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.4500.20 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (03/2018) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS, NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet of things an
2、d smart cities and communities Frameworks, architectures and protocols oneM2M WebSocket protocol binding Recommendation ITU-T Y.4500.20 ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS, NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES GLOBAL IN
3、FORMATION 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.700Y.799 Performances Y.800Y.899 INT
4、ERNET 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 Signalling Y.1600Y.1699 Operatio
5、n, 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 and service architecture Y.2200Y.2
6、249 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 Generalized mobility Y.2800Y.2899 Carr
7、ier 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 Infrastructure, connectivity and networks Y.42
8、50Y.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 further details, please refer to the
9、 list of ITU-T Recommendations. Rec. ITU-T Y.4500.20 (03/2018) i Recommendation ITU-T Y.4500.20 oneM2M WebSocket protocol binding Summary Recommendation ITU-T Y.4500.20 specifies the binding of Mca and Mcc primitives on to the WebSocket binding. Recommendation ITU-T Y.4500.20 specifies: procedures a
10、nd message formats for operating and closing of WebSocket connections; how request and response primitives are mapped into the payload of the WebSocket protocol. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T Y.4500.20 2018-03-01 20 11.1002/1000/13511 Keywords oneM2M, WebSo
11、cket. * 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.4500.20 (03/2018) FOREWORD The International Telecommunication Union
12、(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 studying technical, operating and tariff questions and
13、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 groups which, in turn, produce Recommendations on these
14、 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 ISO and IEC. NOTE In this Recommendation, the expres
15、sion “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 provisions (to ensure, e.g., interoperability or applicabil
16、ity) 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 such words does not suggest that compliance with the Re
17、commendation 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 concerning the evidence, validity or applicability
18、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 not received notice of intellectual property, protected by patents, which may be required to implement this
19、 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/. NOTE This Recommendation departs slightly from the usual editorial style of ITU-T Recommendatio
20、ns to preserve existing cross-referencing from external documents. ITU 2018 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T Y.4500.20 (03/2018) iii Table of Contents Page 1 Scope . 1 2 References . 1
21、 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 2 6 Overview on WebSocket Binding 3 6.1 Use of WebSocket 3 6.2 Binding Overview 3 7 Protocol Binding . 6 7.1 Introduction 6 7.2 WebSocket connection establishment
22、7 7.3 Closing WebSocket connection 10 7.4 Registration procedure 10 7.5 Handling of Non-Registration Request 10 7.6 Use of proxy servers . 10 8 Security Aspects . 11 Annex A oneM2M Specification Update and Maintenance Control Procedure . 12 Appendix I Example Procedures . 13 I.1 AE Registration and
23、creation of a Container child resource 13 Bibliography. 16 Rec. ITU-T Y.4500.20 (03/2018) 1 Recommendation ITU-T Y.4500.20 oneM2M WebSocket protocol binding 1 Scope This Recommendation specifies the binding of Mca and Mcc primitives on to the WebSocket binding. This Recommendation specifies: procedu
24、res and message formats for operating and closing of WebSocket connections; how request and response primitives are mapped into the payload of the WebSocket protocol. The Recommendation contains oneM2M Release 2 specification oneM2M WebSocket Protocol Binding V2.0.0 and is equivalent to standards of
25、 oneM2M partners including ARIB, ATIS b-ATIS.oneM2M.TS0020V200, CCSA, ETSI b-ETSI TS 118 120, TIA, TSDSI b-TSDSI STD T1.oneM2M TS-0020-2.0.0 , TTA b-TTAT.MM-TS.0020 v2.0.0 and TTC b-TTC TS-M2M-0020v2.0.0. 2 References The following ITU-T Recommendations and other references contain provisions which,
26、 through reference in this text, 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 appl
27、ying the most recent edition of the 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
28、 Y.4500.1 Recommendation ITU-T Y.4500.1 (2018), oneM2M Functional architecture. ITU-T Y.4500.4 Recommendation ITU-T Y.4500.4 (2018), oneM2M Service layer core protocol. ETSI TS 118 103 ETSI TS 118 103 V2.4.1 (2016), oneM2M; Security solutions (oneM2M TS-0003 version 2.4.1 Release 2). IETF RFC 6455 I
29、ETF RFC 6455 (2011), The WebSocket protocol. IETF RFC 7230 IETF RFC 7230 (2014), Hypertext transport protocol (HTTP/1.1): Message syntax and routing. IETF RFC 7692 IETF RFC 7692 (2015), Compression extensions for WebSocket. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the follo
30、wing terms defined elsewhere: 3.1.1 application entity (AE): b-ITU-T Y.4500.11 Represents an instantiation of application logic for end-to-end M2M solutions. 3.1.2 common services entity (CSE): b-ITU-T Y.4500.11 Represents an instantiation of a set of common service functions of the M2M environments
31、. Such service functions are exposed to other entities through reference points. 2 Rec. ITU-T Y.4500.20 (03/2018) 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 oneM2M WebSocket client (WS client): WebSocket client associated with an application entit
