ETSI ES V1.2.2 ( )

Transcription

1 ES V1.2.2 ( ) Standard Access and Terminals (AT); Data Over Cable Systems; Part 2: Radio Frequency Interface Specification

2 2 ES V1.2.2 ( ) Reference RES/AT Keywords access, broadband, broadcasting, cable, data, IPCable, modem 650 Route des Lucioles F Sophia Antipolis Cedex - FRANCE Tel.: Fax: Siret N NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloaded from: 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). In case of dispute, the reference shall be the printing on printers of the PDF version kept on a specific network drive within 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 documents is available at If you find errors in the present document, send your comment to: editor@etsi.org 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. European Telecommunications Standards Institute All rights reserved. DECT TM, PLUGTESTS TM and UMTS TM are Trade Marks of registered for the benefit of its Members. TIPHON TM and the TIPHON logo are Trade Marks currently being registered by for the benefit of its Members. 3GPP TM is a Trade Mark of registered for the benefit of its Members and of the 3GPP Organizational Partners.

3 3 ES V1.2.2 ( ) Contents Intellectual Property Rights...15 Foreword Scope General scope Requirements Background Service goals Reference architecture Categories of interface specification Data Over Cable service interface documents Statement of compatibility References Definitions and abbreviations Definitions Abbreviations Functional assumptions Broadband access network Equipment assumptions Frequency plan Compatibility with other services Fault isolation impact on other users Cable system terminal devices RF channel assumptions Transmission downstream Transmission upstream Availability Transmission levels Frequency inversion Communication protocols Protocol stack CM and CMTS as hosts Data forwarding through the CM and CMTS General CMTS forwarding rules CM forwarding rules CPE MAC address acquisition Forwarding The MAC forwarder Rules for data-link-layer forwarding Network layer Requirements for IGMP management IGMP timer requirements CMTS rules CM rules Above the network layer Data Link Layer (DLL) LLC sublayer Link-layer security sublayer MAC sublayer MAC service definition Physical layer Downstream transmission convergence sublayer PMD sublayer...42

4 4 ES V1.2.2 ( ) Interface points Physical Media Dependent sublayer specification Scope Upstream Overview Modulation formats Modulation rates Symbol mapping Spectral shaping Upstream frequency agility and range Spectrum format FEC encode FEC encode modes FEC bit-to-symbol ordering Scrambler (randomizer) Preamble prepend Transmit pre-equalizer Burst profiles Burst timing convention Transmit power requirements Output power agility and range Fidelity requirements Spurious emissions Adjacent channel spurious emissions Spurious emissions in 5 MHz to 42 MHz Spurious emissions during burst On/Off transients Symbol Error Rate (SER) Filter distortion Amplitude Phase Carrier phase noise Channel frequency accuracy Symbol rate accuracy Symbol timing jitter Frame structure Codeword length Fixed codeword length Shortened last codeword Signal processing requirements Upstream demodulator input power characteristics Upstream electrical output from the CM Downstream Downstream protocol Scalable interleaving to support low latency Downstream frequency plan CMTS output electrical Downstream electrical input to CM CM BER performance QAM QAM CM BER performance QAM image rejection performance QAM adjacent channel performance QAM QAM CM BER performance QAM image rejection performance QAM adjacent channel performance CMTS timestamp jitter Downstream transmission convergence sublayer Introduction MPEG packet format...64

5 5 ES V1.2.2 ( ) 7.3 MPEG header for DOCS Data Over Cable MPEG payload for DOCS Data Over Cable Interaction with the MAC sublayer Interaction with the physical Layer MPEG header synchronization and recovery Media Access Control (MAC) specification Introduction Overview Definitions MAC-sublayer domain MAC Service Access Point (MSAP) Service flows Upstream intervals, mini-slots and 6,25-µs increments Frame Future use MAC frame formats Generic MAC frame format PMD overhead MAC frame transport Ordering of bits and octets Representing negative numbers Type/Length/Value fields MAC header format Data PDU Packet-based MAC frames Variable-length packets ATM Cell MAC Frames Reserved PDU MAC Frames MAC-specific headers Timing header MAC management header Request frame Fragmentation header Concatenation header Extended MAC headers Piggyback requests Fragmentation extended header Service flow extended header Payload Header Suppression (PHS) header Unsolicited grant synchronization header Fragmented MAC frames Considerations for concatenated packets and fragmentation Error-handling Error recovery during fragmentation Error codes and messages MAC management messages MAC management message header Time Synchronization (SYNC) Upstream Channel Descriptor (UCD) Example of UCD encoded TLV data Upstream bandwidth allocation Map (MAP) Ranging - Request (RNG-REQ) Ranging - Response (RNG-RSP) Encodings Example of TLV data Overriding channels prior to registration Registration - Request (REG-REQ) Registration - Response (REG-RSP) Encodings Modem capabilities DOCS 1.0 service class data...100

