ISO/IEC 24771:2014

Information technology - Telecommunications and information exchange between systems - MAC/PHY standard for ad hoc wireless network to support QoS in an industrial work environment

ISO/IEC 24771:2014 defines a protocol for the physical layer (PHY) and the data link layer in order to construct a reliable and high-speed data transmission network between devices on industrial sites such as factories and plants. This network specification provides a standardized protocol to provide a framework for various industrial devices to establish a simple, low-cost, energy-efficient, and high-speed network between them. In order to fulfil the service requirements of the factories and large plants, this network specification is designed to enable devices to establish a network by themselves without help of any infrastructure and reliably exchange various kinds of data, including real-time audio and video data, between them. In addition to high transmission rates, Quality of Service (QoS) for multimedia data - such as video - is also provided. The devices mentioned in ISO/IEC 24771:2014 refer to equipment that is and can be used in industrial sites such as factories and automated assembly lines. Such devices include PLC (Programmable Logic Controller), and CNC (Computerized Numerical Controller) and manufacturing robots. However, beyond such conventional devices, devices mentioned in this International Standard include personal IT devices that workers may carry and use while working, including cellular phones, personal industrial digital assistants (PDA), and laptop PCs.

Technologies de l'information — Télécommunications et échange d'information entre systèmes — Norme MAC/PHY pour un réseau ad hoc sans fil qui supporte QoS dans un environnement de travail industriel

General Information

• Status: Published
• Publication Date: 03-Aug-2014
• ICS: 35.110 - Networking
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 9093 - International Standard confirmed
• Start Date: 23-May-2025
• Completion Date: 30-Oct-2025

Relations

• Consolidated By: ISO 2589:2016 - Leather - Physical and mechanical tests - Determination of thickness
• Effective Date: 06-Jun-2022
• Revises: ISO/IEC 24771:2009 - Information technology - Telecommunications and information exchange between systems - MAC/PHY standard for ad hoc wireless network to support QoS in an industrial work environment
• Effective Date: 06-Aug-2011

Overview

ISO/IEC 24771:2014 defines a MAC/PHY protocol for ad hoc wireless networks in industrial work environments. The standard specifies physical-layer (PHY) and data-link-layer (MAC) functions to enable devices on factory floors, plants, and automated assembly lines to form self‑organizing, high‑speed, energy‑efficient networks without infrastructure. It focuses on reliable data transmission and Quality of Service (QoS) for multimedia (real‑time audio/video) and supports a wide range of industrial devices from PLCs, CNCs and robots to worker‑carried IT devices (cell phones, PDAs, laptops).

Key topics and technical requirements

• Ad hoc network operation: Self‑forming and self‑healing network behavior; master handover to maintain network continuity.
• MAC/PHY specification: Detailed service access points (MLME, PLME, PD‑SAP), frame formats, and PHY enumerated descriptions to ensure interoperability.
• Quality of Service (QoS): Mechanisms for stream creation/management and prioritized handling of multimedia streams.
• Binary CDMA technology: PHY-level access method referenced as a key characteristic for robust multi‑access in industrial environments.
• Media access control: Contention and allocation periods (beacon, contention, allocation), RTS/CTS, ACK, and isochronous vs. asynchronous data handling.
• Synchronization and timing: Superframe/beacon structures and network synchronization to support real‑time traffic.
• Security and key management: Procedures for membership, key establishment, distribution, and security management.
• Power management: Sleep-state notifications, power saving modes, and transmit-power adjustment for energy efficiency.
• Management interfaces and primitives: MLME/PLME GET/SET primitives, MAC PIB groups (authentication, association, network security) for device and network management.
• Frame and information blocks: Standardized MAC frame header/body formats, station UID/name/type, capability descriptors, and vendor extensions.

Practical applications and users

Who uses ISO/IEC 24771:2014:

• Industrial automation engineers designing wireless links for control and monitoring.
• Device manufacturers (PLCs, CNCs, industrial robots, HMIs) implementing interoperable MAC/PHY stacks.
• Network architects and integrators deploying ad hoc factory networks where infrastructure is impractical.
• OT/IT teams requiring QoS for video surveillance, remote operator video, and low‑latency control.
• Safety and compliance officers seeking a standards‑based approach to industrial wireless reliability and security.

