1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T Y.4451 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2016) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet of things an
2、d smart cities and communities Frameworks, architectures and protocols Framework of constrained device networking in the IoT environments Recommendation ITU-T Y.4451 ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS, INTERNET OF
3、THINGS AND SMART CITIES GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Network aspects Y.300Y.399 Interfaces and protocols Y.400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600Y.699 Security Y.700
4、Y.799 Performances Y.800Y.899 INTERNET PROTOCOL ASPECTS General Y.1000Y.1099 Services and applications Y.1100Y.1199 Architecture, access, network capabilities and resource management Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network performance Y.1500Y.1599
5、 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 IPTV over NGN Y.1900Y.1999 NEXT GENERATION NETWORKS Frameworks and functional architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities a
6、nd service architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Enhancements to NGN Y.2300Y.2399 Network management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Packet-based Networks Y.2600Y.2699 Security Y.2700Y.2799 Gener
7、alized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 FUTURE NETWORKS Y.3000Y.3499 CLOUD COMPUTING Y.3500Y.3999 INTERNET OF THINGS AND SMART CITIES AND COMMUNITIES General Y.4000Y.4049 Definitions and terminologies Y.4050Y.4099 Requirements and use cases Y.4100Y.4249 Infrastructur
8、e, connectivity and networks Y.4250Y.4399 Frameworks, architectures and protocols Y.4400Y.4549 Services, applications, computation and data processing Y.4550Y.4699 Management, control and performance Y.4700Y.4799 Identification and security Y.4800Y.4899 Evaluation and assessment Y.4900Y.4999 For fur
9、ther details, please refer to the list of ITU-T Recommendations. Rec. ITU-T Y.4451 (09/2016) i Recommendation ITU-T Y.4451 Framework of constrained device networking in the IoT environments Summary In Internet of things (IoT) environments, constrained devices, equipped with various low-power wireles
10、s interfaces, have connection capability to locally available networks for the purpose of interacting with the real world. Constrained devices have many different characteristics. Recommendation ITU-T Y.4451 specifies the framework of constrained device networking in the Internet of things (IoT) env
11、ironments. This Recommendation therefore describes the concept and features of constrained device networking as well as network architectures of constrained device networking including functional requirements, such as fragmentation, reassembly, header compression, address configuration, network mana
12、gement, multi-hop routing protocol and higher layer considerations. This Recommendation specifies the framework of constrained device networking in the Internet of things (IoT) environments with respect to IoT device communications. This Recommendation describes the concept of constrained device net
13、working in the IoT environments and the communication of constrained devices. This Recommendation also describes network architecture and mechanisms of constrained device networking. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T Y.4451 2016-09-13 20 11.1002/1000/13026 Keyw
14、ords Constrained device networking, Internet of Things, IoT. * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T Y.4451 (09/2016)
15、 FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for stu
16、dying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study gro
17、ups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with
18、ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisi
19、ons (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of suc
20、h words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position
21、 concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by
22、patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2016 All rights reserved. No part of this p
23、ublication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T Y.4451 (09/2016) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acron
24、yms 2 5 Conventions 2 6 Overview of constrained device networking in the IoT environments . 3 6.1 IoT environments and constrained device networking . 3 6.2 General characteristics of constrained devices . 3 7 Communication features and attributes 4 7.1 Features of constrained devices in IoT environ
25、ment 4 7.2 Considerations for constrained device networking 4 8 Constrained device network architectures 5 8.1 Network components 5 8.2 Network topologies 5 8.3 Protocol stacks for constrained device networking 7 9 Functional requirements of constrained device networking . 8 9.1 Fragmentation and re
26、assembly . 8 9.2 Header compression . 9 9.3 Address configuration 9 9.4 Network management . 9 9.5 Higher layer considerations 9 9.6 Multi-hop routing protocol . 9 10 Security considerations . 9 Annex A Network scalability in constrained devices . 10 Annex B Mechanism for providing network stability
27、 through IP continuity of NFC devices in the Internet . 12 Bibliography. 15 Rec. ITU-T Y.4451 (09/2016) 1 Recommendation ITU-T Y.4451 Framework of constrained device networking in the IoT environments 1 Scope The scope of this Recommendation includes the following: An overview of constrained device
28、networking in the IoT environments. Communication of constrained devices. Architectures of constrained device networking. Functionalities of constrained device networking. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text,
29、constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of t
30、he Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.9959 Recommendation ITU-T G.99
31、59 (2015), Short range narrow-band digital radiocommunication transceivers PHY, MAC, SAR and LLC layer specifications. ITU-T Y.4000 Recommendation ITU-T Y.4000/Y.2060 (2012), Overview of the Internet of things. ITU-T Y.4109 Recommendation ITU-T Y.4109/Y.2061 (2012), Requirements for the support of m
32、achine-oriented communication applications in the next generation network environment. IETF RFC 4862 IETF RFC 4862 (2007), IPv6 Stateless Address Autoconfiguration. IETF RFC 4944 IETF RFC 4944 (2007), Transmission of IPv6 Packets over IEEE 802.15.4 Networks. IETF RFC 5225 IETF RFC 5225 (2008), RObus
33、t Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP-Lite. IETF RFC 6282 IETF RFC 6282 (2011), Compression Format for IPv6 Datagrams over IEEE 802.15.4-Based Networks. IETF RFC 6550 IETF RFC 6550 (2012), RPL: IPv6 Routing Protocol for Low-Power and Lossy Networks. IETF RFC
34、 7400 IETF RFC 7400 (2014), 6LoWPAN-GHC: Generic Header Compression for IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs). IETF RFC 7428 IETF RFC 7428 (2015), Transmission of IPv6 Packets over ITU-T G.9959 Networks. IETF RFC 7668 IETF RFC 7668 (2015), IPv6 over BLUETOOTH(R) Low Energy.
