Coresma NeMo CMTS User manual

NeMo CMTS
User’s Guide

010804

NeMo CMTS User’s Guide
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Important Notice
This guide is delivered subject to the following conditions and restrictions:
§This guide contains proprietary information belonging to Coresma, Ltd. Such
information is supplied solely for the purposeof explicitly assisting properly
authorized users of NeMo CMTS System™.
§No part of the contents may be used for any other purpose, disclosed to any
person or firm or reproduced by any means, electronic and mechanical, without
the express prior written permission of Coresma, Ltd.
§The text and graphics are for the purpose of illustration and reference only. The
specifications on which they are based are subject to change without notice.
§The software described in this document is furnished under a license. The
software may be used or copied only in accordance with the terms of that
agreement.
§Information in this document is subject to change without notice. Corporate and
individual names and data used in examples herein are fictitious unless
otherwise noted.
Copyright 2001 Coresma, Ltd.
NeMo CMTS, NeMo Modem are trademarksof Coresma Ltd. All other product names
are trademarks or registered trademarks of their respective owners, and are hereby
acknowledged.

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Safety Instructions
Caution! Risk of Electric Shock!
Do not open the cover under any circumstances.
§Dangerous voltages inside.
§No user serviceable parts inside.
§Refer to qualified service personnel.
Explanation of Graphical Symbols:
This symbol is intended to alert the user to the presence of non-insulated
"dangerous voltage" within the product's enclosure that may be of sufficient magnitude
to constitute a risk of lethal electric shock to persons.
This symbol is intended to alert the user to the presence of important operating,
maintaining and servicing instructions in the literature accompanying the appliance.
Failing to comply with this instruction may result in a hazard.

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§Power sources-Connect this unit only to power sources specified in the
Operating Instructions, and as marked on the unit back.
§This unit must be disconnected from power supply prior to servicing.
§When disconnecting the AC power cord, pull it out by the AC power plug. Do
not pull the cord itself.
§Never handle the AC power plug or cable with wet hands, as this could result in
fire or an electrical shock.
§Power cords should be routed to avoid being severely bent, pinched, or walked
upon. Pay particular attention to the cord from the unit to the power socket.
§To help prevent electric shock and fire hazard avoid connecting the unit through
an extension cord.
§Do not remove or attach cables to the unit during a thunderstorm.
§The CMTS must be installed near a wall power outlet.
§Only a certified technician is allowed to connect and disconnect cables to the
CMTS.
§Please install the CMTS on a stable horizontal surface that can support the
weight of the CMTS, approximately 4.0 kg.
§Do not place heavy objects on top of the box.
§Do not try to bend the box.
Environmental Conditions for the NeMo CMTS
§This unit must be installed in an office environment in a temperature-controlled
location where the temperature is between 0°and 40°Celsius, far away from
rain, water sources, heat sources, inflammable liquids, inflammable vapors, dust
and flammable materials.
§If installed in a rack, air ventilation should be provided for the CMTS. The
surrounding temperature inside the rack around the CMTS should not be over
40º Celsius.
§Do not impair the airflow around the CMTS especially near the air vents located
at the sides of the unit as shown in the figure below. This may result in a hazard.

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§The CMTS was designed to work at heights between–200 meters below sea level
and to 2000 meters above sea level.
§If the CMTS is brought in from a cold place to a hotter place, condensation may
occur. Wait one hour before connecting to power.

NeMo CMTS User’s Guide
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About This Guide
This guide describes how to prepare your site and install the NeMo CMTS system. It is
intended for qualified engineers familiar with RF networks.
This guide contains the following chapters:
§Chapter 1–Introduction introduces the NeMo CMTS system, describes its
components and provides technical specifications.
§Chapter 2-Site Preparation describes the hardware, software, and
environmental requirements necessary for the installation at the headend and
end-user sites.
§Chapter 3-Installing the NeMo CMTS describes the procedure for installing the
NeMo CMTS system and testing an end-user site from your location.
§Appendix A –Rlogin Commands describes the various system commands used to
control the CMTS
§Appendix B–NetHotel lists additional system commands for controlling the
optional NetHotel software
§Appendix C –Boot Parameters lists the parameters available during the boot
sequence of the CMTS.
§Appendix D –Multiple MAC Modems describes using multiple NeMo modems
in a network.
§Appendix E –Glossary of Terms defines technical terms used in this document.
§Appendix F –Technical Specifications lists the specifications of the NeMo CMTS
§Contacting Coresma lists the various ways to contact Coresma Sales and
Support.