Benefits:

• Enables low‑cost, energy‑efficient wireless networks in harsh industrial sites.
• Supports real‑time multimedia and control traffic with defined QoS.
• Facilitates vendor interoperability through standardized frame formats and management interfaces.

Related standards

For broader compliance and integration, consult other ISO/IEC telecommunications and information‑exchange standards in the ISO catalogue that address complementary layers and system architectures.

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 24771
Second edition
2014-08-01
Information technology —
Telecommunications and information
exchange between systems — MAC/PHY
standard for ad hoc wireless network to
support QoS in an industrial work
environment
Technologies de l'information — Télécommunications et échange
d'information entre systèmes — Norme MAC/PHY pour un réseau ad
hoc sans fil qui supporte QoS dans un environnement de travail
industriel
Reference number
©
ISO/IEC 2014
©  ISO/IEC 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any
means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission.
Permission can be requested from either ISO at the address below or ISO’s member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO/IEC 2014 – All rights reserved

Contents Page
1 Scope . 1
2 Normative references . 1
3 Terms and definitions, and abbreviations . 2
3.1 Terms and definitions . 2
3.2 List of Abbreviations . 3
4 Overview . 7
4.1 Characteristics . 7
4.1.1 Ad-hoc network . 7
4.1.2 Quality of Service . 7
4.1.3 Binary CDMA technology . 7
4.2 Components of network . 7
4.2.1 Station . 8
4.2.2 Resources . 8
4.3 Functional overview . 8
4.3.1 Network synchronization . 9
4.3.2 Data transmission . 9
4.3.3 Security . 10
4.3.4 Power management . 11
4.3.5 Master handover . 11
4.4 Summary of operations . 11
4.4.1 Broadcasting during the beacon period . 11
4.4.2 Random access during the contention period . 11
4.4.3 Exclusive access during the allocation period . 11
4.5 Summary of states . 12
4.5.1 Establishing the network . 12
4.5.2 Associating with the network . 12
4.5.3 Security membership and key establishment. 12
4.5.4 Data transfer . 12
4.5.5 Master handover . 12
4.5.6 Disassociating from the network . 13
4.5.7 Terminating the network . 13
5 Inter-layer interfaces . 14
5.1 Summary . 14
5.2 General format of management primitives . 14
5.2.1 MLME-GET.request and PLME-GET.request . 15
5.2.2 MLME-GET.confirm and PLME-GET.confirm . 16
5.2.3 MLME-SET.request and PLME-SET.request . 16
5.2.4 MLME-SET.confirm and PLME-SET.confirm . 16
5.3 MLME SAP . 17
5.3.1 Reset . 18
5.3.2 Scan . 19
5.3.3 Startup of network . 21
5.3.4 Synchronization . 22
5.3.5 Association . 24
5.3.6 Disassociation . 27
5.3.7 Key request. 29
5.3.8 Key distribution . 31
5.3.9 Security management . 34
5.3.10 Master handover . 38
5.3.11 Data request . 40
5.3.12 Network node data probe . 42
5.3.13 Strean creation, modification, termination . 44
© ISO/IEC 2014 – All rights reserved iii

