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 J.223.2 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (10/2016) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Interactive systems for digital television distribution
2、 Cabinet DOCSIS (C-DOCSIS) system specification Recommendation ITU-T J.223.2 Rec. ITU-T J.223.2 (10/2016) i Recommendation ITU-T J.223.2 Cabinet DOCSIS (C-DOCSIS) system specification Summary Recommendation ITU-T J.223.2 defines the system architecture, functional modules within the cabinet data ove
3、r cable service interface specification (C-DOCSIS) system, three C-DOCSIS systems utilizing the functional modules and the data and control interfaces between these modules for each system. It also defines general device requirements for the three C-DOCSIS systems. With a C-DOCSIS system, the module
4、s that perform the physical layer and data link layer functions can be deployed in the optical nodes of the hybrid fibre and coaxial (HFC) cable network. This Recommendation is technically identical to the ETSI ES 203 312 standard. History Edition Recommendation Approval Study Group Unique ID* 1.0 I
5、TU-T J.223.2 2016-10-14 9 11.1002/1000/13051 Keywords C-DOCSIS, DOCSIS. * 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 J.223
6、.2 (10/2016) 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 respons
7、ible for studying 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
8、-T study groups 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
9、 basis with 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 manda
10、tory provisions (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. Th
11、e use of such 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
12、 no position 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 not received notice of intellectual propert
13、y, protected by 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 2017 All rights reserved. N
14、o part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T J.223.2 (10/2016) 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 Abbrev
15、iations and acronyms 2 5 Conventions 3 6 Overview . 3 7 C-DOCSIS system and characteristics . 5 7.1 System definition and description 5 7.2 Characteristics 5 7.3 Relationship to ETSI ES 203 312 . 6 Appendix I Functional modules and system devices of Cabinet DOCSIS (C-DOCSIS) System. 7 I.1 Introducti
16、on 7 I.2 Functional modules and interfaces . 7 I.3 System devices . 9 Bibliography. 12 Rec. ITU-T J.223.2 (10/2016) 1 Recommendation ITU-T J.223.2 Cabinet DOCSIS (C-DOCSIS) system specification 1 Scope This Recommendation describes a method for distributed deployment and centralized control of a DOC
17、SIS cable broadband access system, referred to as cabinet data over cable service interface specification (C-DOCSIS). C-DOCSIS has been developed to meet the operability and manageability requirements for cable networks that offer a variety of high-bandwidth services and provide quality of service (
18、QoS) guarantees for these services in a distributed architecture. C-DOCSIS applies to the architecture and operations, administration and management (OAM) of cable broadband access networks. This Recommendation defines the functional modules within the C-DOCSIS system, three C-DOCSIS system architec
19、tures utilizing the functional modules and the data and control interfaces between these modules for each architecture. It also defines general device requirements for the different C-DOCSIS architectures. This Recommendation is technically identical to ETSI ES 203 312. 2 References The following IT
20、U-T Recommendations and other references contain provisions which, 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 Recommendati
21、on are therefore encouraged to investigate the possibility of applying 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
22、, as a stand-alone document, the status of a Recommendation. ITU-T J.210 Recommendation ITU-T J.210 (2006), Downstream RF interface for cable modem termination systems. ITU-T J.222.1 Recommendation ITU-T J.222.1 (2007), Third-generation transmission systems for interactive cable television services
23、IP cable modems: Physical layer specification. ITU-T J.222.2 Recommendation ITU-T J.222.2 (2007), Third-generation transmission systems for interactive cable television services IP cable modems: MAC and Upper Layer protocols. ITU-T J.222.3 Recommendation ITU-T J.222.3 (2007), Third-generation transm
24、ission systems for interactive cable television services IP cable modems: Security services. ETSI ES 203 312 ETSI ES 203 312 V1.1.1 (2015), Integrated broadband cable telecommunication networks (CABLE); Cabinet DOCSIS (C-DOCSIS) System Specification. 2 Rec. ITU-T J.223.2 (10/2016) 3 Definitions 3.1
25、Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 C-DOCSIS system b-ITU-T J.223.1: The C-DOCSIS system consists of the CMC controller, CMC, and C-DOCSIS CM. It implements broadband data access and forwarding, service configuration, as well as management an
26、d maintenance of coaxial cable networks. 3.1.2 CMC b-ITU-T J.223.1: The cable media converter (CMC) converts data from a coaxial cable network to a packet digital optical network (such as PON or Ethernet). The CMC connects to a cable modem (CM) through the coaxial cable network in the downstream dir
27、ection and to the CMC controller through the packet digital optical network in the upstream direction. 3.1.3 CMC controller b-ITU-T J.223.1: The CMC controller forwards upstream and downstream service data and manages the configuration of the CMC. 3.1.4 service flow b-ITU-T J.112 Annex B: A MAC-laye
28、r transport service which: provides unidirectional transport of packets from the upper layer service entity to the RF; shapes, polices, and prioritizes traffic according to QoS traffic parameters defined for the Flow. 3.2 Terms defined in this Recommendation This Recommendation defines the following
29、 terms: 3.2.1 C-DOCSIS management messages (CDMM): The C-DOCSIS management messages (CDMMs) are used for exchanging configurations, status, and management information between the system control module and the radio frequency interface (RFI) module. 3.2.2 C-DOCSIS CM: A cable modem (CM) that complies
30、 with the CM requirements of DOCSIS 3.0. 3.2.3 C-DOCSIS CMTS: A cable modem termination system (CMTS) that complies with the CMTS requirements of DOCSIS 3.0. In the context of this specification, it consists of a coax media converter (CMC) controller and a CMC or multiple CMCs operating together. 3.