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Table of Contents
IMPORTANT NOTICE.......................................................................................................................................................I
SAFETY INSTRUCTIONS..............................................................................................................................................II
Explanation of Graphical Symbols:.....................................................................................................................ii
Environmental Conditions for the NeMo CMTS............................................................................................iii
ABOUT THIS GUIDE........................................................................................................................................................V
TABLE OF CONTENTS....................................................................................................................................................VI
INTRODUCTION................................................................................................................................................................1
About this chapter:.................................................................................................................................................1
WHATISTHE NEMO CMTS SYSTEM?...................................................................................................................1
System Components...............................................................................................................................................1
NEMO CMTS DIAGRAM..........................................................................................................................................4
OVERVIEW....................................................................................................................................................................5
HOWTHE CMTS WORKS.........................................................................................................................................6
NEMO HEADEND UNIT............................................................................................................................................7
Configuring the CMTS.........................................................................................................................................8
MAIN FEATURES.........................................................................................................................................................8
ARCHITECTURE...........................................................................................................................................................8
OPERATION AND MAINTENANCE...........................................................................................................................8
INSTALLATION FEATURES.........................................................................................................................................9
INTRODUCINGTHE NEMO CABLE MODEM..........................................................................................................9
SYSTEM ARCHITECTURE..........................................................................................................................................10
SYSTEM CONNECTIVITY...........................................................................................................................................11
HEADEND HARDWARE...........................................................................................................................................13
CMTS Functionality ...........................................................................................................................................13
RF Transmitter.....................................................................................................................................................13
RF Burst Receiver ................................................................................................................................................14
NeMo Modem Transmitter ................................................................................................................................14
Channel Controller...............................................................................................................................................14
IP Host Address....................................................................................................................................................14

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HEADEND SOFTWARE.............................................................................................................................................14
CMTS Embedded Code.......................................................................................................................................15
NEMO CABLE MODEM...........................................................................................................................................15
CM Controller......................................................................................................................................................16
Burst Transmitter................................................................................................................................................16
Downstream IF Receiver ....................................................................................................................................16
Tuner and Diplexer .............................................................................................................................................16
Multiple MAC Modems .....................................................................................................................................16
APPLICATIONS..........................................................................................................................................................16
SYSTEM WITHOUT MANAGEMENT.......................................................................................................................17
SYSTEM WITH MANAGEMENT...............................................................................................................................17
SITE PREPARATION......................................................................................................................................................18
About this chapter:...............................................................................................................................................18
OVERVIEW..................................................................................................................................................................18
System Components ............................................................................................................................................18
BASIC CONFIGURATION..........................................................................................................................................19
PREPARINGTHE HEADEND SITE...........................................................................................................................21
Preparing the Management Computer............................................................................................................21
Preparing the RF Network .................................................................................................................................23
Preparing the Ethernet Network Parameters..................................................................................................25
PREPARING A LOCAL END-USER SITE.................................................................................................................26
Installation Configuration..................................................................................................................................27
INSTALLINGTHE NEMO CMTS................................................................................................................................29
About this Chapter...............................................................................................................................................29
PART1: SETTING UP THE CMTS AND MODULATOR CONNECTION.............................................................29
Connecting the CMTS and Modulator............................................................................................................29
Calibrating the RF Signals and Connecting to the RF Network.................................................................31
PART2. SETTING UP THE MANAGEMENT COMPUTER(S)................................................................................35
Configuring the CMTS for the First Time: CMTS Configuration.............................................................36
Configuring the CMTSUsing FOCS..............................................................................................................40
PART3: SETTING UP AN END-USERSITE............................................................................................................41
Before You Begin..................................................................................................................................................41
Installing the NeMo Modem..............................................................................................................................41
Installing and Using the NeMo Tool ...............................................................................................................42
RLOGIN C OMMANDS ....................................................................................................................................................45

