1、 ETSI TR 102 881 V1.1.1 (2010-06)Technical Report Access, Terminals, Transmission and Multiplexing (ATTM);Cable Network HandbookETSI ETSI TR 102 881 V1.1.1 (2010-06) 2Reference DTR/ATTM-003009 Keywords broadband, cable, IPCable ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.
2、: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-Prfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloaded from: http:/www.etsi.org The present document may be made a
3、vailable in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept o
4、n a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http:/portal.etsi.org/tb/status/status.asp If you fin
5、d errors in the present document, please send your comment to one of the following services: http:/portal.etsi.org/chaircor/ETSI_support.asp Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction
6、 in all media. European Telecommunications Standards Institute 2010. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTM, TIPHONTM, the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM is a Trade Mark of ETSI registered for the benefit of its Membe
7、rs and of the 3GPP Organizational Partners. LTE is a Trade Mark of ETSI currently being registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM and the GSM logo are Trade Marks registered and owned by the GSM Association. ETSI ETSI TR 102 881 V1.1.1 (2010-06) 3Contents
8、 Intellectual Property Rights 5g3Foreword . 5g3Introduction 5g31 Scope 6g32 References 6g32.1 Normative references . 6g32.2 Informative references 6g33 Symbols and abbreviations . 7g33.1 Symbols 7g33.2 Abbreviations . 7g34 Network of the Cable operator . 8g34.1 History of the CATV network 8g34.2 HFC
9、 Network . 10g34.2.1 Architecture 10g34.2.2 Components 11g34.2.3 Tree-and-branch topology . 11g34.2.4 Star topology . 12g34.3 Backbone network 14g34.4 Home network 15g34.4.1 Network Interface Unit . 15g34.4.2 Distribution of video signals . 15g34.4.3 Distribution of data signals . 15g34.4.4 Examples
10、 of poor in-home installations 15g35 Physical layer . 16g35.1 Radio-frequency carrier and spectrum . 16g35.1.1 Downstream frequencies . 17g35.1.2 Upstream frequencies . 17g35.2 Analogue transmission . 17g35.2.1 AM modulation . 17g35.2.2 FM modulation . 17g35.3 Digital transmission based on QAM modul
11、ation . 17g35.4 Noise and interference 18g35.4.1 Upstream noise and interference . 18g35.4.2 Downstream noise and interference 19g36 Services 19g36.1 Data services 19g36.1.1 EuroDOCSIS protocol 19g36.2 Telephony services . 20g36.2.1 Telephony over cable 20g36.2.2 IP telephony based on EuroPacketCabl
12、e 20g36.3 Audio and Video Services 21g36.3.1 Compression . 21g36.3.2 FM radio . 22g36.3.3 Broadcast TV 22g36.3.3.1 Cable television headend . 22g36.3.3.2 Analogue TV . 24g36.3.3.3 Digital TV based on DVB-C . 24g36.3.4 IPTV . 25g36.3.5 Interactive TV . 25g36.3.6 Video on Demand . 26g36.3.7 Encryption
13、 and conditional access 26g3ETSI ETSI TR 102 881 V1.1.1 (2010-06) 4Annex A: Bibliography 27g3History 28g3ETSI ETSI TR 102 881 V1.1.1 (2010-06) 5Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to t
14、hese essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found in ETSI SR 000 314: “Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards“, which is available from the ETSI Secretariat. Late
15、st updates are available on the ETSI Web server (http:/webapp.etsi.org/IPR/home.asp). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates
16、 on the ETSI Web server) which are, or may be, or may become, essential to the present document. Foreword This Technical Report (TR) has been produced by ETSI Technical Committee Access, Terminals, Transmission and Multiplexing (ATTM). Introduction The core expertise within ETSI responsible for Euro
17、pean Standards covering Integrated Broadband Cable and Television Networks (ATTM-AT3) has received requests from industry to produce a cable network handbook in order to assist decision makers, both technical and regulatory people. The current document is a cable handbook produced in cooperation wit
18、h Excentis and Cable Europe in order to provide the reader with a high level technical understanding of the CATV and Broadband Cable Networks. ETSI ETSI TR 102 881 V1.1.1 (2010-06) 61 Scope The present document is a technical report providing general overview of the Integrated Broadband Cable and Te
19、levision Networks and is intended as a handbook for engineers and non-engineers to familiarize themselves with the Cable Network infrastructure, architecture, components and protocols including high level description of its transmission principles 2 References References are either specific (identif