6 6 ES V1.2.2 ( ) Registration - Acknowledge (REG-ACK) Upstream Channel Change - Request (UCC-REQ) Encodings Ranging technique Upstream Channel Change - Response (UCC-RSP) Dynamic Service Addition - Request (DSA-REQ) CM-initiated Dynamic Service Addition CMTS-initiated Dynamic Service Addition Dynamic Service Addition - Response (DSA-RSP) CM-initiated Dynamic Service Addition CMTS-initiated Dynamic Service Addition Dynamic Service Addition - Acknowledge (DSA-ACK) Dynamic Service Change - Request (DSC-REQ) Dynamic Service Change - Response (DSC-RSP) Dynamic Service Change - Acknowledge (DSC-ACK) Dynamic Service Deletion - Request (DSD-REQ) Dynamic Service Deletion - Response (DSD-RSP) Dynamic Channel Change - Request (DCC-REQ) Encodings Upstream Channel ID Downstream parameters Initialization technique UCD substitution Security Association IDentifier (SAID) substitution Service flow substitutions CMTS MAC address Dynamic Channel Change - Response (DCC-RSP) Encodings CM jump time Dynamic Channel Change - Acknowledge (DCC-ACK) Device Class Identification - Request (DCI-REQ) Device Class Identification - Response (DCI-RSP) UPstream transmitter DISable (UP-DIS) MAC management message Media Access Control (MAC) protocol operation Upstream bandwidth allocation Allocation MAP MAC management message Information Elements (IE) Request IE Request/Data IE Initial maintenance IE Station maintenance IE Short and long data grant IEs Data acknowledge IE Expansion IE Null IE Requests Information Element feature usage summary Map transmission and timing Protocol example Support for multiple channels Timing and synchronization Global timing reference CM channel acquisition Ranging Timing units and relationships Upstream transmission and contention resolution Contention resolution overview Transmit opportunities M bandwidth utilization Data link encryption support MAC messages...134

7 7 ES V1.2.2 ( ) Framing Quality of Service and fragmentation Theory of operation Concepts Service Flows Classifiers Object model Service classes Authorization Types of service flows Provisioned service flows Admitted service flows Active service flows Service flows and classifiers Policy-based classification and service classes General operation Static operation Dynamic service flow creation - CM initiated Dynamic service flow creation - CMTS initiated Dynamic service flow modification and deletion Upstream service flow scheduling services Unsolicited Grant Service (UGS) Real-time Polling Service (rtps) Unsolicited Grant Service with Activity Detection (UGS/AD) Non-real-time Polling Service (nrtps) Best Effort service Other services Committed Information Rate (CIR) Parameter applicability for upstream service scheduling CM transmit behaviour Fragmentation CM fragmentation support Fragmentation rules CMTS fragmentation support Multiple grant mode Piggyback mode Fragmentation example Single packet fragmentation Concatenated packet fragmentation Payload Header Suppression (PHS) Overview Example applications Operation Signalling Payload Header Suppression examples Upstream example Downstream example Cable Modem - CMTS interaction CMTS initialization Cable Modem Initialization Scanning and synchronization to downstream Obtain upstream parameters Message Flows during scanning and upstream parameter acquisition Ranging and automatic adjustments Ranging parameter adjustment Device class identification Establish IP connectivity Establish time of day Transfer operational parameters Registration...175

8 8 ES V1.2.2 ( ) Baseline privacy initialization Service IDs during CM initialization Multiple-channel support Standard operation Periodic signal level adjustment Changing upstream burst parameters Changing upstream channels Dynamic service Dynamic service flow state transitions Dynamic Service Addition (DSA) CM initiated Dynamic Service Addition CMTS initiated Dynamic Service Addition Dynamic Service Addition state transition diagrams Dynamic Service Change (DSC) CM-initiated Dynamic Service Change CMTS-initiated Dynamic Service Change Dynamic Service Change state transition diagrams Dynamic Service Deletion (DSD) CM initiated Dynamic Service Deletion CMTS initiated Dynamic Service Deletion Dynamic Service Deletion state transition diagrams Dynamically changing downstream and/or upstream channels DCC general operation Derivation of T15 timer DCC exception conditions DCC performance Near-seamless channel change Example operation Example signalling Example timing Fault detection and recovery Prevention of unauthorized transmissions Supporting future new cable modem capabilities Downloading cable modem operating software Annex A (normative): Well-known addresses A.1 MAC addresses A.2 MAC service IDs A.2.1 All CMs and no CM service IDs A.2.2 Well-known "Multicast" service IDs A.2.3 Priority request service IDs A.3 MPEG PID Annex B (normative): Parameters and constants Annex C (normative): Common Radio Frequency interface encodings C.1 Encodings for configuration and MAC-layer messaging C.1.1 Configuration file and registration settings C Downstream frequency configuration setting C Upstream channel ID configuration setting C Network access control object C DOCS 1.0 Class of service configuration setting C Class ID C Maximum downstream rate configuration setting C Maximum upstream rate configuration setting C Upstream channel priority configuration setting C Guaranteed minimum upstream channel data rate configuration setting C Maximum upstream channel transmit burst configuration setting C Class-of-service privacy enable...247

