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.1106 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (07/2017) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Switched digital video over cable networks Requirement f
2、or radio over IP transmission system Recommendation ITU-T J.1106 Rec. ITU-T J.1106 (07/2017) i Recommendation ITU-T J.1106 Requirement for radio over IP transmission system Summary As cable television (TV) networks migrate to deep fibre or fibre to the home (FTTH) architecture, it is now easier to p
3、rovide bidirectional high-quality media services that require very high-speed digital transmission of various high-quality contents. As cable TV networks provide services by transmitting radio frequency (RF) signals between headend and a cable modem (CM), the configuration and devices of the cable T
4、V network are optimized for RF signal transmission. For migration to all-fibre access, the existing cable TV network devices of service operators (SOs), which provide broadcasting services and various data services through a TV network based on hybrid fibre coaxial (HFC) cable, are recommended for c
5、hange to new network devices. Therefore, a cost-effective solution for deployable and acceptable migration towards optic-based cable TV networks is required. Recommendation ITU-T J.1106 provides a cost-effective solution to convert HFC-based cable TV network devices into those based on optic cable.
6、History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T J.1106 2017-07-29 9 11.1002/1000/13287 Keywords Cable, optic, RoIP, TV * 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
7、example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T J.1106 (07/2017) 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 Stand
8、ardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible 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), wh
9、ich meets every four years, establishes the topics for study by the ITU-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
10、ITU-Ts purview, the necessary standards are prepared on a collaborative 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 Recommendat
11、ion is voluntary. However, the Recommendation may contain certain mandatory 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 “
12、must“ and the negative equivalents are used to express requirements. The 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
13、may involve the use of a claimed Intellectual Property Right. ITU takes 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 t
14、his Recommendation, ITU had received notice of intellectual property, 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 databa
15、se at http:/www.itu.int/ITU-T/ipr/. ITU 2017 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 J.1106 (07/2017) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 1 3.1 Terms defined
16、 elsewhere 1 3.2 Terms defined in this Recommendation . 1 4 Abbreviations and acronyms 1 5 Conventions 2 6 Overview . 2 7 Requirements 3 7.1 RoIP Terminal 3 7.2 RoIP Headend . 4 Bibliography. 5 Rec. ITU-T J.1106 (07/2017) 1 Recommendation ITU-T J.1106 Requirement for radio over IP transmission syste
17、m 1 Scope This Recommendation describes the functional requirements for radio over Internet protocol (RoIP) transmission systems based on data over cable service interface specifications (DOCSIS). The purpose of an RoIP system is to transmit data (DOCSIS based) over an upstream (US) radio frequency
18、(RF) signal from a cable modem (CM) to a cable modem termination system (CMTS) through Internet protocol (IP) transmission in an optic-based cable television (TV) network. 2 References None. 3 Definitions 3.1 Terms defined elsewhere None. 3.2 Terms defined in this Recommendation None. 4 Abbreviation
19、s and acronyms This Recommendation uses the following abbreviations and acronyms: CM Cable Modem CMTS Cable Modem Termination System DOCSIS Data Over Cable Service Interface Specifications DS Downstream FTTH Fibre To The Home HFC Hybrid Fibre Coaxial IP Internet Protocol OLT Optical Line Terminal OM
20、UX Optical Multiplexer RF Radio Frequency RoIP Radio over Internet Protocol SO Service Operator STB Set-Top Box TV Television US Upstream 2 Rec. ITU-T J.1106 (07/2017) 5 Conventions In this Recommendation: The keywords “is required to“ indicate a requirement which must be strictly followed and from
21、which no deviation is permitted if conformance to this document is to be claimed. The keywords “is recommended“ indicate a requirement which is recommended but which is not absolutely required. Thus this requirement need not be present to claim conformance. The keywords “is prohibited from“ indicate
22、 a requirement which must be strictly followed and from which no deviation is permitted if conformance to this document is to be claimed. The keywords “can optionally“ indicate an optional requirement which is permissible, without implying any sense of being recommended. This term is not intended to
23、 imply that the vendors implementation must provide the option and the feature can be optionally enabled by the network operator/service provider. Rather, it means the vendor may optionally provide the feature and still claim conformance with the specification. In the body of this document and its a
24、nnexes, the words shall, shall not, should, and may sometimes appear, in which case they are to be interpreted, respectively, as is required to, is prohibited from, is recommended, and can optionally. The appearance of such phrases or keywords in an appendix or in material explicitly marked as infor
25、mative are to be interpreted as having no normative intent. 6 Overview In order to transmit an RF signal through an optic-based cable TV network, optical amplitude modulation (AM) converting an RF signal into an analogue optical signal is required. However, since the unit price of an optical AM conv
26、erter is high, there is a heavy cost for service operators (SOs) to apply optical AM to all subscriber terminals. A new transmission technology that does not use or replaces optical AM is therefore needed. The proposed transmission technology can provide a cost-effective solution to adapt existing c