35、IETF RFC 7721 IETF RFC 7721 (2016), Security and Privacy Considerations for IPv6 Address Generation Mechanisms. 2 Rec. ITU-T Y.4451 (09/2016) 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 device ITU-T Y.4000: With regard to the Intern
36、et of things, this is a piece of equipment with the mandatory capabilities of communication and the optional capabilities of sensing, actuation, data capture, data storage and data processing. 3.1.2 Internet of things (IoT) ITU-T Y.4000: A global infrastructure for the information society, enabling
37、advanced services by interconnecting (physical and virtual) things based on existing and evolving interoperable information and communication technologies. NOTE 1 Through the exploitation of identification, data capture, processing and communication capabilities, the IoT makes full use of things to
38、offer services to all kinds of applications, whilst ensuring that security and privacy requirements are fulfilled. NOTE 2 From a broader perspective, the IoT can be perceived as a vision with technological and societal implications. 3.2 Terms defined in this Recommendation This Recommendation define
39、s the following terms: 3.2.1 constrained device: A device that has constraints on characteristics such as limited processing capability, small memory capability, limited battery power, short range and low bit rate. 3.2.2 adaptation layer: A layer that is required for binding the network layer and th
40、e datalink layer in low-power network technologies. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: BLE Bluetooth Low Energy IoT Internet of Things LLCP Logical Link Control Protocol LoWPAN Low-power Wireless Personal Area Network MP2P Multipoint-to-Po
41、int (MP2P) MTU Maximum Transmission Unit NFC Near Field Communication POS Personal Operating Space P2MP Point-to-Multipoint P2P Point-to-Point QoS Quality of Service SNMP Simple Network Management Protocol SSAP Source Service Access Point 5 Conventions None. Rec. ITU-T Y.4451 (09/2016) 3 6 Overview
42、of constrained device networking in the IoT environments 6.1 IoT environments and constrained device networking The ITU Report 2005 b-ITU Report states that Internet of things (IoT) can be defined as a vision First, in order to connect everyday objects and devices to large databases and networks a s
43、imple, unobtrusive and cost-effective system of item identification is indispensable. Second, data collection can of course benefit from the ability to detect changes in the physical status of things. Finally, advances in miniaturization and nanotechnology mean that smaller and smaller things will h
44、ave the ability to interact and connect. According to the vision of the IoT, the smaller things, i.e., constrained IoT devices, equipped with various low-power wireless interfaces (e.g., IEEE 802.15.4, Bluetooth low energy (BLE), near field communication (NFC), etc.), need to have connection capabil
45、ity to locally available networks for the purpose of interacting with the real world including non-constrained IoT devices, see example in Figure 1. Various types of advanced IoT services applications can be deployed using the different types of connections and interactions. Figure 1 Connected const
46、rained and non-constrained devices 6.2 General characteristics of constrained devices To develop the advanced IoT services and applications, various aspects of the requirements should be considered in advance. One such aspect is the type of constraint that characterizes the IoT devices. Constraint t
47、ypes for IoT devices are listed as follows: Limited processing capability: The constrained IoT devices have limited processing capability. For example, the smallest common low-power wireless personal area network (LoWPAN) nodes have 8-bit processors with clock rates of around 10 MHz. Other models ex
48、ist with 16-bit and 32-bit cores (typically ARM7), running at frequencies in the range of tens of MHz. Small memory capacity: In the case of monitoring and target-tracking IoT services, the constrained IoT devices have a limited memory capacity. These constrained IoT devices have a few kilobytes of
49、RAM with a few dozen kilobytes of ROM/flash memory. While 4 Rec. ITU-T Y.4451 (09/2016) memory sizes of nodes continue to grow, the nature of small memory capacity for the constrained IoT devices remains a challenge. Limited battery power and low power consumption: Wireless radios for mobile devices are normally battery-operated. For the sake of longevity, mobile devices should conserve energy and not waste the limited battery power. Short range: The personal operating
