Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
USA
http://www.cisco.com
Tel:
408 526-4000
800 553-NETS (6387)
Fax: 408 526-4100
Text Part Number: OL-0799-02
THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT
NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE
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PACKET THAT SHIPPED WITH THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO
LOCATE THE SOFTWARE LICENSE OR LIMITED WARRANTY, CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY.
The following information is for FCC compliance of Class A devices: This equipment has been tested and found to comply with the limits for a Class A
digital device, pursuant to part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference when the
equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio-frequency energy and, if not installed and used
in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential areais
likely to cause harmful interference, in which case users will be required to correct the interference at their own expense.
The following information is for FCC compliance of Class B devices: The equipment described in this manual generates and may radiate radio-frequency
energy. If it is not installed in accordance with Cisco’s installation instructions, it may cause interference with radio and television reception. This
equipment has been tested and found to comply with the limits for a Class B digital device in accordance with the specifications in part 15 of the FCC rules.
These specifications are designed to provide reasonable protection against such interference in a residential installation. However, there is no guarantee
that interference will not occur in a particular installation.
Modifying the equipment without Cisco’s written authorization may result in the equipment no longer complying with FCC requirements for Class A or
Class B digital devices. In that event, your right to use the equipment may be limited by FCC regulations, and you may be required to correct any
interference to radio or television communications at your own expense.
You can determine whether your equipment is causing interference by turning it off. If the interference stops, it was probably caused by the Cisco equipment
or one of its peripheral devices. If the equipment causes interference to radio or television reception, try to correct the interference by using one ormore
of the following measures:
• Turn the television or radio antenna until the interference stops.
• Move the equipment to one side or the other of the television or radio.
• Move the equipment farther away from the television or radio.
• Plug the equipment into an outlet that is on a different circuit from the television or radio. (That is, make certain the equipment and the television orradio
are on circuits controlled by different circuit breakers or fuses.)
Modifications to this product not authorized by Cisco Systems, Inc. could void the FCC approval and negate your authority to operate the product.
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All other brands, names, or trademarks mentioned in this document or Web site are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (0104R)
Placing the Cisco CVA122/CVA122E Cable Voice Adapter on a Desktop3-4
Side Mounting the Cisco CVA122/CVA122E Cable Voice Adapter3-5
Wall Mounting the Cisco CVA122/CVA122E Cable Voice Adapter3-7
Verifying Power Requirements3-9
Connecting Power3-10
Connecting to the Cable System3-11
Connecting to Telephones or Fax Devices3-12
Connecting to the Computer (Ethernet)3-14
Cisco CVA122/CVA122E Hardware Installation Guide
OL-0799-02 (05/2001)
Connecting to the Computer (USB)3-15
Power-On and Initialization Sequence3-16
Verifying Installation3-17
Internet Connection3-17
VoIP Telephone Connection3-18
Contents
CHAPTER
APPENDIX
4Troubleshooting4-1
Troubleshooting Overview4-1
Initialization and Self-Test Problems4-2
Troubleshooting Subsystems4-4
Coaxial Cable Subsystem4-7
RF and Digital Subsystem4-8
Ethernet Subsystem4-8
USB Subsystem4-9
PC Subsystem4-10
VoIP Subsystem4-12
Further Contacts4-13
ATechnical SpecificationsA-1
Physical, Power, and Environmental SpecificationsA-1
Data SpecificationsA-3
Voice SpecificationsA-5
APPENDIX
APPENDIX
OL-0799-02 (05/2001)
BConnector and Cable SpecificationsB-1
Coaxial Connector and Cable SpecificationsB-1
Ethernet Connector and CablingB-2
Power ConnectorB-4
USB Connector and CablingB-4
Voice Port ConnectorsB-5
CRegulatory Compliance and Safety InformationC-1
Safety InformationC-1
General SafetyC-1
Subscriber SafetyC-1
Regulatory StatementsC-2
FCC RequirementsC-2
Cisco CVA122/CVA122E Hardware Installation Guide
v
Contents
INDEX
Class B EquipmentC-2
Translated Safety WarningsC-2
Warning DefinitionC-2
Lightning Activity WarningC-3
Installation WarningC-4
Product Disposal WarningC-5
Jewelry Removal WarningC-6
Incorrect Connection WarningC-7
Ring Signal Generator WarningC-8
TN and IT Power WarningC-9
vi
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Preface
This document is the Cisco CVA122/CVA122E Cable Voice Adapter Hardware Installation Guide and
describes installing, powering on, and troubleshooting a Cisco CVA122/CVA122E Cable Voice Adapter.