27、able TV network devices, based on hybrid fibre coaxial (HFC), for an optic-based cable TV network. An RoIP system is not required to equip an optical AM module to transmit a US RF signal because such a signal is transmitted through IP packets. As shown in Figure 1, the RoIP system consists of an RoI
28、P terminal and an RoIP headend. The RoIP terminal is located at the end point of an optic-based cable TV network and the RoIP headend is located between the CMTS and optical network end point such as an optical line terminal (OLT). It is required to synchronize and transmit US using a DOCSIS-based p
29、rotocol for IP transmission. The cable headend is required to convert a downstream (DS) RF signal of the CMTS into an optical signal, and transmit it to the CM. The RoIP terminal is required to convert an optical signal into an electrical RF signal, and transmit it to the cable set-top box (STB). Al
30、so, the RoIP terminal is required to convert an US RF signal into IP data, and transmit it to the RoIP headend. The RoIP headend is required to convert IP data into an RF signal, and transmit it to the CMTS. The RoIP terminal and RoIP headend are required to transmit a synchronized signal with a DOC
31、SIS-based TDMA scheme between the CMTS and CM. The RoIP headend is required to synchronize with the CMTS, and the RoIP terminal is required to synchronize with the CM. After receiving a US signal from the CM, the RoIP terminal has to obtain the acquisition time that is sent to the RF signal by the C
32、M. The time information is transmitted to the CMTS by the IP. When the RoIP terminal transmits a digitized RF signal and time information to the CMTS, bandwidth allocation information proposed by the CMTS for sending the signal requires reference by each CM. Rec. ITU-T J.1106 (07/2017) 3 Figure 1 Sy
33、stem architecture for radio over Internet protocol The RoIP system consists of two subsystems, namely the RoIP headend and the RoIP terminal. The function of the RoIP terminal subsystem is as follows: reception of an US RF signal from the CM; transmission of the digitized RF signal to the RoIP heade
34、nd over an optic-based cable TV network for IP transmission; synchronization with the CM; transmission of the DS RF signal to the CM. The function of the RoIP headend subsystem is as follows: reception of digitized RF data from RoIP terminals over IP-based networks; reconstruction of the RF signals
35、from the digitized RF data encapsulated in the IP packet; transmission of the RF signals to the CMTS; time synchronization with the CMTS. 7 Requirements 7.1 RoIP Terminal RoIP-Terminal-01 The RoIP Terminal subsystem is required to detect and acquire an RF signal from the CM. RoIP-Terminal-02 The RoI
36、P Terminal subsystem is required to convert an RF signal into digitized RF data. RoIP-Terminal-03 The RoIP Terminal subsystem is required to acquire timestamps of RF signals. RoIP-Terminal-04 The RoIP Terminal subsystem is required to packetize the IP and transmit RF signals. RoIP-Terminal-05 The Ro
37、IP Terminal subsystem is required to transmit the acquisition times of the RF signals. RoIP-Terminal-06 The RoIP Terminal subsystem is recommended to compress the digitized RF data. 4 Rec. ITU-T J.1106 (07/2017) RoIP-Terminal-07 The RoIP Terminal subsystem is required to synchronize the clock betwee
38、n the CM and RoIP terminal by using a DOCSIS management SYNC message. RoIP-Terminal-08 The RoIP Terminal subsystem is required to compensate network time by using the acquisition time of the RF signal and the bandwidth allocation information provided by the CMTS. RoIP-Terminal-09 The RoIP Terminal s
39、ubsystem is required to receive a DS RF overlay signal from the CMTS. RoIP-Terminal-10 The RoIP Terminal subsystem is required to convert from an optical to an electrical signal. RoIP-Terminal-11 The RoIP Terminal subsystem is required to transmit the RF signal to the CM. See b-ANSI/SCTE 135-1 b-ANS
40、I/SCTE 135-5 2009 for more information. 7.2 RoIP Headend RoIP-Headend-01 The RoIP Headend subsystem is recommended to decompress compressed digital RF data. RoIp-Headend-02 The RoIP Headend subsystem is required to buffer the digitized RF data to compensate for transmission delay variation. RoIP-Hea
41、dend-03 The RoIP Headend subsystem is required to schedule the RF signals according to the permitted time period. RoIP-Headend-04 The RoIP Headend subsystem is required to convert digitized RF data into an RF signal. RoIP-Headend-05 The RoIP Headend subsystem is required to transmit RF signals at a
42、scheduled time. RoIP-Headend-06 The RoIP Headend subsystem is required to synchronize clock between the CMTS and the RoIP headend using a DOCSIS management SYNC message. RoIP-Headend-07 The RoIP Headend subsystem is required to synchronize the network time using a ranging process. RoIP-Headend-08 Th
43、e RoIP Headend subsystem is required to process bandwidth allocation information provided by the CMTS. Rec. ITU-T J.1106 (07/2017) 5 Bibliography b-ANSI/SCTE 135-1 ANSI/SCTE 135-1 2013, DOCSIS 3.0 Part 1: Physical layer specification. b-ANSI/SCTE 135-5 2009 ANSI/SCTE 135-5 2009, DOCSIS 3.0 Part 5: C
44、able modem to customer premise equipment interface. Printed in Switzerland Geneva, 2017 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D Tariff and accounting principles and international telecommunication/ICT economic and policy issues Series E Overall network ope
45、ration, telephone service, service operation and human factors Series F Non-telephone telecommunication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and
46、transmission of television, sound programme and other multimedia signals Series K Protection against interference Series L Environment and ICTs, climate change, e-waste, energy efficiency; construction, installation and protection of cables and other elements of outside plant Series M Telecommunicat
47、ion management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring equipment Series P Telephone transmission quality, telephone installations, local line networks Series Q Switching and s
48、ignalling, and associated measurements and tests Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects, next-generation networks, Internet of Things and smart cities Series Z Languages and general software aspects for telecommunication systems
