Juniper Networks G10 CMTS · The G10 CMTS manages Internet data, voice and MPEG services. It func tions as the interface between the services networks—Internet, Publ ic Switched

Juniper Networks, Inc.

1194 North Mathilda Avenue

Sunnyvale, CA 94089

USA

408-745-2000

www.juniper.net

Part Number: 530-006435-01, Revision 2

Juniper NetworksG10 CMTS

Operations and Maintenance

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This product includes the Envoy SNMP Engine, developed by Epilogue Technology, an Integrated Systems Company. Copyright © 1986–1997, Epilogue Technology Corporation. All rights reserved. This program and its documentation were developed at private expense, and no part of them is in the public domain.

This product includes memory allocation software developed by Mark Moraes, copyright © 1988, 1989, 1993, University of Toronto.

This product includes FreeBSD software developed by the University of California, Berkeley, and its contributors. All of the documentation and software included in the 4.4BSD and 4.4BSD-Lite Releases is copyrighted by The Regents of the University of California. Copyright © 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994. The Regents of the University of California. All rights reserved.

GateD software copyright © 1995, The Regents of the University. All rights reserved. Gate Daemon was originated and developed through release 3.0 by Cornell University and its collaborators. Gated is based on Kirton’s EGP, UC Berkeley’s routing daemon (routed), and DCN’s HELLO routing protocol. Development of Gated has been supported in part by the National Science Foundation. Portions of the GateD software copyright © 1988, Regents of the University of California. All rights reserved. Portions of the GateD software copyright © 1991, D. L. S. Associates.

This product includes software developed by Maker Communications, Inc., Copyright © 1996, 1997, Maker Communications, Inc.

Juniper Networks is registered in the U.S. Patent and Trademark Office and in other countries as a trademark of Juniper Networks, Inc. G10, Internet Processor, Internet Processor II, JUNOS, JUNOScript, M5, M10, M20, M40, M40e, and M160 are trademarks of Juniper Networks, Inc. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners. All specifications are subject to change without notice.

Juniper Networks G10 CMTS Operations and MaintenanceCopyright © 2002, Juniper Networks, Inc.All rights reserved. Printed in USA.

Writer: Jerry IsaacIllustrations: Paul GilmanCovers and template design: Edmonds Design

Revision History28 February 2002—Second edition.

The information in this document is current as of the date listed in the revision history.

Juniper Networks assumes no responsibility for any inaccuracies in this document. Juniper Networks reserves the right to change, modify, transfer or otherwise revise this publication without notice.

Products made or sold by Juniper Networks (including the G10 CMTS, M5 router, the M10 router, the M20 router, the M40 router, the M40e router, the M160 router, and the JUNOS software) or components thereof may be covered by one or more of the following patents which are owned by or licensed to Juniper Networks: U.S. Patent Nos. 5,473,599, 5,905,725, 5,909,440.

YEAR 2000 NOTICE

Juniper Networks hardware and software products are Year 2000 compliant. The JUNOS software has no known time-related limitations through the year 2038. However, the NTP application is known to have some difficulty in the year 2036.

Export Restrictions

The DOCSIS Module performs encryption that is subject to U.S. Customs and Export regulations. A DOCSIS Module shall not be exported, sold or transferred to a country outside the USA and Canada without an appropriate export license from the U.S. Government. The specific Regulations governing exports of encryption products are set forth in the Export Administration Regulations, 15 C.F.R. (Code of Federal Regulations), Parts 730-774.

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Table of Contents iii

Table of ContentsAbout This Manual

Purpose .................................................................................................................ixOrganization ..........................................................................................................ixDocument Conventions ..........................................................................................x

Notes, Cautions, and Warnings........................................................................xG10 CMTS Document Set.......................................................................................xi

Chapter 1G10 CMTS Introduction ........................................................................................1

Overview ................................................................................................................1G10 CMTS Features and Functions .........................................................................2

Features and Benefits ......................................................................................2Functional Overview........................................................................................3Broadband Cable Processor ASIC.....................................................................3

G10 CMTS Components ..........................................................................................4G10 CMTS Management .........................................................................................5

Chapter 2Command Line Interface Operation .............................................................7

Management Tasks .................................................................................................7Getting Help.....................................................................................................7Defining Usernames, Passwords, and Privileges ..............................................7Setting the Clock and Date...............................................................................8Setting the Hostname ......................................................................................8Configuring Banners ........................................................................................8

RF Tasks .................................................................................................................9Slot Numbers...................................................................................................9Cable Interface Assignment ...........................................................................10Port ...............................................................................................................10Channel .........................................................................................................10Defaults .........................................................................................................10Configuring a Downstream Channel ..............................................................13Configuring an Upstream Channel .................................................................14Configuring an Upstream Modulation Profile .................................................15Enabling Upstream Multicast and Broadcast ..................................................20

NSI Tasks ..............................................................................................................20Configuring a Fast Ethernet Interface ............................................................20DHCP Server Parameters...............................................................................21

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Juniper Networks G10 CMTS Operations and Maintenanceiv

Shared Secret ................................................................................................22SNMP Server Parameters...............................................................................22Domain Name Server Address.......................................................................23File and Directory Management ....................................................................23Viewing and Saving Running Configuration...................................................24Pinging and Trace Routing ............................................................................24

Chapter 3RF Measurements..................................................................................................25

Downstream RF Measurement in CATV Mode ......................................................25Downstream RF Measurement in Spectrum Analyzer Mode .................................27Upstream RF Measurement ..................................................................................28

Appendix AAgency Certifications .........................................................................................33

Appendix BSecurity ........................................................................................................................35

Groups..................................................................................................................35Privileges ..............................................................................................................35Commands ...........................................................................................................36Users ....................................................................................................................36

Appendix CField Replaceable Units .....................................................................................37

Appendix DEIA Channel Plans .................................................................................................39

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List of FiguresList of Figures

Figure 1: Typical CMTS Location..........................................................................2Figure 2: G10 CMTS Data Flow ............................................................................5Figure 3: G10 CMTS Chassis Slot Assignment ......................................................9Figure 4: HFC Connector Module and Chassis Control Module ..........................12Figure 5: Downstream RF Signal (CATV Mode) ..................................................26Figure 6: Downstream RF Signal (Spectrum Analyzer Mode) .............................28Figure 7: Single Upstream Burst ........................................................................30Figure 8: Multiple Upstream Bursts....................................................................31

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List of TablesList of Tables

Table 1: Cable Interface to Ethernet Port Association .......................................10Table 2: Cable Interface to Downstream Channel and Port Association............10Table 3: Default Cable Interface to Upstream Channel Association...................11Table 4: Downstream Channel Parameter Ranges............................................13Table 5: Upstream Channel Parameter Ranges.................................................14Table 6: Interval Usage Codes ..........................................................................16Table 7: Upstream Modulation Profile Parameters ...........................................16Table 8: Modulation Profiles 1, 2, and 3 ...........................................................18Table 9: Modulation Profile Interval Parameters...............................................19Table 10: Group/Privilege Matrix........................................................................35Table 11: EIA Channel Plan ................................................................................39

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Juniper Networks G10 CMTS Operations and Maintenanceviii

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About This Manual ix

About This Manual

This section describes important information about the design of this document.

Purpose

The purpose of this document, Juniper Networks G10 CMTS Operations and Maintenance, is to provide detailed instructions for performing common tasks encountered during the normal operation of the G10 Cable Modem Termination System (CMTS).

The contents of this document assume that the G10 CMTS has been successfully installed in accordance with the Juniper Networks G10 CMTS Installation and Configuration manual and is fully operational.

The intended audience for this information is the technicians and engineers who will operate and maintain the G10 CMTS.

Organization

Juniper Networks G10 CMTS Operations and Maintenance is organized as follows:

Chapter 1, “G10 CMTS Introduction” – Provides a brief technical introduction to the G10 CMTS.

Chapter 2, “Command Line Interface Operation” – Provides the Command Line Interface (CLI) procedures used to perform various operational tasks on the G10 CMTS.

Chapter 3, “RF Measurements” – Provides the procedures for measuring the downstream and upstream RF signals of a DOCSIS Module using a spectrum analyzer.

Appendix A, “Agency Certifications” – Listing of government agency certifications and approvals.

Appendix B, “Security” – Describes the groups and privileges used to implement security and user access in the CLI.

