SPL , Cisco Systems, Inc. All rights reserved.

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1 2001, Cisco Systems, Inc. All rights reserved. 1

2

3 Introduction to Cable-Based Internet Access Session 2001, Cisco Systems, Inc. All rights reserved. 3

4 Agenda Euro-DOCSIS Overview Introduction to RF CMTS Products Lab Configuration Modem Initialization 2001, Cisco Systems, Inc. All rights reserved. 4

5 Cable Evolution The video signal is transmitted over fiber to the node, where it is converted to an electrical signal and forwarded to the subscriber over existing coaxial cable Provision is made to support return traffic for future services Cable Serving Area HFC > 2000 Homes Head-End Fiber N Coax Typically Fewer than Five Amplifiers in Cascade 2001, Cisco Systems, Inc. All rights reserved. 5

6 Cable Plant Components Node Node Node ubr Head-End Hub Broadband Router Node Lifetime VH-1 Packetized Data NICK E! PSTN Internet Hub Hub Node Node COAX Tap Node Node Node Drop Cable Modem PC 2001, Cisco Systems, Inc. All rights reserved. 6

7 Euro-DOCSIS Overview DOCSIS is a consortium of ATT, Comcast, Cox, AOL/Time Warner, Rogers, MediaOne, and CableLabs Euro-DOCSIS is an initiative of TOCOF (telecom Ovcer Cable Operator Forum) and certification is done by Tcomlabs Euro-DOCSIS is a standard supporting DS modulations of QAM 64 and QAM 256, DS FEC of Annex B, US modulations of QPSK and QAM 16, in-band control channels, MPEG framing, and RSA key distribution 2001, Cisco Systems, Inc. All rights reserved. 7

8 (Euro)DOCSIS Overview TDMA Carrier Freq Range MHz Channel Width MHz. Band Rate MSps Raw Bit Rate Mbps Payload Rate Mbps QAM b/sym QAM-64 6 b/sym QAM-16 4 b/sym QPSK b/sym , Cisco Systems, Inc. All rights reserved. 8

9 RF Spectrum 110/220 V Electrical Signal 60 Hz CB 27 MHz Frequency Spectrum Channel 2 55 MHz Satellite Frequency IF RF (VHF and UHF) Microwave Infrared 5 45 MHz MHz Above 1 GHz Visible Light Ultra Violet X-Rays Gamma Rays Radio Freq (RF) Above audio to infrared Down Stream (DS) Cable company to subscriber MHz Up Stream (US) Subscriber to cable company 5 42 MHz 2001, Cisco Systems, Inc. All rights reserved. 9

10 Frequency Allocation Over Air Cable Over Air Cable Over Air Cable Short Wave Ham Land Maritime Mobile CB HAM Land Mobile Radio and Paging HAM 2 F I 7 13 K W 150 (19) (36) (MHZ) AA Aero Navigation TV Channels 2 4 Astronomy Aero Navigation TV Channels Telemetry HAM Gov t Fixed Mobile Harbor Navigation Coast Guard TV Channels 7 13 Gov t Fixed Mobile FM Research Other Air Traffic Control Research Gov t Fixed Mobile Including Aero Communications Land Mobile 136 HAM HAM Other MHZ (18) (37) (61) A-6 Aero Navigation Aircraft Voice A 1 A (14) E YY Over Air Cable Land Mobile ZZ 63 UHF TV Channels UHF 86 Over Air Cable Various Services Trouble Area for CATV 2001, Cisco Systems, Inc. All rights reserved. 10

11 Coaxial Cable Transmission Systems Cable TV fundamental unit of measurement: (dbmv) Decibel-milliVolt or (dbµv) Decibel-microVolt with reference of: 0 dbmv = 1 millivolt measured across impedance of 75 ohms = 1/1000 volt measured across impedance of 75 ohm =.001 volt measured across impedance of 75 ohm = 10-3 volt measured across impedance of 75 ohm 2001, Cisco Systems, Inc. All rights reserved. 11

12 Basic RF and Multiplexing Concepts Multiplexing TDM (Time Division Multiplexing) TDMA (Time Division Multiple Access) FDM (Frequency Division Multiplexing) Modulation QPSK (Quadrature Phase Shift Keying) QAM (Quadrature Amplitude Modulation) FEC (Forward Error Correction) (Reed Solomon Coding Algorithm) 2001, Cisco Systems, Inc. All rights reserved. 12

13 Types of Multiplexing TDM FDM Sharing time on the same media Frame relay is TDM Sharing freq spectrum on the same media Video over cable is FDM Slow Bit Stream 1 Time Slow Bit Stream 2 Time Signal 1 Frequency Signal 2 Frequency TDM Signal Fast Bit Stream FDM Signal Time Modulated Signal Frequency 2001, Cisco Systems, Inc. All rights reserved. 13