9 9 ES V1.2.2 ( ) C CM Message Integrity Check (MIC) configuration setting C CMTS Message Integrity Check (MIC) configuration setting C Maximum number of CPEs C TFTP server timestamp C TFTP server provisioned modem address C Upstream packet classification configuration setting C Downstream packet classification configuration setting C Upstream service flow encodings C Downstream service flow encodings C Payload Header Suppression (PHS) C Maximum number of classifiers C Privacy enable C Vendor-specific information C Subscriber management TLVs C Subscriber management control C Subscriber management CPE IP table C Subscriber management filter groups C.1.2 Configuration-file-specific settings C End-of-data marker C Pad configuration setting C Software upgrade filename C SNMP write-access control C SNMP MIB object C CPE Ethernet MAC address C Software upgrade TFTP server C SnmpV3 kickstart value C SnmpV3 kickstart security name C SnmpV3 kickstart manager public number C Manufacturer code verification certificate C Co-signer code verification certificate C SNMPv3 notification receiver C SNMPv3 notification receiver IP address C SNMPv3 notification receiver UDP port number C SNMPv3 notification receiver trap type C SNMPv3 notification receiver timeout C SNMPv3 notification receiver retries C Notification receiver filtering parameters C Notification receiver security name C.1.3 Registration-Request/Response-specific encodings C Modem capabilities encoding C Concatenation support C DOCS version C Fragmentation support C Payload Header Suppression support C IGMP support C Privacy support C Downstream SAID support C Upstream SID support C Optional filtering support C Transmit equalizer taps per symbol C Number of transmit equalizer taps C DCC support C Vendor ID encoding C Modem IP address C Service(s) not available response C.1.4 Dynamic-Service-Message-specific encodings C HMAC-digest C Authorization block C Key sequence number C.2 Quality of Service-related encodings C.2.1 Packet classification encodings...260

10 10 ES V1.2.2 ( ) C Upstream packet classification encoding C Downstream packet classification encoding C General packet classifier encodings C Classifier reference C Classifier identifier C Service flow reference C Service flow Identifier C Rule priority C Classifier activation state C Dynamic service change action C Classifier error encodings C Errored parameter C Error code C Error message C IP packet classification encodings C IP type of service range and mask C IP protocol C IP source address C IP source mask C IP destination address C IP destination mask C TCP/UDP source port start C TCP/UDP source port end C TCP/UDP destination port start C TCP/UDP destination port end C Ethernet LLC packet classification encodings C Destination MAC address C Source MAC address C Ethertype/DSAP/MacType C IEEE 802.1P/Q packet classification encodings C IEEE 802.1P User_Priority C IEEE 802.1Q VLAN_ID C Vendor specific classifier parameters C.2.2 Service flow encodings C Upstream service flow encodings C Downstream service flow encodings C General service flow encodings C Service flow reference C Service Flow IDentifier (SFID) C Service identifier C Service class name C Quality of Service parameter set type C Service flow error encodings C Errored parameter C Error code C Error message C Common upstream and downstream Quality of Service parameter encodings C Traffic priority C Maximum sustained traffic rate C Upstream maximum sustained traffic rate C Downstream maximum sustained traffic rate C Maximum traffic burst C Minimum reserved traffic rate C Assumed minimum reserved rate packet size C Timeout for active QoS parameters C Timeout for admitted QoS parameters C Vendor specific QoS parameters C Upstream-Specific QoS parameter encodings C Maximum concatenated burst C Service flow scheduling type C Request/Transmission policy C Nominal polling interval...275

11 11 ES V1.2.2 ( ) C Tolerated poll jitter C Unsolicited grant size C Nominal grant interval C Tolerated grant jitter C Grants per interval C IP type of service overwrite C Unsolicited grant time reference C Downstream-Specific QoS parameter encodings C Maximum downstream latency C Payload Header Suppression (PHS) C Classifier reference C Classifier identifier C Service flow reference C Service Flow IDentifier (SFID) C Dynamic service change action C Payload Header Suppression error encodings C Errored parameter C Error code C Error message C Payload Header Suppression rule encodings C Payload Header Suppression Field (PHSF) C Payload Header Suppression Index (PHSI) C Payload Header Suppression Mask (PHSM) C Payload Header Suppression Size (PHSS) C Payload Header Suppression Verification (PHSV) C Vendor specific PHS parameters C.3 Encodings for other interfaces C.3.1 Telephone settings option C.3.2 Baseline privacy configuration settings option C.4 Confirmation Code (CC) C.4.1 Confirmation Codes for Dynamic Channel Change C.4.2 Confirmation Codes for major errors Annex D (normative): CM configuration interface specification D.1 CM IP addressing D.1.1 DHCP fields used by the CM D.2 CM configuration D.2.1 CM binary configuration file format D.2.2 Configuration file settings D.2.3 Configuration file creation D CM MIC calculation D.3 Configuration verification D.3.1 CMTS MIC calculation D Digest calculation Annex E (informative): MAC service definition E.1 MAC service overview E.1.1 MAC service parameters E.2 MAC data service interface E.2.1 MAC_DATA.request E.2.2 MAC_DATA.indicate E.2.3 MAC_GRANT_SYNCHRONIZE.indicate E.2.4 MAC_CMTS_MASTER_CLOCK_SYNCHRONIZE.indicate E.3 MAC control service interface E.3.1 MAC_REGISTRATION_RESPONSE.indicate E.3.2 MAC_CREATE_SERVICE_FLOW.request E.3.3 MAC_CREATE_SERVICE_FLOW.response...297

