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Cable Network Handbook CEL-TR-HFC-HANDBOOK-V4_3-091001 Technical Report Cable Network Handbook; Overview of Architecture, Technical Features and Services of Integrated Broadband and Cable TV Networks CEL-TR-HFC-HANDBOOK-V4_3-091001 2 Cable Network Handbook Keywords Cable Network, HFC Network, Television, Broadband Services Cable Europe Labs Cable House Avenue des Arts 41 B – 1040 Brussels BELGIUM Tel.: +32 2 521 17 63 Fax: +32 2 521 79 76 Important notice This technical report is the result of a cooperative effort undertaken at the direction of Cable Europe Labs for the benefit of the cable industry and its customers. This document may contain references to other documents not owned or controlled by Cable Europe Labs. Use and understanding of this document may require access to such other documents. Designing, manufacturing, distributing, using, selling, or servicing products, or providing services, based on this document may require intellectual property licenses from third parties for technology referenced in this document. Neither Cable Europe Labs nor any member company is responsible to any party for any liability of any nature whatsoever resulting from or arising out of use or reliance upon this document, or any document referenced herein. This document is furnished on an "AS IS" basis and neither Cable Europe Labs nor its members provides any representation or warranty, express or implied, regarding the accuracy, completeness, noninfringement, or fitness for a particular purpose of this document, or any document referenced herein. Individual copies of the present document can be downloaded from: http://www.cable-europe.eu/labs The present document may be made available 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) as maintained by the secretariat of Cable Europe Labs. Users of the present document should be aware that the document may be subject to revision or change of status. If you find errors in the present document, please send your comment to the following services: [email protected] Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © Cable Europe 2009. All rights reserved. © Cable Europe Cable Network Handbook 3 CEL-TR-HFC-HANDBOOK-V4_3-091001 Contents 1 Scope........................................................................................................................................................4 2 References................................................................................................................................................4 2.1 Reference acquisition......................................................................................................................................... 4 3 Definitions, symbols and abbreviations ...................................................................................................5 3.1 Abbreviations..................................................................................................................................................... 5 4 Network of the Cable Operator ................................................................................................................7 4.1 History of the CATV Network .......................................................................................................................... 7 4.2 HFC Network..................................................................................................................................................... 8 4.2.1 Architecture.................................................................................................................................................. 8 4.2.2 Components ................................................................................................................................................. 9 4.2.3 Network Topology ....................................................................................................................................... 9 4.2.3.1 Tree-and-branch topology.................................................................................................................... 10 4.2.3.2 Star topology ........................................................................................................................................ 10 4.3 Backbone Network .......................................................................................................................................... 12 4.4 Home Network................................................................................................................................................. 13 4.4.1 Network Interface Unit .............................................................................................................................. 13 4.4.2 Distribution of Video Signals..................................................................................................................... 13 4.4.3 Distribution of Data Signals....................................................................................................................... 14 4.4.4 Examples of Poor In-home Installations .................................................................................................... 14 5 Physical Layer........................................................................................................................................14 5.1 Radiofrequency Carrier and Spectrum............................................................................................................. 14 5.1.1 Downstream Frequencies ........................................................................................................................... 15 5.1.2 Upstream Frequencies................................................................................................................................ 15 5.2 Analogue Transmission ................................................................................................................................... 15 5.2.1 Amplitude Modulation............................................................................................................................... 15 5.2.2 Frequency Modulation ............................................................................................................................... 15 5.3 Digital Transmission based on QAM .............................................................................................................. 16 5.4 Noise and Interference..................................................................................................................................... 16 5.4.1 Upstream Noise and Interference............................................................................................................... 16 5.4.2 Downstream Noise and Interference .......................................................................................................... 17 6 Services ..................................................................................................................................................18 6.1 Data Services ................................................................................................................................................... 18 6.1.1 EuroDOCSIS Protocol ............................................................................................................................... 18 6.2 Telephony Services.......................................................................................................................................... 18 6.2.1 Telephony over Cable ................................................................................................................................ 18 6.2.2 Voice over IP based on EuroPacketCable.................................................................................................. 19 6.3 Audio and Video Services ............................................................................................................................... 20 6.3.1 Compression............................................................................................................................................... 20 6.3.2 FM Radio................................................................................................................................................... 21 6.3.3 Broadcast TV ............................................................................................................................................. 22 6.3.3.1 Cable Television Headend.................................................................................................................... 22 6.3.3.2 Analogue TV........................................................................................................................................ 23 6.3.3.3 Digital TV based on DVB-C ................................................................................................................ 24 6.3.4 IPTV........................................................................................................................................................... 25 6.3.5 Interactive TV ............................................................................................................................................ 25 6.3.6 Video
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