14 (Euro)DOCSIS Modulation Modes Downstream: 64 QAM; 256 QAM Upstream: QPSK; 16 QAM QAM Constellation 2001, Cisco Systems, Inc. All rights reserved. 14

15 Composite Downstream Spectrum 0 Amplitude dbmv Multiple NTSC Channels Video Down Stream QAM Data Video MHz 6.0 MHz 6.0 MHz Frequency MHz QAM Quadrature Amplitude Modulation 2001, Cisco Systems, Inc. All rights reserved. 15

16 Head-End RF Levels RF downstream +55 to +58 dbmv As per upconverter specs RF Upstream 0 dbmv nominal Head-end commands modems until nominal level is reached Nominal level adjustable 10 dbmv to +25 dbmv 2001, Cisco Systems, Inc. All rights reserved. 16

17 Spectrum Analyzers Required for Installation 2001, Cisco Systems, Inc. All rights reserved. 17

18 Upstream Impairments Ingress noise Impulse noise Reflections Laser clipping Common path distortion Corroded connections Amateur, shortwave, CB radio, bad grounding and connections Power line arcing, bad grounding and connections Unterminated drops Misaligned amplifiers, contention intervals 2001, Cisco Systems, Inc. All rights reserved. 18

19 Common Networking Problems Noise Unwanted signals RF amplifiers introduce noise Electrical and Magnetic Interference (EMI) Thermal noise C/N measure of video quality Co channel Ingress due to other channels appearing at the desired channel frequency Ingress Interference of leaking signals 2001, Cisco Systems, Inc. All rights reserved. 19

20 Need for Service Classes (COS) Different service levels enable different pricing plans for the individual subscribers based on the type of applications they will be running MSO has policing capability against misbehaving users; no single CM can monopolize available channel bandwidth resource Advanced QoS enables real-time and non real-time traffic to coexist on the same channel 2001, Cisco Systems, Inc. All rights reserved. 20

21 ubr Product Positioning Performance and Density Medium Robust Functionality Large MSO/ISPs Medium/Large MSO/ISPs Small MSO/ISPs ubr7100 ubr7223 ubr7246-vxr ubr7246 ubr10012 Small MSO Network Size Large 2001, Cisco Systems, Inc. All rights reserved. 21

22 ubr7100e Cost effective CMTS for MDUs and small HFC plants Compact 2RU package NPE-175 equivalent motherboard Fixed configuration MC11 or MC14 line card One single wide port adapter 100% ubr7200 SW compatible Optional integrated upconverter Optional national clock module Optional redundant power supply 2001, Cisco Systems, Inc. All rights reserved. 22

23 ubr7246vxr Hardware Overview Commonalities with Cisco 7200 CPU card NPE225,300,400 I/O card MII or RJ45 FE port 2 PA slots 2001, Cisco Systems, Inc. All rights reserved. 23

24 ubr7246vxr Chassis (Front) FE MII Port Adapter Slots PCMCIA Flash Cards 8E Installed in Left Slot I/O Card Console Aux 4Line Card Slots Fan Tray LEDs Upstream F Connector MC11 Downstream F Connector 2001, Cisco Systems, Inc. All rights reserved. 24

25 ubr7246 Chassis (Back) NPE 225/300 /400 2 Power Supply Slots AC or DC Power Supply 2001, Cisco Systems, Inc. All rights reserved. 25

26 UBR 7246 Networking Processing Engine NPE-225,300,400 (up to 512 MB DRAM) + Dram + Flash + In/Out Controller CORE Common Equipment + POWER Option, Etc. Port Adaptors (QTY 2) PA ATM 100 OC-3 Rate Interface PA 4E (Four IEEE Base T Ethernet) PA 8E (Eight IEEE Base T Ethernet) PA FE-TX (100 Base T Fast Ethernet e/w RJ-45) PA FE-FX (100 Base T Fast Ethernet e/w SC Optical Connector) DPT, Optical, Gigabit + Service Adapter Cables + Software and License ubr Modem Cards ubr-mc1x1 ubr-mc1x6 ubr-mc2x8 2001, Cisco Systems, Inc. All rights reserved. 26

27 ubr10012 Series High-End Broadband Router Highly scalable architecture Optimized for aggregation Industry leading capacity, performance and reliability Extension of 10000ESR technology Investment protection Proven Cisco technology 2001, Cisco Systems, Inc. All rights reserved. 27

28 ubr10012 Components RF Line Cards Blower Assembly Display Module Power Modules Utility Cards LAN/WAN Line Cards Performance Routing Engines 2001, Cisco Systems, Inc. All rights reserved. 28

29 ubr10012 System Features System cards Full card level redundancy with hot swap Specialized card types for optimal density and performance System interconnect Reliable fully passive midplane Speed independent point-to-point data path Dedicated control plane interface Dedicated redundancy state comm link Power system Dual redundant, load sharing power modules DC and AC power options 48 volt power distribution with local conversion Cooling system Front-to-back, bottom-to-top airflow Modular, variable speed blower assembly Failsafe design, replaceable online , Cisco Systems, Inc. All rights reserved