31、2.4 C-DOCSIS data tag (CDT): As defined in the C-DOCSIS system, C-DOCSIS data tags (CDTs) are used to identify a service flow to which each data packet belongs. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: C-DOCSIS Cabinet DOCSIS CCI Control and Cla
32、ssifier Interface CDMM C-DOCSIS Management Message CDT C-DOCSIS Data Tag CLI Command Line Interface CM Cable Modem CMC Coax Media Converter CMTS Cable Modem Termination System CoS Class of Service CPE Customer Premises Equipment DHCP Dynamic Host Configuration Protocol Rec. ITU-T J.223.2 (10/2016) 3
33、 DOCSIS Data Over Cable Service Interface Specification EPON Ethernet Passive Optical Network FTTx Fibre To The x, where x indicates the final location on the user side of any one of a variety of optical fibre architectures, e.g., fibre to the building (FTTB), fibre to the curb (FTTC), fibre to the
34、premises (FTTP) GE Gigabit Ethernet GPON Gigabit-capable Passive Optical Network HFC Hybrid Fibre and Coaxial IP Internet Protocol LLC Logical Link Control MAC Media Access Control MAN Metropolitan Area Network MPI Main Path Interface NMS Network Management System NSI Network Side Interface OAM Oper
35、ations, Administration and Maintenance OLT Optical Line Terminal OMI Operation and Management Interface ONU Optical Network Unit PHY Physical Layer PON Passive Optical Network QoS Quality of Service RF Radio Frequency RFI Radio Frequency Interface SNMP Simple Network Management Protocol SNR Signal-t
36、o-Noise Ratio TCP Transmission Control Protocol UDP User Datagram Protocol VLAN Virtual Local Area Network 5 Conventions The keywords “is/are required to“ indicate a requirement which must be strictly followed and from which no deviation is permitted if conformance to this Recommendation is to be cl
37、aimed. 6 Overview Cabinet data over cable service interface specification (C-DOCSIS) is based on proven DOCSIS 3.0 technology and with objectives of carrying high-bandwidth services and enabling cost effective system operation. C-DOCSIS presents a logical architecture of distributed deployment and c
38、entralized management for the cable broadband access system. It defines the logical functional modules of the system as well as related interfaces and protocols that support the architecture, through 4 Rec. ITU-T J.223.2 (10/2016) different combinations of the logical functional modules; C-DOCSIS sp
39、ecifies three different system implementations and the corresponding systems devices. As the key to implementing the architecture of distributed deployment and centralized management, C-DOCSIS defines the C-DOCSIS cable modem termination system (CMTS) with a coax media converter (CMC) and the CMC co
40、ntroller to achieve the DOCSIS CMTS functionality, as shown in Figure 1. The CMC controller implements the metropolitan area network (MAN) interfaces and the CMC implements the radio frequency (RF) interfaces specified in ITU-T J.222.1, ITU-T J.222.2, ITU-T J.222.3 and ITU-T J.210, which are a part
41、of C-DOCSIS. The CMC controller and CMC can be interconnected via a layer-2 or layer-3 network, such as digital optical packet network. Figure 1 C-DOCSIS CMTS network diagram The CMC controller is deployed in the central office or headend to realize the centralized system management, configuration a
42、nd scheduling, thus enabling the C-DOCSIS CMTS to inherit the advantages of a centralized DOCSIS CMTS system. The CMC itself is distributed; it is deployed in the optical node, enabling the C-DOCSIS CMTS to introduce the space-division multiplexing on top of the time-division multiplexing and freque
43、ncy-division multiplexing utilized by the DOCSIS CMTS to achieve higher access bandwidth per user, which is highly desirable for the applications with large upstream bandwidth consumption. With the distributed deployment of CMC and coupled with the technical advantages of the digital optical packet
44、network, a C-DOCSIS system can fully utilize the resources of the hybrid fibre and coaxial (HFC) network and existing cable modems (CMs) to realize a cost-effective system deployment and operation, it reduces the return noise and enhances the CMTS downlink channel signal-to-noise ratio (SNR), and is
45、 thus able to implement a higher order modulation scheme to obtain higher bandwidth. C-DOCSIS specifies three types of CMC controllers and CMCs to implement the C-DOCSIS CMTS. 1) Type I CMC implements all the DOCSIS CMTS functions, and type I CMC controller implements high-level and partial-system m
46、anagement and configuration functions; 2) Type II CMC implements the data forwarding and CM access functions, and Type II CMC controller implements the system management, configuration, and scheduling functions; 3) Type III CMC only implements the C-DOCSIS CMTS physical layer (PHY) function, and the
47、 CMC controller implements the rest of the functions of the C-DOCSIS CMTS. C-DOCSIS system architecture is an open architecture, which nicely aligns the DOCSIS system with the HFC migration toward the fibre to the x (FTTx) network. The implementation of the C-DOCSIS system is flexible. The CMC contr
48、oller and CMC can be realized as stand-alone devices in accordance with the provisions of the specification, or they can be integrated with other existing devices to meet the needs of future development, such as the combination of CMC controller with optical line terminal Rec. ITU-T J.223.2 (10/2016
49、) 5 (OLT), router and switches, and the combination of CMC with optical network unit (ONU), light stations, and Internet protocol quadrature amplitude modulation (IPQAM)s. 7 C-DOCSIS system and characteristics 7.1 System definition and description The C-DOCSIS system defined in this Recommendation consists of C-DOCSIS CMTSs and C-DOCSIS CMs. C-DOCSIS CMTSs consist of CMC controllers and CMCs as shown in Figure 2. This Recommendation defines the functional modules, interface, and requirements of C-DOCSIS CMTSs in detail, whic