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INTRODUCTION.........................................................................................................................................................45
REQUIREMENTS.........................................................................................................................................................45
AUTHORIZATION......................................................................................................................................................45
RLOGIN PASSWORD..................................................................................................................................................46
SHELL COMMANDS..................................................................................................................................................46
dir............................................................................................................................................................................46
cd .............................................................................................................................................................................46
show........................................................................................................................................................................46
set ............................................................................................................................................................................46
help..........................................................................................................................................................................46
quit..........................................................................................................................................................................47
reboot......................................................................................................................................................................47
write........................................................................................................................................................................47
ls..............................................................................................................................................................................47
CONTROL VARIABLES..............................................................................................................................................47
Root directory........................................................................................................................................................47
Service directory ...................................................................................................................................................48
Upchan directory..................................................................................................................................................49
Freq_hopp_table directory...................................................................................................................................51
Downchan directory ............................................................................................................................................51
CMTS directory....................................................................................................................................................52
mgmt directory .....................................................................................................................................................54
Stats directory .......................................................................................................................................................55
ip_cfg directory.....................................................................................................................................................57
Boot_cfg directory ................................................................................................................................................58
Radius Directory ..................................................................................................................................................58
CM Operation Mode directory ..........................................................................................................................62
NETHOTEL .....................................................................................................................................................................65
NAT/SETTINGS DIRECTORY...................................................................................................................................65
BOOTPARAMETERS.....................................................................................................................................................69
MULTIPLE MAC MODEMS.........................................................................................................................................71
PREFACE.....................................................................................................................................................................71
MULTIPLE MAC DETAILED DESCRIPTION..........................................................................................................71
MODEM IDENTIFICATION.......................................................................................................................................71
Modem Ethernet Operation Mode....................................................................................................................71
MAC ADDRESS TRANSLATION.............................................................................................................................72

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IP messages handling ..........................................................................................................................................72
ARP messages handling......................................................................................................................................72
DHCP messages handling..................................................................................................................................72
DHCP Block Mode..............................................................................................................................................72
MULTI MAC AUTHENTICATION IMPLICATIONS..............................................................................................73
MULTI MAC FORWARDER IMPLICATIONS.........................................................................................................73
GLOSSARYOF TERMS..................................................................................................................................................74
TECHNICAL SPECIFICATIONS ....................................................................................................................................76
NeMo CMTS ........................................................................................................................................................76
NeMo Modem.......................................................................................................................................................77
CONTACTING CORESMA.............................................................................................................................................79
INDEX ..............................................................................................................................................................................80

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CHAPTER 1
Introduction
This chapter introduces the NeMo CMTS system, describes the system components, and
presents a system diagram and lists its technical specifications.
About this chapter:
§What is the NeMo CMTS System?, Describes the components and features of
the NeMo CMTS system.
§NeMo CMTS Diagram, page 4, provides a diagram of the NeMo CMTS system.
§Technical Specifications,page 5,provides the technical specifications of the
NeMo CMTS and the NeMo modem.
What is the NeMo CMTS System?
The NeMo CMTS system is a high-speed two-way RF cable modem solution. NeMo is
designed for a distributed node architecture for homes, multiple dwelling units,
campuses, executive offices, and hotels. It is comprised of an intelligent RF bridge and
can be managed remotely. This enables operators and ISP's to manage dispersed CATV
networks from one control station.
System Components
The NeMo CMTS is comprised of the following components:
§NeMo CMTS, page 1.
§Management Software, page 2.
§NeMo Modem, page 3.
NeMo CMTS
The NeMo CMTS resides at the headend and provides up to a 10Mbps connection for
high-speed delivery of Internet content and other on-line services. The main objective of
the NeMo CMTS is to emulate an Ethernet LAN over a cable television network, and
connect subscribers' PCs and local servers via an IP router.