12 12 ES V1.2.2 ( ) E.3.4 MAC_CREATE_SERVICE_FLOW.indicate E.3.5 MAC_DELETE_SERVICE_FLOW.request E.3.6 MAC_DELETE_SERVICE_FLOW.response E.3.7 MAC_DELETE_SERVICE_FLOW.indicate E.3.8 MAC_CHANGE_SERVICE_FLOW.request E.3.9 MAC_CHANGE_SERVICE_FLOW.response E.3.10 MAC_CHANGE_SERVICE_FLOW.indicate E.4 MAC service usage scenarios E.4.1 Transmission of PDUs from upper layer service to MAC data service E.4.2 Reception of PDUs to upper layer service from MAC data service E.4.3 Sample sequence of MAC control and MAC data services Annex F (informative): Example preamble sequence F.1 Introduction F.2 Example preamble sequence Annex G (normative): DOCS v1.0/v1.1 interoperability G.1 Introduction G.2 General interoperability issues G.2.1 Provisioning G.2.2 Registration G.2.3 Dynamic service establishment G.2.4 Fragmentation G.2.5 Multicast support G.2.6 Upstream Channel Change (UCC) G.3 Hybrid devices G.4 Interoperability and performance Annex H (informative): Multiple upstream channels H.1 Single downstream and single upstream per cable segment H.2 Multiple downstreams and multiple upstreams per cable segment H.2.1 Topologies H.2.2 Normal operation H.2.3 Initial maintenance H.2.4 Dynamic Channel Change (DCC) Annex I (normative): The data over cable spanning tree protocol I.1 Background I.2 Public spanning tree I.3 Public spanning tree protocol details I.4 Spanning tree parameters and defaults Annex J (normative): Error codes and messages Annex K (informative): DOCS transmission and contention resolution K.1 Introduction Annex L (normative): IGMP example Annex M (normative): Unsolicited Grant Services (UGS) M.1 Unsolicited Grant Service (UGS) M.1.1 Introduction M.1.2 Configuration parameters...323

13 13 ES V1.2.2 ( ) M.1.3 Operation M.1.4 Jitter M.1.5 Synchronization issues M.2 Unsolicited Grant Service with Activity Detection (UGS-AD) M.2.1 Introduction M.2.2 MAC configuration parameters M.2.3 Operation M.2.4 Example M.2.5 Talk spurt grant burst M.2.6 Admission considerations Annex N (normative): European specification additions N.1 Scope and purpose N.2 References N.3 Definitions and abbreviations N.4 Functional assumptions N.4.1 Broadband access network N.4.2 Equipment assumptions N Frequency plan N Compatibility with other services N Fault isolation impact on other users N Cable system terminal devices N.4.3 RF channel assumption N Transmission downstream N Transmission upstream N Availability N.4.4 Transmission levels N.4.5 Frequency inversion N.5 Communication protocols N.6 Physical Media Dependent sublayer specification N.6.1 Scope N.6.2 Upstream N Overview N Modulation formats N Modulation rates N Symbol mapping N Spectral shaping N Upstream frequency agility and range N Spectrum format N FEC encode N FEC encode modes N FEC Bit-to-symbol ordering N Scrambler (randomizer) N Preamble prepend N Transmit pre-equalizer N Burst profiles N Burst timing convention N Transmit power requirements N Output power agility and range N Fidelity requirements N Spurious emissions N Adjacent channel spurious emissions N Spurious emissions in 5 MHz to 65 MHz N Spurious emissions during burst On/Off transients N Symbol Error Rate (SER) N Filter distortion N Amplitude...345

14 14 ES V1.2.2 ( ) N Phase N Carrier phase noise N Channel frequency accuracy N Symbol rate accuracy N Symbol timing jitter N Frame structure N Codeword length N Fixed codeword length N Shortened last codeword N Signal processing requirements N Upstream demodulator input power characteristics N Upstream electrical output from the CM N.6.3 Downstream N Downstream protocol N Interleaving N Downstream frequency plan N CMTS output electrical N Downstream electrical input to CM N CM BER performance N QAM N QAM CM BER performance N QAM image rejection performance N QAM Adjacent channel performance N QAM N QAM CM BER performance N QAM image rejection performance N QAM adjacent channel performance N Additional specifications for QAM N CMTS timestamp jitter N.7 Downstream transmission convergence sublayer N.7.1 Introduction N.7.2 MPEG packet format N.7.3 MPEG header for EuroDOCSIS Data Over Cable N.7.4 MPEG payload for EuroDOCSIS Data Over Cable N.7.5 Interaction with the MAC sublayer N.7.6 Interaction with the Physical layer N.7.7 MPEG header synchronization and recovery Annex O (informative): Bibliography History...357