Appendix C, “Field Replaceable Units” – Provides a list of Field Replacement Units defined for the G10 CMTS.

Appendix D, “EIA Channel Plans” – Provides the EIA (Electronic Industries Association) frequency plans.

Document Conventions

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Juniper Networks G10 CMTS Operations and Maintenancex

Document Conventions

The following document conventions are used in this manual:

Notes, Cautions, and Warnings

GeneralConventions

Italic font Denotes a) emphasis, b) first use of a new term, or c) a document title.

Screen Name font Denotes a) the on-screen name of a window, dialog box or field, or b) keys on a keyboard.

Software Conventions

Computer font Font denotes code or messages displayed on-screen.

Computer Bold font Font denotes literal commands and parameters that you enter exactly as shown.

<Computer Italic> font Font denotes parameter values that require a user-defined input.

The value strings are enclosed in angle brackets <...>.

[parameter] Square brackets denote optional parameters.

{parameter} Braces denote required parameters.

| Vertical bars separate parameters in a group from which you must choose only one.

↵ Return symbol indicates pressing the Enter key at the end of a command line.

A note indicates information that might be helpful in a particular situation, or information that might otherwise be overlooked.

A caution indicates a situation that requires careful attention. Failure to observe a cautionary note could result in injury or discomfort to yourself, or serious damage to the product.

A warning is intended to alert the user of the presence of uninsulated dangerous voltage within the product’s enclosure that may present a risk of electric shock.

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About This Manual xi

G10 CMTS Document Set


Pre-InstallationGuide

Installation andConfiguration

Getting Started FunctionalDescription

SNMP and Enterprise MIBSpecification

PREPARATION OPERATION REFERENCE

Operation andMaintenance

CLI Reference

530-006434-01

530-006437-01

530-006461-01530-006435-01530-006433-01

530-006459-01530-006436-01


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Juniper Networks G10 CMTS Operations and Maintenancexii

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Chapter 1G10 CMTS Introduction
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Overview

This chapter provides an introduction to the G10 Cable Modem Termination System (CMTS).

The G10 CMTS manages Internet data, voice and MPEG services. It functions as the interface between the services networks—Internet, Public Switched Telephone Network (PSTN), video servers—and the hybrid fiber/coax (HFC) network of subscribers, as shown in Figure 1 on page 2. This is the “last mile” of broadband service, with the CMTS typically located in the cable headend or distribution hub. It is targeted at the following data and voice aggregation applications:

Large CATV Hub Sites — DOCSIS multi-service, residential and commercial IP network access over HFC networks maintained by cable television (CATV) multiple service operators (MSOs) needing enhanced integrated data, voice and video in large metropolitan areas.

Small CATV Hub Sites — Smaller hub sites aggregated over metropolitan fiber rings supporting Gigabit Ethernet.

G10 CMTS Introduction 1

G10 CMTS Features and Functions

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Figure 1: Typical CMTS Location


The G10 CMTS provides true multi-services support, including the ability to simultaneously support DOCSIS IP services, VoIP services, and native MPEG transport streams.

Features and Benefits

Innovative features of the G10 CMTS include:

Scalable, high-density chassis that supports from one to eight DOCSIS modules. Each module can be configured for up to four downstream channels at 64 and 256 QAM, and up to 8 upstream channels at QPSK and 16 QAM. This provides a total system capacity of up to 32 downstream channels and 64 upstream channels.

Scaleable and high-density architecture that supports 16,000 service flows per DOCSIS module, up to 128,000 per chassis.

Logical allocation of up to 8 upstream channels to any of the four upstream ports on each DOCSIS Module. This allows channels to be provisioned by the Command Line Interface (CLI), SNMP commands, or a Network Management System without the need for physical node recombining.

Advanced upstream scheduling and a queuing algorithm that efficiently allocates resources to satisfy multiple service flows with the most stringent Quality of Service requirements (Class of Service for DOCSIS 1.0). Per-flow QoS with Diff-Serv ensures end-to-end management of SLAs.

Cable Headendor

Distribution HubInternet

Backbone

PSTN

VideoServers

NetworkManagement

Switch/Router CMTS

Subscribers

Network SideInterface

Hybrid Fiber/CoaxNetwork

Juniper Networks G10 CMTS Operations and Maintenance

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The G10 CMTS delivers the following benefits:

DOCSIS services – DOCSIS 1.0 and EuroDOCSIS 1.0 RF interfaces and protocols

Industry-leading RF performance – Signal-to-Noise Ratio (SNR) performance, efficiency, and configuration flexibility

Advanced diagnostics – spectrum monitoring, historical data

Quality-of-Service – Advanced DOCSIS scheduler for Voice-Over-IP and other applications

Standard network interfaces – Fast Ethernet, Gigabit Ethernet

Line-rate performance

Management interfaces – CLI, Telnet, SNMP, DOCSIS 1.0 MIBs (Management Information Base)

The G10 CMTS is compliant with the following industry specifications:

DOCSIS 1.0

EuroDOCSIS 1.0

Functional Overview

The G10 CMTS is usually connected directly to a Gigabit-class core router that is part of an MSO’s metropolitan core network. It receives network side packet streams originating from the Internet, Media Gateways or video servers, then processes them into DOCSIS-compatible digital signals (MPEG) that are modulated onto an RF carrier for transmission downstream over the HFC network to the subscribers’ cable modems.

Upstream signals consist of PDUs (protocol data units) in data bursts from the cable modems. The G10 CMTS uses advanced scheduling algorithms to optimize the timing of these transmissions. The packets are processed to recover the payload data then routed, as IP packets, to the appropriate destinations through the network side interface.

The G10 CMTS‘s high capacity of up to 32 downstream and 64 upstream channels, and other innovative features, are accomplished by the Broadband Cable Processor ASIC (Application-Specific Integrated Circuit).

Broadband Cable Processor ASIC

The Broadband Cable Processor ASIC provides all-digital processing of the return path. This, plus advanced noise cancellation and equalization algorithms, enables modulation rates beyond QPSK and allows traditionally problematic frequency ranges of the upstream spectrum to be utilized. All-digital processing also accommodates full spectrum analysis by capturing statistics of the upstream band in real time.

The Broadband Cable Processor ASIC incorporates key DOCSIS MAC (Media Access Control) functions such as concatenation, fragmentation, encryption, and decryption. Accelerating these functions in hardware provides a high-performance, scalable CMTS solution that can process thousands of simultaneous DOCSIS service flows.


G10 CMTS Components

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Advanced timing and digital signal processing algorithms allow more efficient use of the RF spectrum resulting in increased channel capacity.

G10 CMTS Components

The primary modules of the G10 CMTS are described below, arranged in the order of downstream data flow. See Figure 2 on page 5 for a graphical depiction of the data flow through the modules in a chassis. The chassis design employs front and rear modules that connect through a midplane. The objective of this design is to place the cable connections to the rear of the unit.

NIC Module – Provides Ethernet switching functionality for upstream and downstream traffic. Houses two Gigabit Ethernet ports with GBICs (Gigabit Interface Converter).

NIC Access Module – Fans out the Ethernet signals to individual 10/100Base-T lines, which route to the HFC Connector Modules.

DOCSIS Module – Performs all data processing functions. Processes IP data into DOCSIS packets. Converts and modulates data for RF transmission. Reverses these processes for upstream data.

HFC Connector Module – Provides cable interfaces for the DOCSIS Module. Contains the Fast Ethernet connectors for network side data, and contains the F-connectors for the HFC cabling.

Chassis Control Module – Provides management interface. Controls redundant protection functions for all modules. Runs the SNMP agent.

CCM Access Module – Provides rear-access to the Chassis Control Module.


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G10 CMTS Management

Figure 2: G10 CMTS Data Flow

G10 CMTS Management

The G10 CMTS supports the following system management applications and tools:

CLI – The Command Line Interface provides the most comprehensive controls and is instrumental for installation, configuration and upgrade tasks.

ServiceGuard™ – This advanced diagnostics system with a Java GUI provides a rendition of a spectrum analyzer for acquiring data on upstream transmission cable performance. It provides a unique ability to detect transmission problems before they become service problems.

NMS – The G10 CMTS can interact with SNMPv2c-based Network Management Systems using DOCSIS 1.0 MIBs and G10 CMTS enterprise MIBs.

