Data-Over-Cable Service Interface Specifications DOCSIS 2.0 Radio Frequency Interface Specification CM-SP-RFIv2.0-I07-041210 ISSUED SPECIFICATION Notice This document is a cooperative effort undertaken at the direction of Cable Television Laboratories, Inc. for the benefit of the cable industry in general. Neither CableLabs nor any member company is responsible for any liability of any nature whatsoever resulting from or arising out of use or reliance upon this specification by any party. This document is furnished on an “AS IS” basis and neither CableLabs nor its members provides any representation or warranty, express or implied, regarding its accuracy, completeness, or fitness for a particular purpose. © Copyright 1999-2004 Cable Television Laboratories, Inc. All rights reserved. CM-SP-RFIv2.0-I07-041210 Data-Over-Cable Service Interface Specifications Document Status Sheet Document Control Number: CM-SP-RFIv2.0-I07-041210 Reference: Radio Frequency Interface Specification Revision History: I01 — First Issued Release, December 31, 2001 I02 — Second Issued Release, June 17, 2002 I03 — Third Issued Release, December 18, 2002 I04 — Fourth Issued Release, July 30, 2003 I05 — Fifth Issued Release, April 7, 2004 I06 — Sixth Issued Release, August 4, 2004 I07 — Seventh Issued Release, December 10, 2004 Date: December 10, 2004 Status Code: Work in Draft Issued Closed Process Distribution Restrictions: CableLabs CL CL Public only Reviewers Vendor Key to Document Status Codes Work in Process: An incomplete document, designed to guide discussion and generate feedback, that may include several alternative requirements for consideration. Draft: A document in specification format considered largely complete, but lacking review by cable industry and vendors. Drafts are susceptible to substantial change during the review process. Issued: A stable document, which has undergone rigorous member and vendor review and is suitable for product design and development, cross-vendor interoperability, and for certification testing. Closed: A static document, reviewed, tested, validated, and closed to further engineering change requests to the specification through CableLabs. Trademarks: DOCSIS®, eDOCSIS™, PacketCable™, CableHome®, OpenCable™, CableCARD™, CableOffice™ , and CableLabs® are trademarks of Cable Television Laboratories, Inc. ii Radio Frequency Interface Specification CM-SP-RFIv2.0-I07-041210 Table of Contents 1 SCOPE AND PURPOSE.................................................................................................................................1 1.1 SCOPE ................................................................................................................................................................1 1.2 REQUIREMENTS .................................................................................................................................................2 1.3 BACKGROUND ...................................................................................................................................................2 1.3.1 Service Goals..........................................................................................................................................2 1.3.2 Reference Architecture ...........................................................................................................................3 1.3.3 Categories of Interface Specification .....................................................................................................5 1.3.4 Statement of Compatibility .....................................................................................................................5 1.4 CONVENTIONS FOR THIS SPECIFICATION...........................................................................................................5 2 REFERENCES (NORMATIVE/INFORMATIVE) .....................................................................................7 3 GLOSSARY (INFORMATIVE) ..................................................................................................................11 4 FUNCTIONAL ASSUMPTIONS.................................................................................................................23 4.1 BROADBAND ACCESS NETWORK ....................................................................................................................23 4.2 EQUIPMENT ASSUMPTIONS..............................................................................................................................23 4.2.1 Frequency Plan.....................................................................................................................................23 4.2.2 Compatibility with Other Services........................................................................................................24 4.2.3 Fault Isolation Impact on Other Users.................................................................................................24 4.2.4 Cable System Terminal Devices ...........................................................................................................24 4.3 RF CHANNEL ASSUMPTIONS ...........................................................................................................................24 4.3.1 Transmission Downstream ...................................................................................................................24 4.3.2 Transmission Upstream........................................................................................................................25 4.4 TRANSMISSION LEVELS ...................................................................................................................................26 4.5 FREQUENCY INVERSION ..................................................................................................................................26 5 COMMUNICATION PROTOCOLS ..........................................................................................................27 5.1 PROTOCOL STACK ...........................................................................................................................................27 5.1.1 CM and CMTS as Hosts .......................................................................................................................27 5.1.2 Data Forwarding Through the CM and CMTS ....................................................................................28 5.2 THE MAC FORWARDER ..................................................................................................................................31 5.2.1 Rules for Data-Link-Layer Forwarding ...............................................................................................32 5.3 NETWORK LAYER............................................................................................................................................32 5.3.1 Requirements for IGMP Management..................................................................................................33 5.4 ABOVE THE NETWORK LAYER ........................................................................................................................35 5.5 DATA LINK LAYER..........................................................................................................................................35 5.5.1 LLC Sublayer........................................................................................................................................36 5.5.2 Link-Layer Security Sublayer ...............................................................................................................36 5.5.3 MAC Sublayer.......................................................................................................................................36 5.6 PHYSICAL LAYER ............................................................................................................................................36 5.6.1 Downstream Transmission Convergence Sublayer..............................................................................36 iii CM-SP-RFIv2.0-I07-041210 Data-Over-Cable Service Interface Specifications 5.6.2 PMD Sublayer...................................................................................................................................... 37 6 PHYSICAL MEDIA DEPENDENT SUBLAYER SPECIFICATION .................................................... 39 6.1 SCOPE ............................................................................................................................................................. 39 6.2 UPSTREAM ...................................................................................................................................................... 39 6.2.1 Overview .............................................................................................................................................. 39 6.2.2 Signal Processing Requirements ......................................................................................................... 40 6.2.3 Modulation Formats ............................................................................................................................ 44 6.2.4 R-S Encode........................................................................................................................................... 44 6.2.5 R-S Frame Structure 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