15 15 ES V1.2.2 ( ) Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to. The information pertaining to these essential IPRs, if any, is publicly available for members and non-members, and can be found in SR : "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to in respect of standards", which is available from the Secretariat. Latest updates are available on the Web server ( Pursuant to the IPR Policy, no investigation, including IPR searches, has been carried out by. No guarantee can be given as to the existence of other IPRs not referenced in SR (or the updates on the Web server) which are, or may be, or may become, essential to the present document. Foreword This Standard (ES) has been produced by Technical Committee Access and Terminals (AT). NOTE: An earlier version of the present document was produced by JTC Broadcast. The present document is part 2 of a multi-part deliverable covering Data Over Cable Systems, as identified below: Part 1: Part 2: Part 3: "General"; "Radio Frequency Interface Specification"; "Baseline Privacy Plus Interface Specification".

16 16 ES V1.2.2 ( ) 1 Scope 1.1 General scope The present document defines the radio-frequency interface specifications for high-speed Data Over Cable Systems. They were developed for the benefit of the cable industry, including contributions by operators and vendors from North America, Europe, and other regions. The source material was the DOCSIS "Data Over Cable Services Interface Specifications, Radio Frequency Interface Specification 1.1 Interim 08 01/05/02", for which the latest published version can be found at There are differences in the cable spectrum planning practices adopted for different networks in the world. Therefore two options for physical layer technology are included, which have equal priority and are not required to be inter-operable. One technology option is based on the downstream multi-programme television distribution that is deployed in North America using 6 MHz channelling, and supports upstream transmission in the region 5 MHz to 42 MHz. The other technology option is based on the corresponding European multi-programme television distribution and supports upstream in the region 5 MHz to 65 MHz. Although both options have the same status, the first option was documented earlier and the second option introduced at a later time as an amendment, resulting in the document structure not reflecting this equal priority. The first of these options is defined in clauses 4, 6, 7, C and annex G, whereas the second is defined by replacing the content of those clauses with the content of annex N. Correspondingly, [33] and [36] apply only to the first option, and [9] only to the second. Compliance with the present document requires compliance with one or other of these implementations, not with both. It is not required that equipment built to one option shall inter-operate with equipment built to the other. These optional physical layer technologies allow operators some flexibility within any frequency planning, EMC and safety requirements that are mandated for their area of operation. For example, the 6 MHz downstream-based option defined by clauses 4, 6, and 7 might be deployable within an 8 MHz channel plan. Compliance with frequency planning and EMC requirements are not covered by the present document and remain the operators' responsibility. In this respect, [18], [19], and [8] are relevant to North America and [10], [11], [13], [14] and [15] are relevant to the European Community. The option of clauses 4, 6 and 7 together with clause C and annex G is required to be backwards compatible with an earlier version of that technology [6], whereas the option of annex N was not included in [6] and therefore is not required to be backwards compatible with [6]. Any reference in the present document to the transmission of television in the forward channel that is not consistent with [9] is outside the normative scope as only [9] is used for digital multi-program TV distribution by cable in European applications. Requirements for safety are outside the scope of the present document. Safety standards for European applications are published by CENELEC. NOTE 1: Examples of such CENELEC product safety standards are [16] and [12]. NOTE 2: For CENELEC safety categories of interfaces, see [7].