The document also includes cabling and pinout information.
This section contains:
• Audience
• Purpose
• Organization
• Related Documentation
Audience
NoteThis document contains instructions to install or configure the Cisco CVA122/CVA122E Cable Voice
Purpose
• Obtaining Documentation
• Obtaining Technical Assistance
This guide is intended for coaxial networking transmission installers and technicians who are familiar
with the installation, maintenance, and troubleshooting of cable television wiring and equipment. Cable
system installers and technicians should be familiar with their cable plant’s base operating parameters
and subscriber service offerings. Cable system support engineers and administrators should be
acquainted with Ethernet, IEEE 802.3, and Universal Serial Bus (USB) type data communications
networks.
Adapter using procedures that only qualified personnel should perform. This document is not
intended for subscribers. See the “Related Documentation” section of this preface for the
documentation available for subscribers.
This guide covers the physical installation of the Cisco CVA122/CVA122E Cable Voice Adapter. These
procedures include site preparation, the physical placement of the cable voice adapter in an appropriate
location, the cabling required for the power, Ethernet, USB, voice, and cable connections, and
verification of the installation at the cable voice adapter’s initial power-on.
OL-0799-02 (04/2001)
Cisco CVA122/CVA122E Hardware Installation Guide
vii
Organization
These procedures do not require access to the cable voice adapter’s command-line interface (CLI).
However, CLI access might be required to configure the cable voice adapter and to bring it to full
operability. See the Cisco CVA122 Cable Voice Adapter Features and Cisco CVA122E Cable VoiceAdapter Features guides for instructions on configuring the cable voice adapter for network operation.
Organization
This guide is organized into the following chapters and appendixes:
Table 1Organization
ChapterTitleDescription
Chapter 1Product OverviewDescribes the Cisco CVA122/CVA122E Cable Voice
Chapter 2Preparing for InstallationOutlines site preparation requirements to meet before
Chapter 3Installing the
Chapter 4TroubleshootingContains basic installation troubleshooting information
Appendix A Technical SpecificationsContains the physical, environmental, power, data, and
Appendix B Connector and Cable
Appendix C Regulatory Compliance and
Cisco CVA122/CVA122E
Cable Voice Adapter
Specifications
Safety Information
Preface
Adapter, its operation, and its interaction with the Cable
Modem Termination System (CMTS).
installing a Cisco CVA122/CVA122E Cable Voice
Adapter at a subscriber site.
Provides instructions to connect the
Cisco CVA122/CVA122E Cable Voice Adapter, perform
its initial power-on, and verify its basic functionality.
appropriate to field service technicians. (This
information does not require access to the cable voice
adapter’s CLI interface.)
voice technical specifications for the cable voice adapter.
Contains the technical description of the interfaces on
the Cisco CVA122/CVA122E Cable Voice Adapter and
the most common cables that are used with them.
Contains international agency compliance, safety, and
statutory information for the Cisco CVA122/CVA122E
Cable Voice Adapter. This appendix also contains safety
warnings translated into multiple languages.
Conventions
NoteMeans reader take note. Notes contain helpful suggestions or references to materials not
TimesaverMeans the described action saves time. You can save time by performing the action
Cisco CVA122/CVA122E Hardware Installation Guide
viii
contained in this publication.
described in the paragraph.
OL-0799-02 (04/2001)
Preface
CautionMeans reader be careful. In this situation, you might do something that could result in
equipment damage or loss of data.
Safety Information Referral Warning
Organization
Warning
Waarschuwing
Varoitus
Attention
Warnung
Avvertenza
Before you install, operate, or service the system, read the Site Preparation and Safety Guide. This guide contains important safety information you should know before
working with the system.