NIC

Mo

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NIC

Acc

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Mo

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FC

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Mo

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DO

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Mo

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HybridFiber/Coax

NetworkSide

Interface

Midplane

IP Data

IP D

ata

DOCSIS Data

DOCSIS Data

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ManagementPorts

Management Data

G10 CMTS


G10 CMTS Management

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Chapter 2Command Line Interface Operation
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This chapter provides the Command Line Interface (CLI) procedures used to perform various operational tasks on the G10 CMTS. Appendix B describes the groups and privileges used to implement security and user access in the CLI. For additional details regarding the CLI, refer to the Juniper Networks G10 CMTS CLI Reference.

Management Tasks

This section describes those tasks associated with initializing and managing the G10 CMTS.

Getting Help

To display a list of available commands at the current command level, enter help or a question mark at the command prompt:

G10$root# help↵

G10$root# ?

Notice that a carriage return is not necessary when entering a question mark.

To display a list of valid command parameters, type a question mark after a command:

G10$root# clock ?

adjust - Adjust the system clockset - Set the time and date

To display a list of available editing keystrokes, type help edit:

G10$root# help edit↵

Defining Usernames, Passwords, and Privileges

To define new usernames and assign them passwords and privileges, you must have a group-privilege of ad-rw and you must enter the configure terminal mode. Use the username command as follows:

G10$root# configure terminal↵G10$root(config)# username newuser1 password newpw1↵

Command Line Interface Operation 7

Management Tasks

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To assign IP and read-write group-privilege to newuser1, use the username command as follows:

G10$root(config)# username newuser1 group ip privilege rw↵

To remove newuser1 from the system, use the no username command as follows:

G10$root(config)# no username newuser1↵

Setting the Clock and Date

To set the clock and date, you must have a group-privilege of ad-rw. Use the clock command at the top level as follows:

G10$root# clock set 122200 22 12 2001↵

Sets the clock to 12:22:00 and the date to December 22, 2001.

To adjust the clock, use the clock command at the top level as follows:

G10$root# clock adjust -60↵

Adjusts the clock 60 seconds backwards.

Setting the Hostname

To define a hostname, you must have a group-privilege of ip-rw and you must enter the configure terminal mode. Use the hostname command as follows:

G10$root# configure terminal↵G10$root(config)# hostname CMTS5↵CMTS5$root(config)#

Configuring Banners

To define banners, you must have a group-privilege of ad-rw and you must enter the configure terminal mode.

To define an incoming banner that is displayed when a user logs into the CMTS, use the banner incoming command as follows:

G10$root# configure terminal↵G10$root(config)# banner login "Incoming Banner"↵

The banner displayed will be Incoming Banner:

Copyright (c) 2000-2002 Juniper Networks, Inc.G10 CMTS Release 2.1.0.14

Incoming BannerWed Feb 20 15:05:54 2002

The banner exec, banner login, and banner motd commands can be executed in a similar fashion.


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RF Tasks

RF Tasks

This section describes those tasks associated with the RF functions of the G10 CMTS, such as configuring channels and modulation profiles.

Slot Numbers

The G10 CMTS chassis contains 12 slots that can be populated with modules. The enumeration of the slots and the modules assigned to these slots are illustrated in Figure 3. The slot number is used in conjunction with the interface number to enter the interface cable or interface fastEthernet sub-modes.

Figure 3: G10 CMTS Chassis Slot Assignment

DOCSIS Module

DOCSIS Module

DOCSIS Module

DOCSIS Module

DOCSIS Module

DOCSIS Module

DOCSIS Module

DOCSIS Module

NIC Module

Chassis Control Module


HFC Connector Module








CHASSISTOP VIEW

Midplane

Fro

ntR

ear

NIC Access Module 5

6

4

3

2

1

7

8

9

10

11

12

13

with logical slot numbers

NIC Module

NIC Access Module

CCM Access Module

CCM Access Module

Use the logical slot numbers shown in this illustration for configuration tasks.


RF Tasks

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Cable Interface Assignment

A cable interface is a logical entity that consists of at least one upstream and one downstream port. A cable interface is the same as a MAC domain. The traffic flowing through even numbered cable interfaces (0 and 2) is forwarded through the Ethernet port 0 on the HFC Connector Module, while traffic flowing through odd numbered cable interfaces (1 and 3) is forwarded through the Ethernet port 1 on the HFC Connector Module. This relationship is summarized in Table 1.

Table 1: Cable Interface to Ethernet Port Association

Interface is also used describe the Fast Ethernet ports, which are also configurable. Here, the interface number is the port number.

Port

A port is a physical connector. Use the numerical part of the connector label for the port ID during configuration tasks. Refer to the Figure 4 on page 12 to view the ports on the HFC Connector Module and the Chassis Control Module.

Channel

A channel is a logical entity. There are four downstream channels and 8 upstream channels routed through each HFC Connector Module / DOCSIS Module. Upstream channels can be grouped in any manner and routed through the US ports. Channel IDs are 0 – 7. Downstream channels are assigned one-each to the DS ports. Channel IDs are 0 – 3.

Defaults

Table 2 and Table 3 on page 11 summarize the various associations described above. Note that the upstream channel to upstream port mapping specified in these tables is just the factory default, and can be changed through the cable upstream port command.

Table 2: Cable Interface to Downstream Channel and Port Association

Cable Interface Associated Ethernet Port

0 Eth0

1 Eth1

2 Eth0

3 Eth1

Cable Interface Downstream Channel Downstream Port

0 0 DS 0

1 1 DS 1

2 2 DS 2

3 3 DS 3


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RF Tasks

Table 3: Default Cable Interface to Upstream Channel Association

Cable Interface Upstream Channel Upstream Port

0 0 US 0

1

1 2 US 1

3

2 4 US 2

5

3 6 US 3

7


RF Tasks

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Figure 4: HFC Connector Module and Chassis Control Module

HFC Connector Module Chassis Control Module

Eth0

Eth1

US 3

US 2

US 1

US 0

DS 3

DS 2

DS 1

DS 0

Eth0


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RF Tasks

Configuring a Downstream Channel

The G10 CMTS is shipped with default values assigned to the four downstream channels on a DOCSIS Module. To view these defaults, execute the show running-config command. If these defaults meet your requirements, then you only need to enable a downstream channel to use it.

If you need to change some of the parameters associated with a downstream channel, the procedure in this section will demonstrate how to do so.

The procedure in this section specifies various parameters for downstream channel 0 of slot 1 / interface 0. The available downstream channels on a DOCSIS Module are channels 0–3, which always correspond to downstream ports 0–3, respectively, on the HFC Connector Module. Table 4 provides the valid ranges of all parameters specified in this section.

Table 4: Downstream Channel Parameter Ranges

1. Enter the interface cable sub-mode, specifying slot 1 and interface 0:

G10$root# configure terminal↵G10$root(config)# interface cable 1/0↵

2. Specify a frequency of 453000000 Hz for downstream channel 0:

G10$root(config-if-c1/0)# cable downstream 0 frequency 453000000↵

3. Specify an RF power (in tenths dBmV) of 55 dBmV for downstream channel 0:

G10$root(config-if-c1/0)# cable downstream 0 rf-power 550↵

4. Specify 64qam modulation for downstream channel 0:

G10$root(config-if-c1/0)# cable downstream 0 modulation 64qam↵

5. Specify an interleave depth of 8 for downstream channel 0:

G10$root(config-if-c1/0)# cable downstream 0 interleave-depth 8↵

Care should be taken when modifying any of the parameters associated with a downstream or upstream channel. Incorrect values specified for certain parameters can render a channel inoperative.

Parameter Range

slot 1–4, 10–13

interface 0–3

channel (=port) 0–3

frequency 91000000–857000000

RF power 500 to 610 (tenths dBmV)

modulation 64qam or 256qam

interleave depth 8, 16, 32, 64, 128


RF Tasks

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6. At this point, if you desire to view the downstream channel 0 parameters and status, enter the following command:

G10$root(config-if-c1/0)# cable downstream 0 show↵

7. Enable downstream channel 0:

G10$root(config-if-c1/0)# no cable downstream 0 shutdown↵

Configuring an Upstream Channel

The G10 CMTS is shipped with default values assigned to the eight upstream channels on a DOCSIS Module. To view these defaults, execute the show running-config command. If these defaults meet your requirements, then you only need to enable an upstream channel to use it.