17 17 ES V1.2.2 ( ) 1.2 Requirements Throughout the present document, the words that are used to define the significance of particular requirements are capitalized. These words are: "MUST" "MUST NOT" "SHOULD" "SHOULD NOT" "MAY" This word or the adjective "REQUIRED" means that the item is an absolute requirement of the present document. This phrase means that the item is an absolute prohibition of the present document. This word or the adjective "RECOMMENDED" means that there may exist valid reasons in particular circumstances to ignore this item, but the full implications should be understood and the case carefully weighed before choosing a different course. This phrase means that there may exist valid reasons in particular circumstances when the listed behaviour is acceptable or even useful, but the full implications should be understood and the case carefully weighed before implementing any behaviour described with this label. This word or the adjective "OPTIONAL" means that this item is truly optional. One vendor may choose to include the item because a particular marketplace requires it or because it enhances the product, for example; another vendor may omit the same item. Other text is descriptive or explanatory. 1.3 Background Service goals Cable operators are interested in deploying high-speed packet-based communications systems on cable television systems that are capable of supporting a wide variety of services. Services under consideration by cable operators include packet telephony service, video conferencing service, T1/frame relay equivalent service, and many others. To this end, a series of interface specifications have been prepared that permit the early definition, design, development and deployment of Data Over Cable Systems on a uniform, consistent, open, non-proprietary, multi-vendor interoperable basis. The intended service will allow transparent bi-directional transfer of Internet Protocol (IP) traffic, between the cable system headend and customer locations, over an all-coaxial or Hybrid-Fibre/Coax (HFC) cable network. This is shown in simplified form in figure 1.1. Wide-Area Network CMTS Network Side Interface Cable Modem Termination System CMTS Cable Network Cable Modem (CM) Transparent IP Traffic Through the System CM Customer Premises Equipment Interface Customer Premises Equipment Figure 1.1: Transparent IP Traffic through the Data Over Cable System The transmission path over the cable system is realized at the headend by a Cable Modem Termination System (CMTS), and at each customer location by a Cable Modem (CM). At the headend (or hub), the interface to the Data Over Cable System is called the Cable Modem Termination System - Network Side Interface (CMTS-NSI) and is specified in [3]. At the customer locations, the interface is called the cable-modem-to-customer-premises-equipment interface (CMCI) and is specified in [4]. The intent is for operators to transparently transfer IP traffic between these interfaces, including but not limited to datagrams, DHCP, ICMP, and IP Group addressing (broadcast and multicast).

18 18 ES V1.2.2 ( ) Reference architecture The reference architecture for the Data Over Cable services and interfaces is shown in figure 1.2. NOTE: This architecture illustrates the North American frequency plans only and is not normative for European applications. Refer to clause 1.1 for applicability. Distribution Hub or Headend PSTN Backbone Network Copper Pairs, DS1 or DS3 WAN Telco Return Access Concentrator (TRAC) Generic Headend Switch or Backbone Transport Adapter Local Server Facility Cable Modem Termination System Network Side Interface, CMTS-NSI Operations Support System Baseline Privacy Interface (BPI) Cable Modem Termination System Network Termination Mod Demod Security & Access Controller Data Over Cable System OSS Interface, DOCS-OSSI Cable Modem Termination System Downstream RF Interface Video 1 Video 2. Data Data... Combiner Upstream splitter and filter bank MHz. Cable Modem Termination System Upstream RF Interface Tx Rx 5 42MHz Fiber Distribution Network O/E Node O/E Node O/E Node Cable Modem to RF Interface, Coax Cable Modem Telco return Cable Modem Telco Return Interface, CMTRI Cable Modem to CPE Interface, CMCI Customer Premise Equipment WAN Remote Server Facility Figure 1.2: Data Over Cable reference architecture

19 19 ES V1.2.2 ( ) Categories of interface specification The basic reference architecture of figure 1.2 involves five categories of interface: Data Interfaces - These are the CMCI [4] and CMTS-NSI [3], corresponding respectively to the cable-modemto-customer-premises-equipment (CPE) interface (for example, between the customer's computer and the cable modem), and the cable modem termination system network side interface between the cable modem termination system and the data network. Operations Support Systems Interfaces - These are network element management layer interfaces between the network elements and the high-level OSSs (operations support systems) which support the basic business processes, and are documented in [6]. Telephone Return Interface - CMTRI - This is the interface between the cable modem and a telephone return path, for use in cases where the return path is not provided or not available via the cable network, and is documented in [5]. RF Interfaces - The RF interfaces defined in the present document are the following: - Between the cable modem and the cable network. - Between the CMTS and the cable network, in the downstream direction (traffic toward the customer). - Between the CMTS and the cable network, in the upstream direction (traffic from the customer). Security Interfaces: - Baseline Data Over Cable security is defined in [17]. NOTE: This architecture illustrates the North American frequency plans only and is not normative for European applications. Refer to clause 1.1 for applicability Data Over Cable service interface documents A list of the documents in the Data Over Cable Service Interface Specifications family is provided below. For updates, please refer to URL Designation Title SP-CMCI Cable Modem to Customer Premises Equipment Interface Specification SP-CMTS-NSI Cable Modem Termination System Network Side Interface Specification SP-CMTRI Cable Modem Telco Return Interface Specification SP-OSSI Operations Support System Interface Specification SP-RFI Radio Frequency Interface Specification SP-BPI+ Baseline Privacy Plus Interface Specification SP = Specification. TP = Test Plan - a document of test procedures to validate specification conformance, interoperability or performance. TR = Technical Report (provides a context for understanding and applying the specification or initial ideas about possible future features) Statement of compatibility This clause applies only to the first option defined in clause 1.1. The present document specifies an interface, commonly referred to as DOCS 1.1, which is an extension of the interface specified in [6], commonly referred to as DOCS 1.0. These extensions are entirely backwards and forwards compatible with the previous specification. DOCS 1.1 compliant CMs MUST interoperate seamlessly with DOCS 1.0 CMTSs. DOCS 1.1 compliant CMTSs MUST seamlessly support DOCS 1.0 CMs. Refer to annex G for further interoperability information.