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The NeMo CMTS features:
§Excellent performance in noisy networks
§Flexible installation and configuration
§Ideal solution for MDUs, hotels, and campuses
§Rack mount or stand alone design
Management Software
The FOCS management software resides at the headend and provides the services of a
remote workstation through a classic, client-server SNMP web-based architecture and is
comprised of the following components:
§TFTP Services for software upgrades
§Serial connection for local monitoring
§The management software features:
§Tracks and monitors network performance
§Tracks and monitors the performance of NeMo modems
§Collects performance and billing statistics
§Enables authorization of all users
§Assigns QoS

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§Initiates alarms
§Downloads software upgrades
NeMo Modem
The NeMo modem is a compact, user-friendly modem designed to suit the access needs
of subscribers. Designed to plug and play, it does not require any software installation or
preset attenuation. Once it is connected, the NeMo modem auto-downloads its operating
software and is fully manageable and remotely diagnosed. The NeMo modem features:
§ElastreamTM, a real-time resource allocation algorithm, delivers upstream packets
at a higher success ratio than modems without such algorithms
§Low cost, enables profitable operation in situations where density issues exist or
where operators need a quick return to justify service commitments
§Robust networking capabilities enable the modem to overcome the challenges of
noisy upstream networks by providing QPSK modulation for both upstream and
downstream, frequency hopping, frame correction, and packet fragmentation
§Highly flexible QoS, enables operators to adjust the upstream and downstream
bandwidth per subscriber depending on the class of service to which they are
subscribed

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NeMo CMTS Diagram

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The NeMo CMTS diagram illustrates the following:
§The NeMo CMTS resides at the headend site, offering access to high-speed
delivery of Internet and other on-line services to subscribers. It handles the
downstream and upstream channels. The CMTS also manages and controls the
entire network in real time. It performs real time network management functions
and controls upstream and downstream traffic intelligence.
§The IF Agile Modulator connects to the NeMo CMTS and converts the IF input
frequency into the desired RF channel output frequency.
§The NeMo management software resides at the headend site. It controls the
entire system in real time and off-line, and enables the system operator to
perform monitoring and management functions.
§The NeMo modem resides at the end-user’s site providing high-speed
connectivity at speeds of up to 10Mbps via the existing cable infrastructure. It is
connected to the Ethernet board in the end-user’s computer.
oThe downstream channel goes from the NeMo CMTS at the
headend site to the NeMo modem at the end-user’s site.
oThe data signal (measured at back of NeMo modem) should be
10 dBmV under the video signal in the CATV. The standard
video signal is 10 dBmV, therefore the NeMo modem RF input
should be 0 dBmV. ″The splitter at the end-user’s site splits the
CATV connection. One of the splitter’s output cables is
connected to the end-user’s TV, the other cable is connected to
the NeMo modem at the end-user’s computer.
Overview
The NeMo CMTS system offers up to 10Mbps LAN access for high-speed delivery of
Internet and other online services. The remote access capability makes the NeMo CMTS
ideal for apartment complexes and high-rise residential or office buildings. The CMTS
has a bandwidth of 1.8 MHz/2.56 Mbps on the upstream and 2.8 MHz/5.12 Mbps on the
downstream. The main objective of the NeMo is to emulate an Ethernet LAN over a cable
television network and connect subscribers' computers and local servers via an IP router.
The system is comprised of an intelligent RF bridge, managed by a remote Windows NT
or UNIX workstation. The remote workstation manages all functions of authentication,
network management, subscriber database and system configuration and control, while
the NeMo CMTS distributes the Internet and other online services within the network.
The NeMo CMTS has no distance limitations. It canbe placed at a node in a
neighborhood building, hotel basement or campus.