5.3.14 Channel state. 48
5.3.15 Remote scan . 50
5.3.16 Network parameter modification . 53
5.3.17 Adjustment of power . 55
5.3.18 Power saving . 56
5.4 MAC management . 58
5.4.1 MAC PIB master group . 58
5.4.2 MAC PIB attributes group . 59
5.4.3 MAC PIB authentication group . 59
5.4.4 MAC PIB association group . 59
5.4.5 MAC PIB network security group . 60
5.5 MAC SAP . 60
5.5.1 MAC-ASYNC-DATA.request . 61
5.5.2 MAC-ASYNC-DATA.confirm . 62
5.5.3 MAC-ASYNC-DATA.indication . 62
5.5.4 MAC-ISOCH-DATA.request . 63
5.5.5 MAC-ISOCH-DATA.confirm . 63
5.5.6 MAC-ISOCH-DATA.indication . 64
5.6 PHY specification . 64
5.6.1 PD-SAP . 64
5.6.2 PLME-SAP. 74
5.6.3 Physical layer enumerated description . 79
6 Mac frame format . 81
6.1 Overview . 81
6.2 General format of MAC frames . 81
6.2.1 Frame header . 82
6.2.2 Frame body . 85
6.3 Frame formats . 86
6.3.1 Beacon . 86
6.3.2 Acknowledgement . 88
6.3.3 Command . 89
6.3.4 Data (stream or non-stream) . 90
6.3.5 RTS (Request To Send) . 90
6.3.6 CTS (Clear To Send) . 91
6.4 Information block . 91
6.4.1 Station UID . 92
6.4.2 Station name. 92
6.4.3 Station type. 92
6.4.4 Network synchronization . 92
6.4.5 Capabilities . 93
6.4.6 Maximum supported time slot . 93
6.4.7 Maximum transmit power . 94
6.4.8 Resource allocation . 94
6.4.9 New master notification . 95
6.4.10 Sleep state notification . 95
6.4.11 Vendor specific . 95
6.5 Command block . 95
6.5.1 Network management . 97
6.5.2 Stream management . 99
6.5.3 Power management . 103
6.5.4 Key management . 104
6.5.5 Security management . 105
6.5.6 Vendor specific . 105
6.5.7 Other . 106
7 MAC feature description . 110
7.1 Network formation and association . 110
7.1.1 Channel scanning . 110
7.1.2 Network ID . 111
7.1.3 Association . 111
© ISO/IEC 2014 – All rights reserved iv

7.1.4 Disassociation . 111
7.1.5 Master handover . 112
7.2 Media access . 112
7.2.1 Code assignment . 112
7.2.2 Inter-frame space . 112
7.2.3 Access during the contention period . 113
7.2.4 Access during the allocation period . 113
7.3 Synchronization . 114
7.3.1 Superframe synchronization . 114
7.3.2 Beacon generation . 115
7.3.3 Beacon reception . 115
7.3.4 Synchronization . 115
7.4 Resource allocation . 115
7.4.1 Transmission of synchronous data . 115
7.4.2 Asynchronous data transmission . 117
7.5 Fragmentation and defragmentation . 117
7.6 Acknowledgement and retransmission . 118
7.6.1 No acknowledgement . 118
7.6.2 Immediate acknowledgement . 118
7.6.3 Delayed acknowledgement . 118
7.6.4 Implicit acknowledgement . 118
7.6.5 Retransmission . 118
7.7 Power saving . 119
7.7.1 Saving power in a connected state . 119
7.7.2 Sleep state . 119
7.8 Dynamic channel management . 119
7.8.1 Channel state probe . 119
7.8.2 Remote Channel state probe . 119
7.8.3 Frequency channel change . 120
7.9 MAC parameters . 120
8 Security . 121
8.1 Security mechanisms . 121
8.1.1 Security membership and key establishment. 121
8.1.2 Key transport . 121
8.1.3 Data encryption . 121
8.1.4 Data integrity . 121
8.1.5 Beacon integrity protection . 122
8.1.6 Command integrity protection. 122
8.1.7 Freshness protection . 122
8.2 Security modes . 122
8.2.1 Security mode 0 . 122
8.2.2 Security mode 1 . 122
8.2.3 Security mode 2 . 123
8.3 Security Support . 123
8.3.1 Changes in the network group data key . 123
8.3.2 Joining a secure network . 123
8.3.3 Secure frame generation . 124
8.3.4 Secure frame reception . 124
8.3.5 Retransmission detect . 125
8.3.6 Key selection . 125
8.4 Key management protocol . 128
8.4.1 Key distribution protocol . 128
8.4.2 Key request protocol . 130
8.5 CCM mode . 131
8.5.1 Overview . 131
8.5.2 Nonce . 131
8.5.3 Inputs . 132
9 General specifications . 135
9.1 General requirements . 135
© ISO/IEC 2014 – All rights reserved v