20 20 ES V1.2.2 ( ) 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For a specific reference, subsequent revisions do not apply. For a non-specific reference, the latest version applies. Referenced documents which are not found to be publicly available in the expected location might be found at [1] Void. [2] Void. [3] CableLabs: "Data Over Cable Interface Specifications, Cable Modem Termination System- Network Side Interface Specification, SP-CMTS-NSII ". [4] CableLabs: "Data-Over-Cable Service Interface Specifications, Cable Modem to Customer Premise Equipment Interface Specification, SP-CMCI-I ". [5] CableLabs: "Data-Over-Cable Service Interface Specification, Cable Modem Telephony Return Interface Specification, SP-CMTRI-I ". [6] ANSI/SCTE 22-1 (2002): "Data-Over-Cable Service Interface Specification DOCSIS 1.0, Radio Frequency Interface (RFI)" (formerly DSS-02-05). [7] EG : "Electrical safety; Classification of interfaces for equipment to be connected to telecommunication networks". [8] EIA/CEA-542-A: "Cable Television Channel Identification Plan". [9] EN : "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for cable systems". [10] EN : "Electromagnetic compatibility - Generic emission standard - Part 1: Residential, commercial and light industry". [11] EN : "Electromagnetic compatibility - Generic immunity standard - Part 1: Residential, commercial and light industry". [12] EN : "Cable networks for television signals, sound signals and interactive services - Part 1: Safety requirements". [13] EN : "Cable networks for television signals, sound signals and interactive services - Part 2: Electromagnetic compatibility for equipment". [14] EN : "Cable networks for television signals, sound signals and interactive services - Part 7: System performance". [15] EN : "Cable networks for television signals, sound signals and interactive services - Part 10: System performance for return paths". [16] EN 60950: "Safety of information technology equipment". [17] ES : "Access and Terminals (AT); Data Over Cable Systems Part 3: baseline Privacy Plus Interface Specification". [18] Code of Federal Regulations, Title 47, Part 15 (2003): "Telecommunication; Radio frequency devices".

21 21 ES V1.2.2 ( ) [19] Code of Federal Regulations, Title 47, Part 76 (2003): "Telecommunication; Multichannel video and Cable television service". [20] IEEE : "IEEE Standard for Local and Metropolitan Area Networks: Overview and Architecture". [21] IEEE 802.1Q-2003: "IEEE Standards for Local and metropolitan area networks - Virtual Bridged Local Area Networks". [22] "Internet Assigned Numbers Authority: "Internet Multicast Addresses", [23] ANSI/SCTE-24-3 (2001): "IPCablecom Part 3: Network Call Signalling Protocol for the Delivery of Time Critical Services over Cable Television Networks Using Data Modems". [24] ANSI/SCTE-24-4 (2001): "IPCablecom Part 4: Dynamic Quality of Service for the Provision of Real-Time Services over Cable Television Networks Using Data Modems". [25] IEC : "Radio-frequency connectors - Part 24: Radio-frequency coaxial connectors with screw coupling, typically for use in 75 ohm cable distribution systems (Type F)". [26] ISO/IEC : "Information technology - ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER)". [27] ISO/IEC :1998: "Information technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Specific requirements - Part 2: Logical link control". [28] ISO/IEC (2001): "Information technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Specific requirements - Part 3: Carrier sense multiple access with collision detection (CSMA/CD) access method and physical sublayer specifications". [29] ISO/IEC (1998): "Information technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Common specifications - Part: 3 Media Access Control (MAC) Bridges". [30] ISO/IEC (1995): "Information technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Common specifications - Part 1: Medium Access Control (MAC) service definition". [31] ITU-T Recommendation G.711: "Pulse code modulation (PCM) of voice frequencies". [32] ITU-T Recommendation H (2000) ISO/IEC (2000): "Information technology - Generic coding of moving pictures and associated audio information: Systems". [33] ITU-T Recommendation J.83 (1997), annex B: "Digital multi-programme systems for television, sound and data services for cable distribution". [34] ITU-T Recommendation X.25 (1996): "Interface between Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE) for terminals operating in the packet mode and connected to public data networks by dedicated circuit". [35] ITU-T Recommendation Z.100 (2002): "Specification and Description Language (SDL)". [36] National Cable Television Association: "NCTA Recommended Practices for measurement on Cable Television Systems", Washington DC, 3rd Edition, [37] IETF RFC 2474 (1998): "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers". [38] IETF RFC 868 (1983): "Time Protocol".