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How the CMTS Works
The NeMo CMTS system automatically performs software downloads,utilizes constant
management messages, auto detects and keeps in memory the status of all modems in
the network, detects noise and automatically advises NeMo modems to frequency hop in
10kHz increments on the upstream. Using ElastreamTM, the NeMo CMTS system
randomly and intelligently allocates time slots to every NeMo modem, based on demand,
priority and system resources.
The design of the NeMo CMTS originates from its simplicity, scalability and
management. With robust upstream and downstream QPSK modulation, system auto
software download, auto attenuation, upstream techniques, and remote management, it
can successfully operate in today's noisiest networks. With ElastreamTM, Coresma's
algorithm for managing real-time network activity, an ordinary network becomes elastic,
enabling an operator to accommodate a growing number of users without creating the
urgency to upgrade.
The following diagram illustrates the relationship between the NeMo CMTS and your
computer.
The CMTS contains the following:

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NVRAM Parameters: Theparameters needed to configure the CMTS.
Boot (ROM): The initial code that is activated when the CMTS is turned on. The CMTS
looks to the NVRAM parameters for its configuration. It then looks for a valid boot image
(0 or 1) to determine whether to run the currently loaded software or to download new
software files from the TFTP server.
CMTS Code Program: The Flashmemory contains the CMTS application (ram.hex) and
modem code (nsu.nmc, nsu.fdp).
CMTS Application: The Modem Code area stores the latest NeMo modem application
ready for download when both a new modem connects or when one with an older
software version connects.
NeMo Headend Unit
The NeMo CMTS remotely manages all NeMo modems. The CMTS tracks and monitors
the NeMo modems and network performance, collects performance and billing statistics,
enables authorization of all users, assigns QoS, runs diagnostics, initiates alarms and
downloads software upgrades.
The cable network has traditionally been a broadcast service, where the cable headend
broadcasts signals to all subscribers. The CMTS therefore broadcasts the downstream
traffic and each modem receives its appropriate data. The upstream, however, operates
on a different topology. The headend can only receive data from one modem at a time.
The analogy of a classroom may be used to illustrate this. The teacher (or headend) can
speak to all students (modems) at once and be understood by all. Those who choose to
listen can understand everything said and students (modems) may also choose to ignore
the teacher when the teacher does not address them (modem). The teacher (headend),
though, can only listen to one student at a time.
This architecture is flexible enough to manage varying network topologies at a cable
node. By converting a cable node to a LAN, the system can accommodate a telco return
solution at a node if required. This flexibility does not require each subscriber to tie up
their phone lines, as is the case with typical telco return solutions. The router is
configured to translate individual requests upstream via an inexpensive modem rack.
This solution can serve a building, campus, hotel, hospital or any MDU, using in-feeds
from satellite, microwave, wireless LANs or any type of DSL.

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Configuring the CMTS
Either a serial terminal or RLoginapplication can be used to remotely configure the
CMTS and define its NVRAM parameters. However, first time configuration must be
performed using a serial terminal, since the RLogin connection must be done via anIP
address, and for the first time connection, the user is not familiar with the IP of the
CMTS.
Main Features
§The NeMo CMTS converts RF to digital signals (upstream) and digital signals to
IF (downstream).
§The RF chassis (What is the RF chassis? This is the first mention) contains signal
control for frequency and timing coordination with the headend (CMTS?).
§The CMTS connects to one downstream modulator and one upstream
demodulator. (this is not a feature)
§The NeMo CMTS separates the RF modules from the host (what is the host?),
which enables better signal quality.
Architecture
§Architecture flexibility to operate using NT or Unix OS
§Requires one CMTS and any standard router
§Equipment installed and operational at Cable Node
§Supports 2-way HFC, 1-way satellite (telco return), 1-way microwave or wireless,
LMDS and MMDS
Operation and Maintenance
§Varying levels of authentication.
§IP filtering for secure packet delivery.
§FOCS provides a built-in subscriber database.
§QoS offers 64kbps increments with options on data rates per subscriber.