9.1.1 Operating frequency range . 135
9.1.2 PHY layer timing . 136
9.1.3 Receive-to-transmit turnaround time . 137
9.1.4 Transmit-to-receive turnaround time . 137
9.1.5 Channel switch time . 137
9.1.6 Maximum frame size . 137
9.2 PHY Protocol Data Unit (PDU) format . 137
9.2.1 General format . 137
9.2.2 Preamble . 138
9.2.3 PHY Header. 139
9.2.4 PHY payload . 140
9.3 Modulation and coding . 141
9.3.1 Spreading code . 141
9.3.2 QPSK modulation . 142
9.3.3 Constant envelope coding . 142
9.3.4 Modulation methods for PHY PDU . 145
9.3.5 Data rate . 146
9.3.6 QPSK Modulation and constellation . 146
9.4 PHY layer constants and PHY PIB attribute . 147
9.5 Transmitter specification . 147
9.5.1 Error vector magnitude (EVM) definition . 147
9.5.2 EVM calculated values . 148
9.5.3 Transmitter power spectrum mask . 148
9.5.4 Signal waveform filter . 149
9.5.5 Error tolerance for carrier frequency . 149
9.5.6 Transmitter data rate . 149
9.5.7 Synchronization . 149
9.5.8 Transmitter response time . 150
9.5.9 RF carrier suppression . 150
9.5.10 Transmit power . 150
9.6 Receiver specifications . 150
9.6.1 Error rate criteria . 150
9.6.2 Receiver sensitivity . 151
9.6.3 Maximum input power . 151
9.6.4 Receiver Energy detection (ED) . 151
9.6.5 Clear channel assessment (CCA) . 151
9.6.6 Received CCA performance. 151
9.6.7 Received Signal Strength Index . 151
9.6.8 Link Quality Index (LQI) . 152
Annex A (informative) Example scheduler and admission control . 153
A.1 Scheduling algorithm . 153
A.2 Admission control Algorithm . 154

© ISO/IEC 2014 – All rights reserved vi

List of Figures
FIGURE 1- NETWORK . 8
FIGURE 2 - SUPERFRAME . 9
FIGURE 3 - PROTOCOL STACK CONFIGURATION. 14
FIGURE 4 - TRANSMISSION ORDER . 81
FIGURE 5 - FORMAT OF MAC FRAME . 82
FIGURE 6 - NON-SECURE MAC FRAME BODY FORMAT . 82
FIGURE 7 - SECURE MAC FRAME BODY FORMAT. 82
FIGURE 8 - FORMAT OF FRAME CONTROL FIELDS . 82
FIGURE 9 - FORMAT OF STREAM ID FIELD . 84
FIGURE 10 - NON-SECURE BEACON FRAME FORMAT . 86
FIGURE 11 - SECURE BEACON FRAME FORMAT . 87
FIGURE 12 - IMMEDIATE ACKNOWLEDGEMENT FRAME FORMAT . 88
FIGURE 13 - DELAYED ACKNOWLEDGEMENT FRAME PAYLOAD FORMAT . 89
FIGURE 14 - FORMAT OF RECORD FOR STREAM-M . 89
FIGURE 15 - NON-SECURE COMMAND FRAME FORMAT . 89
FIGURE 16 - COMMAND BLOCK FORMAT . 90
FIGURE 17 - FORMAT OF SECURE COMMAND FRAME. 90
FIGURE 18 - NON-SECURE DATA FRAME FORMAT . 90
FIGURE 19 - SECURE DATA FRAME FORMAT . 90
FIGURE 20 - RTS FRAME FORMAT . 91
FIGURE 21 - CTS FRAME FORMAT . 91
FIGURE 22 - INFORMATION BLOCK FORMAT . 92
FIGURE 23 - STATION UID INFORMATION BLOCK FORMAT . 92
FIGURE 24 - STATION NAME INFORMATION BLOCK FORMAT . 92
FIGURE 25 - STATION TYPE INFORMATION BLOCK FORMAT . 92
FIGURE 26 - NETWORK SYNCHRONIZATION INFORMATION BLOCK FORMAT . 92
FIGURE 27 - CAPABILITY INFORMATION BLOCK FORMAT . 93
FIGURE 28 - CAPABILITY FIELD FORMAT . 93
FIGURE 29 - MAXIMUM SUPPORT TIMESLOT INFORMATION BLOCK FORMAT . 93
FIGURE 30 - MAXIMUM TRANSMIT POWER INFORMATION BLOCK FORMAT . 94
FIGURE 31 - RESOURCE ALLOCATION INFORMATION BLOCK FORMAT . 94
FIGURE 32 - RESOURCE ALLOCATION BLOCK FORMAT . 94
FIGURE 33 - NEW MASTER NOTIFICATION INFORMATION BLOCK FORMAT . 95
FIGURE 34 - SLEEP STATE NOTIFICATION INFORMATION BLOCK FORMAT . 95
FIGURE 35 - VENDOR SPECIFIC INFORMATION ELEMENT FORMAT . 95
FIGURE 36 - COMMAND BLOCK FORMAT . 96
FIGURE 37 - ASSOCIATE REQUEST COMMAND BLOCK FORMAT. 97
FIGURE 38 - ASSOCIATION RESPONSE COMMAND BLOCK FORMAT . 97
FIGURE 39 - DISASSOCIATION REQUEST PAYLOAD FORMAT . 98
FIGURE 40 - MASTER HANDOVER COMMAND BLOCK FORMAT . 99
FIGURE 41 - RESOURCE ALLOCATION REQUEST COMMAND BLOCK FORMAT . 100
FIGURE 42 - RESOURCE ALLOCATION REQUEST RECORD FORMAT . 100
FIGURE 43 - RESOURCE ALLOCATION RESPONSE COMMAND BLOCK FORMAT. 100
FIGURE 44 - RESOURCE ALLOCATION MODIFICATION COMMAND BLOCK FORMAT. 101
FIGURE 45 - RESOURCE ALLOCATION MODIFICATION REQUEST RECORD FORMAT . 101
FIGURE 46 - RESOURCE ALLOCATION TERMINATION COMMAND BLOCK FORMAT . 102
FIGURE 47 - DELAYED ACKNOWLEDGEMENT RESYNCHRONIZATION COMMAND BLOCK FORMAT . 102
FIGURE 48 - DELAYED ACKNOWLEDGEMENT RESYNCHRONIZATION COMMAND RECORD FORMAT . 102
FIGURE 49 - SLEEP STATE REQUEST COMMAND BLOCK FORMAT . 103
FIGURE 50 - SLEEP STATE RESPONSE COMMAND BLOCK FORMAT . 103
FIGURE 51 - ACTIVATION INDICATION COMMAND BLOCK FORMAT . 104
FIGURE 52 - TRANSMIT POWER ADJUSTMENT COMMAND BLOCK FORMAT . 104
FIGURE 53 - KEY REQUEST COMMAND FORMAT . 104
FIGURE 54 - REQUEST KEY RESPONSE COMMAND FORMAT . 104
© ISO/IEC 2014 – All rights reserved vii

