7 RedBox clock synchonization Same as 5.3.6 5.4.8 RedBox medium access Same as 5.3.7., except that the RedBox must be able to aggregate several nodes for which it acts as a proxy 5.5 QuadBox specification A Quadbox shall operate conceptually as two RedBoxes in HSR-HSR mode, back-to-back 5.6 Association definition For the purpose of duplicate discard, a frame shall be identified by: – its source MAC address; – a sequence number; – the VLAN identifier NOTE It is possible to use other fields of the frame such as the checksum to aid in duplicate detection 5.7 Frame format for HSR 5.7.1 HSR-tagged frame format Frames to be treated HSR are identified uniquely by their source MAC address, destination MAC address and HSR tag BS EN 62439-3:2012 62439-3 © IEC:2010(E) – 48 – If the frame carries a VLAN tag according to IEEE 802.1Q, it shall be inserted before the HSR tag The HSR tag is announced by the dedicated EtherType = 0x88FB, which is the same as the EtherType used in 4.2.7.6 The most significant bits of the next 16 bits distinguish a HSR management frame from a PRP management frame or a HSR payload a) 4-bit path identifier b) 12 bit frame size (LSDU_size) or version if smaller than 64 preamble octet position destination source 0x88FB 12 path c) 16-bit sequence number (SequenceNr) LSDU sequence _size Nr 16 14 LT payload LSDU FCS 18 HSR tag time IEC original LPDU 378/10 Figure 23 – HSR frame without VLAN tag The definition of the 4-bit path field is: • 0000: PRP management (supervision frames), • 0001 – 1001: ring identifier (regular HSR frames), • 1010 – 1011: frames from PRP network (“A” and “B”), • 1011 – 1100: reserved, • 1111: HSR management (supervision frames), • other: reserved octet position destination source 8100 VLAN 12 88FB 16 VLAN tag path preamble prio The same frame with a VLAN tag is shown in Figure 24 18 LSDU sequence _size Nr 20 HSR tag LT payload LSDU FCS 22 time original LPDU IEC 379/10 Figure 24 – HSR frame with VLAN tag NOTE The frames used within the ring include the HSR tag at the beginning of the frame to allow early identification of frames for cut-through operation NOTE The LSDU_Size has the same definition as in PRP; it does not include the MAC header and VLAN tag, but includes the HSR tag itself and the original LPDU The VLAN tag can be removed by intermediate switches NOTE The reason for inserting the HSR tag after the VLAN tag is to provide faster MAC address lookup in case IVL (Independent VLAN learning as defined in IEEE 802.1Q) is used 5.7.2 5.7.2.1 HSR_Supervision frame Sending Each DANH shall multicast a HSR_Supervision frame over its ports with the format specified in Table After initialization, the node shall send three HSR_Supervision frames with HSR_TLV.Type = 22 in a row at an interval of AnnounceInterval to allow other devices to BS EN 62439-3:2012 62439-3 © IEC:2010(E) – 49 – clear their duplicate records, afterwards it shall send a HSR_Supervision frame with HSR_TLV.Type = 23 every LifeCheckInterval as specified in Table A RedBox in PRP mode shall be considered as a DANP when seen over its PRP interlink and broadcast the PRP_Supervision frame on its PRP interlink Table – HSR_Supervision frame with optional VLAN tag msb U/L I/G 10 11 12 13 14 HSR_DestinationAddress = multicast (01-15-4E-00-01-XX) lsb msb U/L HSR_SourceAddress (MAC address of the adapter) 10 lsb 12 ptid ( = 0x8100 for VLAN) 14 prio cti vlan_identifier 16 pt ( = 0x88FB for HSR) 18 path HSR_Ver (< 64) 20 sequenceNumber 22 HSR_TLV.Type = 22 or 23 24 msb 26 HSR_TLV.Length = 12 U/L MacAddressA (MAC address A of the DANH) 28 lsb 30 32 unused 34 36 HSR_TLV2.Type = 30 or 31 38 msb 40 HSR_TLV2.Length = U/L RedBoxMacAddress 42 lsb Padding to 64 octets (no VLAN) or to 68 octets (VLAN) 64 FCS 66 NOTE The format of the frame is nearly identical to that of the PRP supervision frames 5.7.2.2 HSR_Supervision frame contents HSR_DestinationAddress Reserved multicast address 01-15-4E-00-01-XX shall be used for this protocol By default XX is “00”, but if conflicts arise, XX can be configured to take any value between 0x00 and 0xFF HSR_SourceAddress MAC address of the sending adapter HSR_Ver Indicates the protocol version, set to “0” (zero) for this version of HSR Implementation of version X of the protocol shall interpret version >X as if they were version X, ignoring any parameters and/or flags added by the more recent version, and 15 – 50 – BS EN 62439-3:2012 62439-3 © IEC:2010(E) interpret version dropWindowMax) { if expectedSeq(otherLAN) == startSeq(thisLAN) { // register sequence error cntErrStall(otherLAN) = cntErrStall(otherLAN) + } BS EN 62439-3:2012 62439-3 © IEC:2010(E) – 57 – startSeq(thisLAN) = (expectedSeq(thisLAN) + TwoPi – dropWindowMax) Mod TwoPi // adjust window } // slide window } // correct sequence startSeq(otherLAN) = expectedSeq(otherLAN) // disable the other LAN expectedSeq(thisLAN) = (currentSeq(thisLAN) + 1) Mod TwoPi // new expected sequence nr Forward_To_UpperLayer (thisLAN) } A.3.5 Timeout process // execute at CheckLiveTime interval for each source in sourcelist if (source.timeLastSeenA – currentTime) then source.missingErrorLANB++ // just register the error, no impact on algorithm endif – 58 – BS EN 62439-3:2012 62439-3 © IEC:2010(E) Bibliography IEC 61588, Precision clock synchronization protocol for networked measurement and control systems (IEEE 1588) IEC 62439 (all parts), Industrial communication networks – High availability automation networks IEC 62439-2, Industrial communication networks – High availability automation networks – Part 2: Media Redundancy Protocol (MRP) IEC 62439-4, Industrial communication networks – High availability automation networks – Part 4: Cross-network Redundancy Protocol (CRP) IEC 62439-5, Industrial communication networks – High availability automation networks – Part 5: Beacon Redundancy Protocol (BRP) IEC 62439-6, Industrial communication networks – High availability automation networks – Part 6: Distributed Redundancy Protocol (DRP) ISO/IEC 8802-2, Information technology – Telecommunications and information exchange between systems – Local and metropolitan area networks – Specific requirements – Part 2: Logical link control (IEEE 802.2) ISO/IEC 10164-1, Information technology – Open Systems Interconnection – Systems Management : Object Management Function _ This page deliberately left blank British Standards Institution (BSI) BSI is the independent national body responsible for preparing British Standards and other standards-related publications, information and services It presents the UK view on standards in Europe and at the international level BSI is incorporated by Royal Charter British Standards and other standardisation products are published by BSI Standards Limited 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