32、y or a common services entity capable of establishing the WebSocket connections. 3.2.2 oneM2M WebSocket server (WS server): WebSocket server associated with a common services entity which accepts requests to establish WebSocket connections. 4 Abbreviations and acronyms This Recommendation uses the f
33、ollowing abbreviations and acronyms: ADN Application Dedicated Node AE Application Entity ASN Application Service Node CBOR Concise Binary Object Representation CMDH Communication Management and Delivery Handling CRUDN Create-Retrieve-Update-Delete-Notify CSE Common Services Entity FQDN Fully Qualif
34、ied Domain Name GUID Globally Unique Identifier HTTP Hypertext Transport Protocol IN-CSE Infrastructure Node-Common Services Entity IP Internet Protocol JSON JavaScript Object Notation MN-CSE Middle Node-Common Services Entity NAT Network Address Translator SAEF Security Association Establishment Fr
35、amework TCP Transmission Control Protocol TLS Transport Layer Security URI Uniform Resource Identifier WS WebSocket WSS WebSocket Secure XML Extensible Markup Language 5 Conventions The keywords “shall“, “shall not“, “may“, “need not“, “should“, “should not“ in this Recommendation are to be interpre
36、ted as follows. Shall/shall not: Requirements: 1) effect on this Recommendation: this Recommendation needs to describe the required feature (i.e., specify a technical solution for the requirement); Rec. ITU-T Y.4500.20 (03/2018) 3 2) effect on products: every implementation (M2M solution that compli
37、es with this Recommendation) must support it; 3) effect on deployments: every deployment (M2M service based on this Recommendation) must use the standardized feature where applicable otherwise interoperability problems with other services could arise, for example. Should/should not: Recommendation 1
38、.) effect on this Recommendation: this Recommendation needs to describe a solution that allows the presence and the absence of the feature; 2) effect on products: an implementation may or may not support it; however, support is recommended; 3) effect on deployments: a deployment may or may not use i
39、t; however, usage is recommended. May/need not: Permission/option 1) effect on this Recommendation: this Recommendation needs to describe a solution that allows the presence and the absence of the required feature; 2) effect on products: an implementation may or may not support it; 3) effect on depl
40、oyments: a deployment may or may not use it. 6 Overview of WebSocket binding 6.1 Use of WebSocket This binding makes use of the WebSocket protocol IETF RFC 6455 to transport serialized representations of oneM2M request and response primitives over the Mca or Mcc reference points. Establishment of a
41、WebSocket connection shall be initiated by a WebSocket client by sending a handshake to a WebSocket server as specified in section 4 of IETF RFC 6455. Once the WebSocket connection is established, both the oneM2M request and response primitives can be exchanged bi-directionally between the two endpo
42、ints of the connection. Serialized representations of the request and response primitives shall be mapped in the Payload Data field of the WebSocket base framing protocol, as defined in section 5.2 of IETF RFC 6455. A WebSocket connection employs either a transmission control protocol/Internet proto
43、col (TCP/IP) or transport layer security (TLS) over a TCP/IP connection. The underlying TCP and TLS connections are established as the first step of the WebSocket handshake. 6.2 Binding overview WebSocket binding may be employed for communication between any two endpoints that can be connected over
44、the Mca, Mcc or Mcc interface reference points supported by the oneM2M architecture as shown in Figure 6.1-1 of oneM2M TS-0001 ITU-T Y.4500.1. When using the WebSocket protocol, one communication endpoint shall act as the WebSocket server. The WebSocket server listens for inbound handshake messages
45、arriving from any WebSocket client to which a WebSocket connection is not yet established. Whether a communication endpoint takes the role of the client or the server shall depend on the registration relationship between the communicating entities as follows: the registree shall always use a WebSock
46、et client, while the associated registrar shall always use a WebSocket server on the respective reference point. This implies that the application dedicated node (ADN) and application service node (ASN) always take the role of a WebSocket client when WebSocket binding is employed. A middle node-comm
47、on 4 Rec. ITU-T Y.4500.20 (03/2018) services entity (MN-CSE) uses a WebSocket server to communicate with its registrees and a WebSocket client to communicate with its own registrar which can be another MN-CSE or an infrastructure node-common services entity (IN-CSE). The IN-CSE provides a WebSocket
48、server functionality to communicate with all its registrees, i.e., within a service providers domain. On the Mcc reference points, i.e., for communication between IN-CSEs of different Service Provider domains, the IN-CSE shall provide both WebSocket client and server functionality. This enables any
49、IN-CSE to open a WebSocket connection to any IN-CSE of another Service Providers domain. Figure 6.2.-1 shows an example of an applicable system configuration. Figure 6.2-1 Example scenarios of WebSocket client and server configurations There exists a maximum of one WebSocket connection between two nodes. A WebSocket connection is established for the first time when the initial registration procedure of an entity to its registrar is performed. On an established W