FIGURE 55 - REQUEST KEY RESPONSE COMMAND FORMAT . 105
FIGURE 56 - REQUEST KEY RESPONSE COMMAND FORMAT . 105
FIGURE 57 - VENDOR SPECIFIC SECURITY INFORMATION FORMAT . 105
FIGURE 58 - VENDOR SPECIFIC INFORMATION ELEMENT FORMAT . 106
FIGURE 59 - STATION INFORMATION REQUEST COMMAND BLOCK FORMAT . 106
FIGURE 60 - STATION INFORMATION RESPONSE COMMAND BLOCK FORMAT . 106
FIGURE 61 - STATION INFORMATION BLOCK FORMAT . 106
FIGURE 62 - DATA QUERY COMMAND BLOCK FORMAT . 107
FIGURE 63 - CHANNEL STATE REQUEST COMMAND BLOCK FORMAT . 107
FIGURE 64 - CHANNEL STATE RESPONSE COMMAND BLOCK FORMAT . 107
FIGURE 65 - REMOTE CHANNEL SCAN REQUEST COMMAND BLOCK FORMAT . 108
FIGURE 66 - REMOTE CHANNEL SCAN RESPONSE COMMAND BLOCK FORMAT . 108
FIGURE 67 - CHANNEL INFORMATION BLOCK FORMAT . 108
FIGURE 68 - APPLICATION SPECIFIC COMMAND FORMAT . 109
FIGURE 69 - ASSOCIATION PROCESS . 111
FIGURE 70 - INTER-FRAME SPACE IN THE ALLOCATED TIME SLOTS . 114
FIGURE 71 - SUPERFRAME SYNCHRONIZATION .
...