If you need to change some of the parameters associated with an upstream channel, the procedure in this section will demonstrate how to do so.

The procedure in this section specifies various parameters for upstream channel 0 of slot 1 / interface 0. A default modulation profile for channel 0 will be used. The available upstream channels on a DOCSIS Module are channels 0–7, and are assigned to the four upstream ports (0–3) on the HFC Connector Module as defined in Table 3 on page 11. Table 5 provides the valid ranges of all parameters specified in this section.

Table 5: Upstream Channel Parameter Ranges

1. Enter the interface cable sub-mode, specifying slot 1 and interface 0:

G10$root# configure terminal↵G10$root(config)# interface cable 1/0↵


Parameter Range

slot 1–4, 10–13

interface 0–3

channel 0–7

port 0–3

channel width 200000–3200000 Hz

frequency 5000000–42000000 Hz

power-level -10 to +25 dBmV

data-backoff 0–16

range-backoff 0–16

modulation-profile 1–256

minislot-size 2, 4, 8, 16, 32, 64, 128


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RF Tasks

2. Specify a channel width of 200000 Hz for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 channel-width 200000↵

3. Specify a frequency of 5000000 Hz for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 frequency 5000000↵

4. Specify a power level (in dBmV) of 0 dBmV for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 power-level 0↵

5. Specify start and stop data backoff values of 2 and 6, respectively, for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 data-backoff 2 6↵

6. Specify start and stop range backoff values of 3 and 7, respectively, for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 range-backoff 3 7↵

7. Specify a minislot size of 8 for upstream channel 0:

G10$root(config-if-c1/0)# cable upstream 0 minislot-size 8↵

8. At this point, if you desire to view the upstream channel 0 parameters and status, enter the following command:

G10$root(config-if-c1/0)# cable upstream 0 show↵

9. Enable upstream channel 0:

G10$root(config-if-c1/0)# no cable upstream 0 shutdown↵

Configuring an Upstream Modulation Profile

DOCSIS specifies different burst types, each associated with an Interval Usage Code (IUC), for upstream transmissions, such as request, initial, station, short, and long (refer to Table 6 on page 16). During a burst transmission, a CM must use the burst parameters assigned for that particular type of burst. These parameters are defined in an upstream modulation profile (refer to Table 7 on page 16). Upstream modulation profiles are assigned on a per upstream channel basis.


RF Tasks

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16

Table 6: Interval Usage Codes

Table 7: Upstream Modulation Profile Parameters

Specifying the upstream modulation profile parameters is accomplished by using the cable modulation-profile command. The order of the parameters specified in the command is given from top to bottom in the Parameter column of Table 7.

The cable upstream modulation-profile command is used to assign an upstream modulation profile to an upstream channel.

IUC Description

request An upstream interval in which requests may be made for bandwidth for upstream data transmission

initial An interval in which new stations (cable modems) may join the network

station An interval in which stations are expected to perform some aspect of routine network maintenance, such as ranging or power adjustment

short An interval in which a CM transmits one or more upstream Protocol Data Units (PDUs). The interval for a short interval is less than or equal to the Maximum Burst Size defined in the short profile.

long An interval in which a CM transmits one or more upstream Protocol Data Units (PDUs). The number of mini-slots in the interval is larger than the maximum for short interval transmissions.

Parameter Range Description

FEC T bytes 0–10 The number of codeword parity bytes is 2*T (0 implies no FEC—forward error correction). T is the number of bytes that can be corrected per FEC codeword.

FEC K bytes 16–253 Codeword information bytes (Not used if no FEC, T=0)

maxburst size 0–255 The maximum number of mini-slots that can be transmitted during this burst type

guard time 0–255 Number of symbol times which must follow the end of this burst

modulation 16qamqpsk

Upstream modulation type

scrambler scrambler Determines if the scrambler is used

scramber seed 0–7FFF The 15-bit scrambler seed value

diff encoding diffno-diff

Determines if differential encoding is used

preamble length 0,2,4,...1024 – QPSK0,4,8,...1024 – 16QAM

Defines the length of the preamble in bits

shortened last codeword fixedshortened

Determines whether the last codeword is shortened or not.


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RF Tasks

Two of the IUCs—short and long—are used for the transmission of data to the CMTS. The burst parameters associated with these two particular IUCs significantly affect the efficiency of the upstream channel on which the CMs are transmitting, particularly the following parameters—FEC T bytes, FEC K bytes, modulation, preamble length, and shortened last codeword. In an environment with relatively low noise levels, an operator might specify the smallest number of FEC T bytes (or even turn off the FEC) and the largest number of FEC K bytes in order to minimize the overhead used for error checking. Using a modulation type of 16QAM, as opposed to QPSK, would approximately double the data bandwidth. Minimizing the preamble length and enabling shortened last codeword also increases the channel efficiency by reducing the amount of bits in a packet that are not used as part of the data payload.

However, in practice, an HFC plant may have higher levels of noise attributed to Additive White Gaussian Noise, impulse noise, and narrowband ingress. Therefore, the burst parameters must be specified so that CMs can achieve a balance between maximizing the channel bandwidth, and successfully operating within a potentially noisy upstream environment.

The G10 CMTS is shipped from the factory with eight pre-defined modulation profiles. Three of these eight profiles—Profiles 1, 2, and 3—are recommended for your usage (refer to Table 8). The remaining five profiles—Profiles 4–8—are defined for laboratory purposes and are not suitable for real-world environments. To display a particular modulation profile, use the cable modulation-profile show command.

The values within Table 8 are subject to change.


RF Tasks

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18

Table 8: Modulation Profiles 1, 2, and 3

Profile 1 is defined for full QPSK operation (QPSK modulation is used in all interval types). Profile 3 is defined for mixed 16QAM and QPSK operation in which 16QAM is used for short and long intervals, and QPSK is used for all other intervals. Profile 2 should be used in place of Profile 3 if it is known that the CMs on this channel do not transmit at the same power level for 16QAM and QPSK bursts.

The following procedure describes how to create a modulation profile and assign it to an upstream channel. In this example, a modulation profile ID of 15 (out of 256) is arbitrarily chosen. Table 9 provides the ten modulation profile parameters and the specific values used in the following procedure for each of the burst intervals.

Profile IUCFEC T bytes

FEC K bytes

maxburstsize guardtime modulation scrambler

scramblerseed

diffencoding

preamblelength

shortenedlastcodeword

1

request 0 16 0 6 qpsk scrambler 1 diff 68 fixed

initial 3 34 0 5 qpsk scrambler 1 diff 52 fixed

station 3 34 0 5 qpsk scrambler 1 diff 52 fixed

short 5 75 8 5 qpsk scrambler 1 diff 32 shortened

long 8 220 0 5 qpsk scrambler 1 diff 32 shortened

2

request 0 16 0 5 16qam scrambler 1 diff 188 fixed

initial 3 34 0 5 16qam scrambler 1 diff 104 fixed

station 3 34 0 5 16qam scrambler 1 diff 104 fixed

short 5 75 8 5 16qam scrambler 1 diff 64 shortened

long 8 220 0 5 16qam scrambler 1 diff 64 shortened

3




short 5 75 8 5 16qam scrambler 1 diff 64 shortened

long 8 220 0 5 16qam scrambler 1 diff 64 shortened



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RF Tasks

Table 9: Modulation Profile Interval Parameters

1. Enter the configure terminal mode:

G10$root# configure terminal↵

2. Specify the parameters for a request interval for modulation profile 15:

G10$root(config)# cable modulation-profile 15 request 0 16 0 6 qpsk scrambler 1 diff 68 fixed↵

3. Specify the parameters for an initial maintenance interval for modulation profile 15:

G10$root(config)# cable modulation-profile 15 initial 3 34 0 5 qpsk scrambler 1 diff 52 fixed↵

4. Specify the parameters for a station maintenance interval for modulation profile 15:

G10$root(config)# cable modulation-profile 15 station 3 34 0 5 qpsk scrambler 1 diff 52 fixed↵

5. Specify the parameters for a short data grant interval for modulation profile 15:

G10$root(config)# cable modulation-profile 15 short 3 40 8 5 qpsk scrambler 1 diff 36 shortened↵