20、ied by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. Referenced documents which are not found to be p
21、ublicly available in the expected location might be found at http:/docbox.etsi.org/Reference. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity. 2.1 Normative references The following referenced documents are neces
22、sary for the application of the present document. Not applicable. 2.2 Informative references The following referenced documents are not necessary for the application of the present document but they assist the user with regard to a particular subject area. Not applicable. i.1 ETSI ES 201 488 (all pa
23、rts): “Access and Terminals (AT); Data Over Cable Systems“. NOTE: EuroDOCSIS 1.1 is ES 201 488 (parts 1, 2, 3). i.2 ISO/IEC 13818:“Information technology - Generic coding of moving pictures and associated audio information“. i.3 ETSI ES 202 488 (all parts): “Access and Terminals (AT); Second Generat
24、ion Transmission Systems for Interactive Cable Television Services - IP Cable Modems“. NOTE: EuroDOCSIS 2.0 is ES 202 488 (parts 1, 2, 3). i.4 ETSI TS 102 639 (all parts): “Access and Terminals, Transmission and Multiplexing (ATTM); Third Generation Transmission Systems for Interactive Cable Televis
25、ion Services - IP Cable Modems“. NOTE: EuroDOCSIS 3.0 is TS 102 639 (parts 1, 2, 3, 4, 5). i.5 ETSI TS 101 909-4: “Digital Broadband Cable Access to the Public Telecommunications Network; IP Multimedia Time Critical Services; Part 4: Network Call Signalling Protocol Partial Endorsement of ITU-T Reco
26、mmendation J.162 (11/2005), modified“. i.6 ISO/IEC 14496-10: “Information technology - Coding of audio-visual objects - Part 10: Advanced Video Coding“. ETSI ETSI TR 102 881 V1.1.1 (2010-06) 73 Symbols and abbreviations 3.1 Symbols For the purposes of the present document, the following symbols the
27、following apply: Gbps Gigabit per second GHz GigaHertz kbps kilobit per second kHz kiloHertz MHz MegaHertz 3.2 Abbreviations For the purposes of the present document, the following abbreviations apply: AM Amplitude Modulation ANC Announcement ControllerANP Announcement Player ANS Announcement Server
28、 AS Authorization Server ATV Analogue TeleVisionCA Call Agent or Conditional Access CATV Cable TeleVision / Community Antenna TeleVision CM Cable Modem CMS Call Management Server CMTS Cable Modem Termination System CPE Customer Premise Equipment CSA Common Scrambling AlgorithmDC District Center DHCP
29、 Dynamic Host Configuration Protocol DNS Domain Name Server DOCSIS Data Over Cable Service Interface Specification DS DownStream DTV Digital TeleVision DVB Digital Video Broadcasting ETSI European Telecommunications Standardisation Institute EuroDOCSIS European Data over Cable System Interface Speci
30、fication FA Final Amplifier FDM Frequency Domain Multiplexing FDMA Frequency Division Multiple Access FM Frequency Modulation GA Group Amplifier GC Gate Controller HDTV High-Definition Television HE HeadEnd HFC Hybrid Fibre Coax HTTP HyperText Transfer Protocol IP Internet Protocol IPTV IP Televisio
31、n ISO International Standardisation Organisation KDC Key Distribution Center LC Local Center MAC Media Access Control Mbps Megabit per second MG Media Gateway MGC Media Gateway Controller MPEG Moving Pictures Expert Group MPLS Multi Protocol Label Switching ETSI ETSI TR 102 881 V1.1.1 (2010-06) 8MTA
32、 Multimedia Terminal Adapter MTP Multi-TaP MUX Multiplexing NIU Network Interface Unit NOC Network Operating Center NTU Network Termination Unit ON Optical Node OSS Operating Support System PAL Phase Alternating LinePSI Program Specific Information PSTN Public Switched Telephone Network QAM Quadratu
33、re Amplitude Modulation QoS Quality of Service RC Regional CenterRF RadioFrequency SDH Synchronous Digital Hierarchy SDTV Standard-definition TelevisionSECAM SEquentiel Couleur A Mmoire SG Signalling Gateway SI Service Information SONET Synchronous Optical NETwork SS7 Signalling System 7 STB Set-Top
34、 Box TDMA Time Division Multiple Access TFTP Trivial File Transfer Protocol TGS Ticket Granting Server ToIP Telephony over IP US UpStream UTP Unshielded Twisted Pair VoD Video on Demand 4 Network of the Cable operator 4.1 History of the CATV network The CATV (Community Antenna TeleVision) network wa
35、s originally set up to deliver one-way, analogue broadcast TV transmission (unidirectional from headend to subscriber) services (Figure 1). A headend (HE) has in the cable network operators terminology two meanings: the first one refers to the equipment for receiving television signals for processin