22 22 ES V1.2.2 ( ) [39] IETF RFC 1042 (1988): "A Standard for the Transmission of IP Datagrams over IEEE 802 Networks". [40] IETF RFC 1388 (1993): "RIP Version 2 Carrying Additional Information". [41] IETF RFC 1157 (1990): "A Simple Network Management Protocol (SNMP)". [42] IETF RFC 1350 (1992): "The TFTP Protocol (Revision 2)". NOTE: Further work is seen in RFCs 1782, 1783, 1784, 1785, 2347, 2348 and [43] IETF RFC 1493 (1993): "Definitions of Managed Objects for Bridges". [44] IETF RFC 3232 (2002): "Assigned Numbers", [45] IETF RFC 1812 (1995): "Requirements for IP Version 4 Routers". [46] IETF RFC 2104 (1997): "HMAC: Keyed-Hashing for Message Authentication". [47] IETF RFC 2131 (1997): "Dynamic Host Configuration Protocol". [48] IETF RFC 2132 (1997): "DHCP Options and BOOTP Vendor Extensions". [49] IETF RFC 2212 (1997): "Specification of Guaranteed Quality of Service". [50] IETF RFC 3376 (2002): "Internet Group Management Protocol, Version 3". [51] IETF RFC 2349 (1998): "TFTP Timeout Interval and Transfer Size Options". [52] IETF RFC 2669 (1999): "DOCSIS Cable Device MIB Cable Device Management Information Base for DOCSIS compliant Cable Modems and Cable Modem Termination Systems". [53] IETF RFC 2786 (2000): "Diffie-Helman USM Key Management Information Base and Textual Convention". [54] IETF RFC 3046 (2001): "DHCP Relay Agent Information Option". [55] NIST, FIPS PUB (2002): "Secure Hash Standard". [56] Void. [57] IETF RFC 3413 (2002): "Simple Network Management Protocol (SNMP) Applications". 3 Definitions and abbreviations 3.1 Definitions For the purposes of the present document, the following terms and definitions apply: active service flow: admitted Service Flow from the CM to the CMTS which is available for packet transmission Address Resolution Protocol (ARP): protocol of the IETF for converting network addresses to 48 bit Ethernet addresses admitted service flow: Service Flow, either provisioned or dynamically signalled, which is authorized and for which resources have been reserved but is not active American National Standards Institute (ANSI): US standards body Asynchronous Transfer Mode (ATM): protocol for the transmission of a variety of digital signals using uniform 53-byte cells

23 23 ES V1.2.2 ( ) authorization module: authorization module is an abstract module that the CMTS can contact to authorize Service Flows and Classifiers. The authorization module tells the CMTS whether the requesting CM is authorized for the resources it is requesting availability: in cable television systems, availability is the long-term ratio of the actual RF channel operation time to scheduled RF channel operation time (expressed as a percent value) and is based on a Bit Error Rate (BER) assumption bandwidth allocation map: MAC Management Message that the CMTS uses to allocate transmission opportunities to CMs Bridge Protocol Data Unit (BPDU): spanning tree protocol messages as defined in RFC 1350 [42] broadcast addresses: predefined destination address that denotes the set of all data network service access points burst error second: any Errored Second containing at least 100 errors Cable Modem (CM): modulator-demodulator at subscriber locations intended for use in conveying data communications on a cable television system Cable Modem Termination System (CMTS): cable modem termination system, located at the cable television system headend or distribution hub, which provides complementary functionality to the cable modems to enable data connectivity to a wide-area network Cable Modem Termination System - Network Side Interface (CMTS-NSI): interface, defined in CableLabs, SP-CMTS-NSI-I [3], between a CMTS and the equipment on its network side Cable Modem to CPE Interface (CMCI): interface, defined in CableLabs, SP-CMCI-I [4], between a CM and CPE Carrier Hum Modulation: peak-to-peak magnitude of the amplitude distortion relative to the RF carrier signal level due to the fundamental and low-order harmonics of the power-supply frequency Carrier-to-Noise Ratio (C/N or CNR): square of the ratio of the root mean square (rms) of the voltage of the digitally-modulated RF carrier to the rms of the continuous random noise voltage in the defined measurement bandwidth NOTE: If not specified explicitly, the measurement bandwidth is the symbol rate of the digital modulation; for video it is 4 MHz. CPE Controlled Cable Modem (CCCM): refer to the DOCSIS Cable Modem to Customer Premises Equipment Interface (CMCI) specification classifier: set of criteria used for packet matching according to TCP, UDP, IP, LLC, and/or 802.1P/Q packet fields NOTE: A classifier maps each packet to a Service Flow. A Downstream Classifier is used by the CMTS to assign packets to downstream service flows. An Upstream Classifier is used by the CM to assign packets to upstream service flows. Composite Second Order beat (CSO): peak of the average level of distortion products due to second-order non-linearities in cable system equipment Composite Triple Beat (CTB): peak of the average level of distortion components due to third-order non-linearities in cable system equipment cross-modulation: form of television signal distortion where modulation from one or more television channels is imposed on another channel or channels customer: See End User. Customer Premises Equipment (CPE): equipment at the end user's premises; may be provided by the end user or the service provider Data Link Layer (DLL): layer 2 in the Open System Interconnection (OSI) architecture; the layer that provides services to transfer data over the transmission link between open systems