6. Specify the parameters for a long data grant interval for modulation profile 15:

G10$root(config)# cable modulation-profile 15 long 3 100 0 5 qpsk scrambler 1 diff 36 shortened↵

7. Assign a modulation profile of 15 for upstream channel 0:

G10$root(config)# interface cable 1/0↵G10$root(config-if-c1/0)# cable upstream 0 modulation-profile 15↵

8. View modulation profile 15:

G10$root(config-if-c1/0)# exit↵G10$root(config)# cable modulation-profile 15 show↵

ModId IUC prelen seed mod dif fec data/fec brst guard lstcw scrmb 1 request(1) 68 0x0001 QPSK Y 0 16 0 6 2 Y 1 reqdata(2) 68 0x0001 QPSK Y 3 40 8 6 2 Y 1 initial(3) 52 0x0001 QPSK Y 3 34 0 5 2 Y 1 station(4) 52 0x0001 QPSK Y 3 34 0 5 2 Y 1 short(5) 36 0x0001 QPSK Y 3 40 8 5 1 Y 1 long(6) 36 0x0001 QPSK Y 3 100 0 5 1 Y

IUCFEC T bytes

FEC K bytes

maxburstsize guardtime modulation scrambler

scramblerseed

diffencoding

preamblelength

shortenedlastcodeword




short 3 40 8 5 qpsk scrambler 1 diff 36 shortened

long 3 100 0 5 qpsk scrambler 1 diff 36 shortened


NSI Tasks

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20

Enabling Upstream Multicast and Broadcast

To enable the forwarding of all upstream multicast packets, you must have a group-privilege of ip-rw and you must enter the interface cable sub-mode. Use the cable ip-multicast-echo command as follows:

G10$root# configure terminal↵G10$root(config)# interface cable 4/1↵G10$root(config-if-c4/1)# cable ip-multicast-echo↵

Forward all upstream IP multicast packets on slot 4 / interface 1.

To enable the forwarding of all upstream broadcast packets, you must have a group-privilege of ip-rw and you must enter the interface cable sub-mode. Use the cable ip-broadcast-echo command as follows:

G10$root(config-if-c4/1)# cable ip-broadcast-echo↵

Forward all upstream IP broadcast packets on slot 4 / interface 1.

NSI Tasks

This section describes those tasks associated with the Network Side Interface (NSI) functions of the G10 CMTS, such as configuring FastEthernet interfaces.

Configuring a Fast Ethernet Interface

The G10 CMTS is shipped with default values assigned to the Fast Ethernet interfaces. To view these defaults, execute the show running-config command. These defaults generally meet a user’s requirements and should not have to be modified.

To configure and enable a Fast Ethernet interface, you must have a group-privilege of ip-rw and you must enter the interface fastEthernet sub-mode.

The procedure in this section enables the two Fast Ethernet interfaces on the DOCSIS Module/HFC Connector Module pair in slot 1:

1. Enter the interface fastEthernet sub-mode, specifying slot 1 and interface 0 for Fast Ethernet port 0:

G10$root# configure terminal↵G10$root(config)# interface fastEthernet 1/0↵2. Enable Fast Ethernet port 0:

G10$root(config-if-f1/0)# no shutdown↵

3. Exit back to the configure terminal mode:

G10$root(config-if-f1/0)# exit↵


G10$root(config)# interface fastEthernet 1/1↵


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NSI Tasks

5. Enable Fast Ethernet port 1:


A management interface is established by using the Fast Ethernet port labeled “Eth0” on the Chassis Control Module. The following procedure describes how to configure this interface:

6. Exit back to the configure terminal mode:

G10$root(config-if-f1/1)# exit↵

7. Assign an IP address of 192.177.122.3 for the default gateway for the management interface:

G10$root(config)# ip default-gateway 192.177.122.3 management↵


G10$root(config)# interface fastEthernet 6/0↵

9. Assign an IP address of 192.177.122.1 and a subnet mask of 255.255.255.0 for slot 6/ interface 0:

G10$root(config-if-f6/0)# ip address 192.177.122.1 255.255.255.0↵

10. Enable Fast Ethernet port 0:


DHCP Server Parameters

The CLI is used to configure the CMTS with various parameters associated with the Dynamic Host Control Protocol (DHCP). The cable helper-address command is used to specify the IP address of the DHCP server. If the DHCP server is not on a directly-attached subnet to the Fast Ethernet port to which the DHCP traffic is being forwarded, then the next-hop parameter must also be specified. To use the cable helper-address command, you must have a group-privilege of ip-rw and you must enter the interface cable sub-mode.

The following example specifies an IP address of 192.71.25.108 for the DHCP server, and assumes that the DHCP server is not attached to the Fast Ethernet subnet to which the DHCP traffic is being forwarded. In this case, the next-hop parameter (172.168.10.1) must be specified. The absence of the optional parameters cable-modem and host implies that the specified DHCP server is used for both cable modems and CPE devices.

G10$root# configure terminal↵G10$root(config)# interface cable 4/1↵G10$root(config-if-c4/1)# cable helper-address 192.71.25.108 172.168.10.1↵


NSI Tasks

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22

The cable dhcp-giaddr CLI command specifies both the IP address for the associated cable interface as well as the IP address to be used as the GIADDR when relaying DHCP requests. The G10 CMTS responds to the ARP requests for this IP address. Assume the cable modems are supposed to get the IP addresses from the 172.168.10.0 subnet and the CPE devices are supposed to get the IP addresses from the 172.168.11.0 subnet. The IP address for the dhcp-giaddr for CMs must be on the same subnet as the CMs. Similarly, the dhcp-giaddr for CPE devices must be on the same subnet as the CPE devices. In this example, 172.168.10.2 will be selected for the dhcp-giaddr for CMs, and 172.168.11.2 will be selected for the dhcp-giaddr for CPE devices.

G10$root(config-if-c4/1)# cable dhcp-giaddr 172.168.10.2 cable-modem↵G10$root(config-if-c4/1)# cable dhcp-giaddr 172.168.11.2 host↵

To enable the CMTS to insert DHCP relay information in BOOTREQUEST messages forwarded by a CM or CPE to DHCP servers, you must have a group-privilege of ip-rw and you must enter the interface cable sub-mode. Use the cable relay-agent-option command as follows:

G10$root(config-if-c4/1)# cable relay-agent-option↵

Shared Secret

To specify a shared secret, which is an authentication string that is shared between a server that provides a cable modem’s configuration file and the CMTS, you must have a group-privilege of rf-rw and you must enter the configure terminal mode. Use the cable shared-secret command as follows:

G10$root# configure terminal↵G10$root(config)# cable shared-secret mysecret↵

The shared secret authentication string is “mysecret.”

SNMP Server Parameters

To specify the SNMP password community string and set the access privilege, you must have a group-privilege of ip-rw and you must enter the configure terminal mode. Use the snmp-server community command as follows:

G10$root(config)# snmp-server community server_A rw↵

Establishes “server_A” as the SNMP password and sets read/write privileges.

G10$root(config)# snmp-server community server_A ro↵

Establishes “server_A” as the SNMP password and sets read-only privileges.

To specify the destination host(s) that will receive SNMP traps, you must have a group-privilege of ip-rw and you must enter the configure terminal mode. If a port number is not specified, it will default to 162. Use the snmp-server host command as follows:

G10$root(config)# snmp-server host 205.15.128.132 version 2c port 168↵

Specify an IP address of 205.15.128.132 for the SNMP server. The SNMP version that will be used is 2c. SNMP traps will be sent to UDP port 168.


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NSI Tasks

To specify the IP address of a domain name system (DNS) server, you must have a group-privilege of ip-rw and you must enter the configure terminal mode. Use the ip name-server command as follows:

Domain Name Server Address

G10$root(config)# ip name-server 192.16.90.1↵G10$root(config)# ip name-server 192.16.90.2↵

Adds the DNS servers at addresses 192.16.90.1 and192.16.90.2. The CMTS will then consult these addresses, in that order, when resolving a host name.

File and Directory Management

Displaying and changing directories can be performed at any group level with read-only access.

To display a directory, use either the dir command or the ls command as follows:

G10$root> dir /home↵G10$root> ls /home↵

Each of these two commands displays the contents of the directory home.