36、g and distribution over a cable television system, the second one describes facilities in which the equipment is installed that converts the received signals into ones that are distributed in the CATV or HFC (see clause 4.2) network. ETSI ETSI TR 102 881 V1.1.1 (2010-06) 9Figure 1: The CATV network
37、(HE=headend) Signals were captured using terrestrial and satellite antennas and distributed using a coaxial network within the local community. The earliest deployments started in the thirties. Until the nineties, there were thousands of small networks all over Europe most of these are now consolida
38、ted into larger cable operators. Amplifiers are used to compensate for the attenuation of the coaxial cables. Although the attenuation for two types of cable for in-home use is depicted in Figure 2, it shows the general frequency-dependent trend of the attenuation of coaxial cables. This frequency d
39、ependency is normally compensated for by equalisation filters in the amplifiers. However the length of the cables between the amplifiers may not be too long in order that the input signal at the amplifier is above the noise level. This shows that extending the frequency spectrum above 1 GHz would ne
40、cessitate the reduction of the distance between the amplifiers which would require a complete re-implementation of the CATV/HFC network. This brings us to the conclusion that the frequency spectrum of the CATV and HFC network is limited at present to below 1 GHz. The amplifiers and tap values were c
41、hosen such that each house gets an equal TV signal. A huge number of houses (e.g. between 50 000 and 1,6 million) can be served by one headend. ETSI ETSI TR 102 881 V1.1.1 (2010-06) 10Figure 2: Frequency dependence of the attenuation of two types of coaxial cables Since the end of the nineties, most
42、 of the CATV networks have been converted for bi-directional operation into a Hybrid Fibre Coax (HFC) architecture. 4.2 HFC Network 4.2.1 Architecture Hybrid Fibre Coax (HFC) access networks are composed of optical fibre and coaxial cables (Figure 3). Typically, optical fibre rings radiate from the
43、regional headend to optical nodes where the signals are transferred to coaxial cables and then carried to the customer location. A headend may serve many tens of thousands of customer premises, with substantial resilience in the access network resulting in the need for network power at many roadside
44、 locations. Optical nodes typically serve between several hundred to some thousands of homes. g3HE 1Residential CustomerOptical Node 1ON nON 2Fiber Ring BroadbandBidirectionalamplifierCM NIUCoax partFiber partFigure 3: HFC network g30510152025300 200 400 600 800 1000 1200Frequency MHzAttenuation dB/
45、100mRG-59RG-6ETSI ETSI TR 102 881 V1.1.1 (2010-06) 114.2.2 Components If we have a closer look at the HFC network from the optical node to the home, we can distinguish different components (see Figure 5). Two optical fibres arrive in the optical node (in practice 4 for redundancy reasons), one with
46、the upstream signal and one with the downstream signal. In the fibres, digital and analogue information is transmitted over the optical fibre through modulation of a sine carrier. Simply said, light is sent all the time and it is the fluctuation of the light that tells the receiver what information
47、the sender is transmitting. In the optical node two conversions are executed: the optical signal is converted to an electrical signal by a photodetector (o/e conversion) and the diplex filter only puts the downstream signal on the coaxial cable; the upstream signal on the coaxial input of the optica
48、l node is also filtered by the other part of the diplex filter and is sent as input to the laser (electrical to optical - e/o conversion) to modulate the light signal in the upstream fibre. Behind the optical node towards the homes, the coaxial distribution plant delivers all downstream signals to t
49、he homes and transports the upstream signals coming from the homes back to the optical node. Individual components are shown in Figure 4. g3Coaxial cabl eSplitter AmplifierFibreTapFigure 4: HFC network components Two topologies for the coaxial part of the HFC network are in use in Europe: the tree-and-branch and the star architecture. 4.2.3 Tree-and-branch topology Tree-and-branch is the most typical architecture for the coaxial distribution plant (Figure 5). The main trunk cable is split in branches though splitters. Splitters are bi-directional passive