30 Parts Required for 6 Installation ubr Upconverter Cable modem(s) Coax (8 12 pieces) Diplex filter Splitters Attenuator pads DHCP/TOD/TFTP servers 2001, Cisco Systems, Inc. All rights reserved. 30

31 6 Plant Block Diagram ubr7246 Servers Upconverter IF In RF Out 20 db Pad Modems Diplex Filter 20 db Pad Hi Lo -7 db Common 4 Way Splitter 2001, Cisco Systems, Inc. All rights reserved. 31

32 1+1 Redundant Configuration IP Cloud Aggregate Router Standby CMTS Router Active CMTS Router IF Upconverter w/ SNMP Splitter Combiner HFC 2001, Cisco Systems, Inc. All rights reserved. 32

33 Required Servers for DOCSIS DHCP (Dynamic Host Configuration Protocol) Provides IP addresses for modems and PCs TOD (Time of Day) System time clock TFTP (Trivial File Transfer Protocol) Modem configuration files 2001, Cisco Systems, Inc. All rights reserved. 33

34 Cisco Network Registrar Overview Cisco Network Registrar provides integrated DHCP and DNS services Can also integrate ToD server and TFTP server (depending on size of network) Provides DHCP safe failover and dynamic DNS updates (notify and IXFR) Provides enhancements specific for cable networks 2001, Cisco Systems, Inc. All rights reserved. 34

35 Cisco Network Registrar in Head-End Internet DHCP/DNS Network Registrar TFTP Server Security Server Cable Modem Termination System Rack Remote Access Server Rack Routers, Etc. 2001, Cisco Systems, Inc. All rights reserved. 35

36 Cable Modem Initialization Head End Interface Clock Synch B cast (One per 1.63 msec) UCD B cast US Channel Descriptor, DS Channel ID and Minislot Size (One per Second per US Channel) MAP B cast Contains US Time Sharing Information (One per 4 ms per US Channel) Cable Modem Scan DS for QAM Wait for Clock Synch Set Signaling Clock Wait for UCD Set US Channel Frequency Wait for MAP Look for Shared Request Slots (Available Every 2 Seconds) 2001, Cisco Systems, Inc. All rights reserved. 36

37 Cable Modem Initialization Head End Interface Ranging Response (Can Be Sent as Needed) US/DS Frequency Can Be Changed Contains Temp SID Fails if No/Bad US Or Too Many Modems Keep Alive (One per 30 Second per Modem) Ranging Response (Can Be Sent As Needed) US/DS Frequency Can Be Changed) Cable Modem Ranging Response Only in Shared Request Slots Use USE = 0 (Service ID) Wait for Ranging Response Adjust Clock (in 6.25 US Ticks) Adjust Power (in 0.25 db Steps) Wait for 1st Keep Alive Ranging Request Now in Allocated Maintenance Slot Link Establishment (Cable Modem HFC Interface Line Protocol Up, Not Online Yet) Maintain Station Link Using Periodic Keep Alives Link Broken if Missed 16 Keep Alives 2001, Cisco Systems, Inc. All rights reserved. 37

38 Cable Modem Initialization Head End Interface Map B Cast Contains US Time Sharing Info (One per Four ms per US Channel DHCP Response Contains ID Addr, Default GW, ToD Server, TFTP Server Addr and TFTP Boot Config File Name From a DHCP Server ToD Response Contains Time of Day RFC 868, not NTP From a ToD Server Cable Modem Bandwidth Request Only in Shared Request Slots Use Temp SID (Service ID) (Needed for Every Use of US) DHCP Request Now in Allocated Slots ToD Response Now in Allocated Slots 2001, Cisco Systems, Inc. All rights reserved. 38

39 Cable Modem Initialization Head End Interface TFTP Boot File Transfer Contains QoS Parameters Specifies Privacy, New Software Downloads, Etc. From an TFTP Server Cable Modem TFTP Boot Request Send TFTP Boot File Name Now in Allocated Slots Registration Response Contains Assigned SID Modem Registered Fail if QoS Not Available Or Authentication Failed Cable Modem Online Registration Request Send QoS Parameters Now in Allocated Slots Maintain Station Link Using Periodic Keep Alives May Need to Hop Upstream Frequency Due to Noise (Means Link Reset) 2001, Cisco Systems, Inc. All rights reserved. 39

40 Where to Go for More Info specifications.html solutions/network/cable.shtml , Cisco Systems, Inc. All rights reserved. 40

41 Introduction to Cable-Based Internet Access 2001, Cisco Systems, Inc. All rights reserved. 41

42 Please Complete Your Evaluation Form 2001, Cisco Systems, Inc. All rights reserved. 42

43 2001, Cisco Systems, Inc. All rights reserved. 43