To display the current directory, use the pwd command as follows:

G10$root> pwd↵To change the current directory, use the cd command as follows:

G10$root> cd temp↵

The command prompt location is changed to the temp directory using a relative path. The temp directory must be under the current location.

G10$root> cd/home/temp↵

The command prompt location is changed to the temp directory using an absolute path.

Creating or deleting a directory can be performed at any group level, but you must have read-write privileges.

Use the mkdir command to create a new directory as follows:

G10$root# cd /samples/data↵G10$root# mkdir logs↵G10$root# cd /logs↵

Creates a new directory named logs in the path sample/data.

Use the rmdir command to delete a directory as follows:

G10$root# rmdir /logs↵

Deletes the directory named logs in the current path.


NSI Tasks

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24

Viewing and Saving Running Configuration

Viewing and saving configuration files can be performed at any group level with read-write access. To view the current configuration of the G10 CMTS, execute the following command:

G10$root# show running-config↵

To save the current configuration of the G10 CMTS, execute the following command. Upon booting up, the system uses the startup-config file to set the configuration:

G10$root# copy running-config startup-config↵

Pinging and Trace Routing

Pinging an IP address can be performed at any group level with read-only access. Use the ping command at the top level as follows:

G10$root> ping 100.205.50.150↵

Verifies the connection between the CMTS and the device at IP address 100.205.50.150.

To trace a connection to a specified IP address, you must have a group-privilege of ip-ro. Use the traceroute command at the top level as follows:

G10$root> traceroute 172.164.70.13↵


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Chapter 3RF Measurements
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This chapter provides the procedures for measuring the downstream and upstream RF signals of a DOCSIS Module using a spectrum analyzer. These procedures can be followed immediately after the initial installation and configuration of the G10 CMTS to ensure the system is configured and operating properly. In addition, these procedures can assist with the diagnosis of RF issues that are detected by spectrum monitoring applications such as ServiceGuard™.

The following procedures assume the use of a Hewlett Packard HP8591C CATV Analyzer, but any equivalent spectrum analyzer will suffice.

Downstream RF Measurement in CATV Mode

This section describes the procedure for measuring the downstream signal power from the G10 CMTS using CATV mode on the HP8591C CATV Analyzer. If your spectrum analyzer does not support CATV mode, you can use the SPECTRUM ANALYZER mode as described in “Downstream RF Measurement in Spectrum Analyzer Mode” on page 27.

1. Connect the spectrum analyzer to a cable within the plant that carries the downstream signal you are measuring. The signal originates from one of the downstream ports of the HFC Connector Module (“DS 0” through “DS 3”).

2. View (or set) the output RF power level of the specific channel to be measured. In this example, the output RF power level for channel 0 on slot 1 / interface 0 is set to 61 dBmV. The power specified in the cable downstream rf-power command can be viewed by executing the show running-config command, or alternatively by using SNMP.


continued...interface

cable 1/0 cable downstream 0 channel-width 6000000 cable downstream 0 frequency 531000000 cable downstream 0 interleave-depth 8 cable downstream 0 modulation 64qam cable downstream 0 rf-power 610 no cable downstream 0 shutdown

continued...

This command displays the current configuration. Look for the channel downstream <channel> rf-power <power-level> output to determine the power level specified for the downstream channel. The power level is displayed in tenths of dBmV.

RF Measurements 25

Downstream RF Measurement in CATV Mode

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26

To set the output RF power level, use the cable downstream rf-power command as follows (the power level is specified in tenths of dBmV):

G10$root# configure terminal↵G10$root(config)# interface cable 1/0↵G10$root(config-if-c1/0)# cable downstream 0 rf-power 610

3. Press the MODE key and set the spectrum analyzer to CABLE TV ANALYZER mode.

4. Select CHANNEL MEAS (channel measurement) and enter the desired channel number. In this example, channel 75 is selected, which corresponds to a center frequency of 531 MHz.

5. Navigate to the third menu on the screen and select DIGITAL POWER. The spectrum analyzer display should be similar to the display in Figure 5.

6. Ensure that the DIGITAL CHANNEL POWER shown at the bottom of the display is approximately equal to the set downstream power level, minus any attenuation between the HFC Connector Module downstream port and the point at which your measurement is taken in the cable plant. In this example, the attentuation between the CMTS and the measurement point was approximately 13 dB. Therefore, the expected measured value should be approximately 48 dBmV.

Figure 5: Downstream RF Signal (CATV Mode)


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Downstream RF Measurement in Spectrum Analyzer Mode

Downstream RF Measurement in Spectrum Analyzer Mode

This section describes the procedure for measuring the downstream signal power from the G10 CMTS using the spectrum analyzer mode on the HP8591C CATV Analyzer.

1. Connect the spectrum analyzer to a cable within the plant that carries the downstream signal you are measuring. The signal originates from one of the downstream ports of the HFC Connector Module (“DS 0” through “DS 3”).

2. View (or set) the output RF power level of the specific channel to be measured. In this example, the output RF power level for channel 0 on slot 1 / interface 0 is set to 61 dBmV. The power specified in the cable downstream rf-power command can be view by executing the show running-config command, or alternatively by using SNMP.


continued...interface

cable 1/0 cable downstream 0 channel-width 6000000 cable downstream 0 frequency 531000000 cable downstream 0 interleave-depth 8 cable downstream 0 modulation 64qam cable downstream 0 rf-power 610 no cable downstream 0 shutdown

continued...

This command displays the current configuration. Look for the channel downstream <channel> rf-power <power-level> output to determine the power level specified for the downstream channel. The power level is displayed in tenths of dBmV.

To set the output RF power level, use the cable downstream rf-power command as follows (the power level is specified in tenths of dBmV):

G10$root# configure terminal↵G10$root(config)# interface cable 1/0↵G10$root(config-if-c1/0)# cable downstream 0 rf-power 610↵

3. Press the MODE key and set the spectrum analyzer to SPECTRUM ANALYZER mode.

4. Press the FREQUENCY key and enter the desired frequency. In this example, 531 MHz is entered.

5. Press the SPAN key and enter 6 MHz.

6. Press the BW key and turn video averaging on by selecting VID AVG ON. The default number of averages is 100. The number of averages can be changed by using the numeric keypad.

7. Press the MKR FCTN key (marker function) and select MK NOISE ON. This sets the spectrum analyzer to read out the power bandwidth, normalized to 1 Hz. The spectrum analyzer display should be similar to the display in Figure 6 on page 28.

RF Measurements 27

Upstream RF Measurement

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28

8. The power shown on the display in Figure 6—shown in two places, on the top/right and middle/left—is –19.12 dBmV, at 1 Hz. In order to obtain the power in the 6 MHz channel, a correction factor is required. This correction factor equals 10 log(ChannelBW/measurementBW). In this case, 10 log (6x10^6/1) equals 67.78 dB. Therefore, the actual downstream channel power equals -19.12+67.78, which equals 48.66 dBmV. Ensure that this power value is approximately equal to the set downstream power level, minus any attenuation between the HFC Connector Module downstream port and the point at which your measurement is taken in the cable plant. In this example, the attentuation between the CMTS and the measurement point was approximately 13 dB. Therefore, the expected measured value should be approximately 48 dBmV.

Figure 6: Downstream RF Signal (Spectrum Analyzer Mode)


This section describes the procedure for measuring an upstream signal to the G10 CMTS using zero span mode on the HP8591C CATV Analyzer.

1. Connect the spectrum analyzer to a cable within the plant that carries the upstream signal(s) you are measuring. The signals are received on one of the upstream ports of the HFC Connector Module (“US 0” through “US 3”).

DOCSIS specifies that cable modems use TDMA (Time Division Multiple Access) for upstream transmissions, which means that cable modems are not continuously transmitting. In order to facilitate the triggering and capture of upstream signals, the cable modems should be transmitting long packets as often as possible.


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2. Press the FREQ key and enter the center frequency that corresponds to the upstream frequency you are measuring. In this example, the upstream frequency is 9 MHz. The upstream channel frequency can be viewed by executing the show running-config CLI command, or alternatively by using SNMP.


continued...cable upstream 0 channel-width 1600000cable upstream 0 data-backoff 3 10cable upstream 0 frequency 9000000cable upstream 0 minislot-size 8

continued...

This command displays the current configuration. Look for the channel upstream <channel> frequency <frequency> output to determine the frequency specified for the upstream channel.

3. Press the SPAN key and enter 0 MHz (or select ZERO SPAN). This sets the spectrum analyzer to zero span mode, where signals will be displayed in the time domain.

4. Press the BW key (Bandwidth), select RES BW MAN (Resolution Bandwidth Manual), and enter 3 MHz.

5. While in the BW key menu, select VID BW MAN (Video Bandwidth Manual), and enter 3 MHz.

6. Press the AMPLITUDE key, select ATTEN MAN (Attenuation Manual), and enter 0 dB. This removes all internal spectrum analyzer attenuation.

7. While still in the AMPLITUDE screen, select REF LVL (Reference Level), and enter a value slightly greater than the maximum power level you are expecting. The reference level is the power represented by the top graticule line in the display. In this example, the reference level is set to 5 dBmV.

8. Select SCALE and adjust the scale so that the signal spans the entire Y-axis of the display.

9. Press the TRIG key (Trigger), select VIDEO, and adjust the trigger line to within one graticule of the peak of the signal.

10. Press the SWEEP key, select SWP TIME MAN (Sweep Time Manual), and set the sweep time to a value in the range of 80–100 µs.

11. Press the SGL SWP key (Single Sweep) repeatedly until the spectrum analyzer display is similar to the display in Figure 7 on page 30. The first three graticule columns represent the upstream burst transmission of a single cable modem, including the preamble.

12. Press the MKR (Marker) key and adjust the marker to a position on the signal that represents the median power level of the signal. In Figure 7, the marker is approximately positioned at a median level of 0.65 dBmV. Ensure that this power level is equal to the expected receive power level of the CMTS plus any attenuation between the CMTS and the point of measurement. The upstream channel power level can be viewed by executing the show running-config CLI command:

RF Measurements 29


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30


continued...cable upstream 0 port 0cable upstream 0 power-level 0cable upstream 0 range-backoff 1 5

continued...

This command displays the current configuration. Look for the channel upstream <channel> power-level <power-level> output to determine the power level specified for the upstream channel.

Figure 7: Single Upstream Burst

Figure 8 on page 31 represents the spectrum analyzer display of multiple upstream bursts. This display was produced by following the previous procedure with the following modifications: the reference level in step 7 was set to 10 dBmV, and the sweep time in step 10 was set to 20 msec.


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Figure 8: Multiple Upstream Bursts

RF Measurements 31


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Appendix AAgency Certifications
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This appendix lists agency compliance and certifications for the G10 CMTS.

UL 60950

FCC Part 15, Class A

Industry Canada ICES–003, Class A

This equipment is intended only for installation in a restricted access location within a building.

This equipment is intended for indoor use only.

This equipment does not have a direct copper connection to the outside plant.

Removal of power supplies or cards will result in access to hazardous energy.

Each power cord must be connected to an independent branch circuit.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

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34

••

Appendix BSecurity
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This appendix describes the groups and privileges used to implement security and user access in the Command Line Interface (CLI).

Access to CLI commands is granted to users based on their assigned group and privilege. This matrix is shown in Table 10.

Table 10: Group/Privilege Matrix

Groups

Groups are associated with commands in the following manner:

IP – Those commands that relate to network-side functions. Examples are Ethernet port and IP routing configuration.

RF – Those commands that relate to hybrid fiber/coax-side functions. Examples are interface cable configuration and modulation profile set-up.

AD – Those commands limited to basic administration functions.

Privileges

Each command in the CLI is associated with all the privileges that may be needed to operate that command as follows:

RW – Read-write allows a user to obtain a display from a command, and to input parameters to the command.

RD – Read-debug allows access to the series of debug commands. It also limits access to some of the show commands.

RW (Read-Write) RD (Read-Debug) RO (Read-Only)Group

IP (Network Side) ip-rw ip-rd ip-ro

RF (HFC Side) rf-rw rf-rd rf-ro

AD (Administration) ad-rw ad-rd ad-ro

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36

RO – Read-only allows a user to obtain a display from a command.

The three categories of privileges are hierarchical:

Commands

Each command in the CLI hierarchy of commands has one or more group-privilege associated with it. You cannot change this association. See the command summary in the Juniper Networks G10 CMTS CLI Reference for associations, which are shown with abbreviations such as ip-ro, rf-rw and so forth.

Users

Each user is assigned to at least one group-privilege with this command:

username <name> group {ad|ip|rf} privilege {rw|ro|rd}

Users may be assigned to multiple group-privileges.

root is a username built in to the G10 CMTS that is assigned to all group-privileges.

This Level Can Also Access This Level

RW RD, RO

RD RO

RO —


••

Appendix CField Replaceable Units
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This appendix lists the complete set of field replaceable units (FRU) within the G10 CMTS. A FRU can be ordered as a separate unit for replacement into the CMTS, or for purposes of stocking spare parts.

Following is an alphabetical list of G10 CMTS FRUs. Refer to the Juniper Networks G10 CMTS Installation and Configuration manual for a description of each FRU.

AC Power Supply

AC Power Transition Module

Air Management Module

Air Management Panel

CCM Access Module

Chassis


DOCSIS Module

DC Power Supply

DC Power Transition Module

Front Fan Tray

GBIC Module


NIC Module

Network Access Module

Power Supply Filler Panel

Rear Fan Tray

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38

••

Appendix DEIA Channel Plans
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Table 11 lists the EIA (Electronic Industries Association) standard, IRC (Incrementally Related Carrier), and HRC (Harmonically Related Carrier) frequency plans.

The frequencies in Table 11 represent the video center frequencies. Add 1.75 MHz to calculate the DOCSIS center frequency.

Table 11: EIA Channel Plan

Channel STD IRC HRC

T-7 7.0000

T-8 13.0000

T-9 19.0000

T-10 25.0000

T-11 31.0000

T-12 37.0000

T-13 43.0000

1 / A-8 73.2625 72.0036

2 55.2500 55.2625 54.0027

3 61.2500 61.2625 60.0030

4 67.2500 67.2625 66.0033

5 / A-7 77.2500 79.2625 78.0039

6 / A-6 83.2500 85.2625 84.0042

7 175.2500 175.2625 174.0087

8 181.2500 181.2625 180.0090

9 187.2500 187.2625 186.0093

10 193.2500 193.2625 192.0096

11 199.2500 199.2625 198.0099

12 205.2500 205.2625 204.0102

13 211.2500 211.2625 210.0105

14 / A 121.2625 121.2625 120.0060

15 / B 127.2625 127.2625 126.0063

16 / C 133.2625 133.2625 132.0066

17 / D 139.2500 139.2625 138.0069

18 / E 145.2500 145.2625 144.0072

19 / F 151.2500 151.2625 150.0075

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40

20 / G 157.2500 157.2625 156.0078

21 / H 163.2500 163.2625 162.0081

22 / I 169.2500 169.2625 168.0084

23 / J 217.2500 217.2625 216.0108

24 / K 223.2500 223.2625 222.0111

25 / L 229.2625 229.2625 228.0114

26 / M 235.2625 235.2625 234.0117

27 / N 241.2625 241.2625 240.0120

28 / O 247.2625 247.2625 246.0123

29 / P 253.2625 253.2625 252.0126

30 / Q 259.2625 259.2625 258.0129

31 / R 265.2625 265.2625 264.0132

32 / S 271.2625 271.2625 270.0135

33 / T 277.2625 277.2625 276.0138

34 / U 283.2625 283.2625 282.0141

35 / V 289.2625 289.2625 288.0144

36 / W 295.2625 295.2625 294.0147

37 / AA 301.2625 301.2625 300.0150

38 / BB 307.2625 307.2625 306.0153

39 / CC 313.2625 313.2625 312.0156

40 / DD 319.2625 319.2625 318.0159

41 / EE 325.2625 325.2625 324.0162

42 / FF 331.2750 331.2750 330.0165

43 / GG 337.2625 337.2625 336.0168

44 / HH 343.2625 343.2625 342.0171

45 / II 349.2625 349.2625 348.0174

46 / JJ 355.2625 355.2625 354.0177

47 / KK 361.2625 361.2625 360.0180

48 / LL 367.2625 367.2625 366.0183

49 / MM 373.2625 373.2625 372.0186

50 / NN 379.2625 379.2625 378.0189

51 / OO 385.2625 385.2625 384.0192

52 / PP 391.2625 391.2625 390.0195

53 / QQ 397.2625 397.2625 396.0198

54 / RR 403.2500 403.2625 402.0201

55 / SS 409.2500 409.2625 408.0204

56 / TT 415.2500 415.2625 414.0207

57 / UU 421.2500 421.2625 420.0210

58 / VV 427.2500 427.2625 426.0213

59 / WW 433.2500 433.2625 432.0216

60 / XX 439.2500 439.2625 438.0219

61 / YY 445.2500 445.2625 444.0222

62 / ZZ 451.2500 451.2625 450.0225

Channel STD IRC HRC


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63 / AAA 457.2500 457.2625 456.0228

64 / BBB 463.2500 463.2625 462.0231

65 / CCC 469.2500 469.2625 468.0234

66 / DDD 475.2500 475.2625 474.0237

67 / EEE 481.2500 481.2625 480.0240

68 / FFF 487.2500 487.2625 486.0243

69 / GGG 493.2500 493.2625 492.0246

70 / HHH 499.2500 499.2625 498.0249

71 / III 505.2500 505.2625 504.0252

72 / JJJ 511.2500 511.2625 510.0255

73 / KKK 517.2500 517.2625 516.0258

74 / LLL 523.2500 523.2625 522.0261

75 / MMM 529.2500 529.2625 528.0264

76 / NNN 535.2500 535.2625 534.0267

77 / OOO 541.2500 541.2625 540.0270

78 / PPP 547.2500 547.2625 546.0273

79 / QQQ 553.2500 553.2625 552.0276

80 / RRR 559.2500 559.2625 558.0279

81 / SSS 565.2500 565.2625 564.0282

82 / TTT 571.2500 571.2625 570.0285

83 / UUU 577.2500 577.2625 576.0288

84 / VVV 583.2500 583.2625 582.0291

85 / WWW 589.2500 589.2625 588.0294

86 / XXX 595.2500 595.2625 594.0297

87 / YYY 601.2500 601.2625 600.0300

88 / ZZZ 607.2500 607.2625 606.0303

89 613.2500 613.2625 612.0306

90 619.2500 619.2625 618.0309

91 625.2500 625.2625 624.0312

92 631.2500 631.2625 630.0315

93 637.2500 637.2625 636.0318

94 643.2500 643.2625 642.0321

95 / A-5 91.2500 91.2625 90.0045

96 / A-4 97.2500 97.2625 96.0048

97 / A-3 103.2500 103.2625 102.0051

98 / A-2 109.2750 109.2750 108.0054

99 / A-1 115.2750 115.2750 114.0057

100 649.2500 649.2625 648.0324

101 655.2500 655.2625 654.0327

102 661.2500 661.2625 660.0330

103 667.2500 667.2625 666.0333

104 673.2500 673.2625 672.0336

105 679.2500 679.2625 678.0339

Channel STD IRC HRC

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42

106 685.2500 685.2625 684.0342

107 691.2500 691.2625 690.0345

108 697.2500 697.2625 696.0348

109 703.2500 703.2625 702.0351

110 709.2500 709.2625 708.0354

111 715.2500 715.2625 714.0357

112 721.2500 721.2625 720.0360

113 727.2500 727.2625 726.0363

114 733.2500 733.2625 732.0366

115 739.2500 739.2625 738.0369

116 745.2500 745.2625 744.0372

117 751.2500 751.2625 750.0375

118 757.2500 757.2625 756.0378

119 763.2500 763.2625 762.0381

120 769.2500 769.2625 768.0384

121 775.2500 775.2625 774.0387

122 781.2500 781.2625 780.0390

123 787.2500 787.2625 786.0393

124 793.2500 793.2625 792.0396

125 799.2500 799.2625 798.0399

126 805.2500 805.2625 804.0402

127 811.2500 811.2625 810.0405

128 817.2500 817.2625 816.0408

129 823.2500 823.2625 822.0411

130 829.2500 829.2625 828.0414

131 835.2500 835.2625 834.0417

132 841.2500 841.2625 840.0420

133 847.2500 847.2625 846.0423

134 853.2500 853.2625 852.0426

135 859.2500 859.2625 858.0429

136 865.2500 865.2625 864.0432

137 871.2500 871.2625 870.0435

138 877.2500 877.2625 876.0438

139 883.2500 883.2625 882.0441

140 889.2500 889.2625 888.0444

141 895.2500 895.2625 894.0447

142 901.2500 901.2625 900.0450

143 907.2500 907.2625 906.0453

144 913.2500 913.2625 912.0456

145 919.2500 919.2625 918.0459

146 925.2500 925.2625 924.0462

147 931.2500 931.2625 930.0465

148 937.2500 937.2625 936.0468

Channel STD IRC HRC


••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

149 943.2500 943.2625 942.0471

150 949.2500 949.2625 948.0474

151 955.2500 955.2625 954.0477

152 961.2500 961.2625 960.0480

153 967.2500 967.2625 966.0483

154 973.2500 973.2625 972.0486

155 979.2500 979.2625 978.0489

156 985.2500 985.2625 984.0492

157 991.2500 991.2625 990.0495

158 997.2500 997.2625 996.0498

159 1003.250 1003.2625 1002.0501

Channel STD IRC HRC

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44

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45

IndexIndex

Numerics16QAM..................................................................17, 18

Aagency certifications....................................................33

Bbanners .........................................................................8BOOTREQUEST...........................................................22Broadband Cable Processor ASIC ..................................3broadcast packets........................................................20

Ccable interface.............................................................10CATV mode .................................................................25certifications................................................................33channel .......................................................................10

downstream.........................................................13frequency.............................................................13upstream..............................................................14width....................................................................15

channels ........................................................................2Chassis Control Module ...............................................10clock..............................................................................8community string ........................................................22configuration file

saving...................................................................24viewing ................................................................24

correction factor ..........................................................28CPE .............................................................................22

Ddata backoff ................................................................15date ...............................................................................8default gateway ...........................................................21DHCP ..........................................................................21DHCP relay..................................................................22directory

changing ..............................................................23

creating ................................................................23deleting ................................................................23displaying.............................................................23

DNS .............................................................................23DOCSIS Module .........................................10, 13, 14, 20document conventions ..................................................xDomain Name Server ..................................................23downstream ..........................................................13, 14

FFast Ethernet .........................................................10, 20FEC..............................................................................16forward error correction ..............................................16

GG10 CMTSfeatures ..................................................................2functional overview ................................................1management ..........................................................5

GIADDR.......................................................................22group-privilege...............................................................8guard time...................................................................16

Hheadend ........................................................................1help ...............................................................................7HFC Connector Module..............................10, 13, 14, 20HFC network .................................................................3hostname ......................................................................8

I initial maintenance......................................................19interface ........................................................................9interleave depth...........................................................13Interval Usage Code.....................................................15

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Juniper Networks G10 CMTS Operations and Maintenance46

Llong data grant interval ............................................... 19

MMAC domain ............................................................... 10major components ........................................................ 4maxburst size.............................................................. 16Media Gateways ............................................................ 3minislot size ................................................................15modulation............................................................ 13, 16modulation profile..................................... 15, 17, 18–19multicast packets......................................................... 20

Nnetwork side interface................................................... 3noise ........................................................................... 17

Ppasswords ..................................................................... 7ping............................................................................. 24power level.................................................................. 15preamble..................................................................... 16privilege .................................................................. 7, 22

QQPSK..................................................................... 17, 18

Rrange backoff .............................................................. 15request interval ........................................................... 19RF power..................................................................... 13running-config file ....................................................... 24

Sscrambler .................................................................... 16service flows ................................................................. 2ServiceGuard ............................................................... 25shared secret............................................................... 22short data grant interval .............................................. 19shortened last codeword ............................................. 16slots .............................................................................. 9spectrum analyzer................................................. 25, 26spectrum analyzer mode............................................. 27startup-config file ........................................................ 24station maintenance.................................................... 19system capacity............................................................. 2

Ttraceroute....................................................................24

Uupstream...............................................................14, 15upstream modulation profile .......................................15username ......................................................................8

Vvideo servers .................................................................3

Documents

Juniper Networks G10 CMTS · The G10 CMTS manages Internet data, voice and MPEG services. It func tions as the interface between the services networks—Internet, Publ ic Switched