Lees de handleiding Voorbereiding en veiligheid van de locatie Handleiding voordat u
het systeem installeert of gebruikt of voordat u onderhoud aan het systeem uitvoert.
Deze handleiding bevat belangrijke beveiligingsvoorschriften waarvan u op de hoogte
moet zijn voordat u met het systeem gaat werken.
Ennen kuin asennat järjestelmän tai käytät tai huollat sitä, lue Asennuspaikan valmistelu-jaturvaopas -opasta. Tässä oppaassa on tärkeitä turvallisuustietoja, jotka
tulisi tietää ennen järjestelmän käyttämistä.
Avant d'installer le système, de l'utiliser ou d'assurer son entretien, veuillez lire le
Guide de sécurité et de préparation du site. Celui-ci présente des informations
importantes relatives à la sécurité, dont vous devriez prendre connaissance.
Warnhinweis Bevor Sie das System installieren, in Betrieb setzen oder warten, lesen
Sie die Anleitung zur Standortvorbereitung und Sicherheitshinweise. Dieses
Handbuch enthält wichtige Informationen zur Sicherheit, mit denen Sie sich vor dem
Verwenden des Systems vertraut machen sollten.
Prima di installare, mettere in funzione o effettuare interventi di manutenzione sul
sistema, leggere le informazioni contenute nella documentazione sulla Guida alla sicurezza. Tale guida contiene importanti informazioni che è necessario acquisire
prima di iniziare qualsiasi intervento sul sistema.
Advarsel
Aviso
OL-0799-02 (04/2001)
Før du installerer, tar i bruk eller utfører vedlikehold på systemet, må du lese
Veiledning for stedsklargjøring og sikkerhet. Denne håndboken inneholder viktig
informasjon om sikkerhet som du bør være kjent med før du begynner å arbeide med
systemet.
Antes de instalar, funcionar com, ou prestar assistência ao sistema, leia o Guia de Preparação e Segurança do Local. Este guia contém informações de segurança
importantes que deve conhecer antes de trabalhar com o sistema.
Cisco CVA122/CVA122E Hardware Installation Guide
ix
Related Documentation
Preface
¡Advertencia!
Varning!
Antes de instalar, manejar o arreglar el sistema, le aconsejamos que consulte la Guía de prevención y preparación de una instalación. Esta guía contiene importante
información para su seguridad que debe saber antes de comenzar a trabajar con el
sistema.
Innan du installerar, använder eller utför service på systemet ska du läsa
Förberedelser och säkerhet Handbok. Denna handbok innehåller viktig
säkerhetsinformation som du bör känna till innan du arbetar med systemet.
Related Documentation
Refer to the following Cisco documents for related information. The documents can be found online at
Cisco.com or on the Documentation CD-ROM. You can also order printed copies of most current
documents.
NoteThe list that follows is not all-inclusive. New documents and revisions occur frequently.
• CiscoWorks documentation for networks that use the Simple Network Management Protocol
(SNMP) to monitor Cisco CVA122/CVA122E Cable Voice Adapters
• MIB information is available on CCO at ftp://ftp.cisco.com/pub/mibs.
Obtaining Documentation
The following sections provide sources for obtaining documentation from Cisco Systems.
World Wide Web
You can access the most current Cisco documentation on the World Wide Web at the following sites:
• http://www.cisco.com
• http://www-china.cisco.com
• http://www-europe.cisco.com
OL-0799-02 (04/2001)
Cisco CVA122/CVA122E Hardware Installation Guide
xi
Obtaining Technical Assistance
Documentation CD-ROM
Cisco documentation and additional literature are available in a CD-ROM package, which ships
with your product. The Documentation CD-ROM is updated monthly and may be more current than
printed documentation. The CD-ROM package is available as a single unit or as an annual subscription.
Ordering Documentation
Cisco documentation is available in the following ways:
• Registered Cisco Direct Customers can order Cisco Product documentation from the Networking
Products MarketPlace:
http://www.cisco.com/cgi-bin/order/order_root.pl
• Registered Cisco.com users can order the Documentation CD-ROM through the online Subscription
Store:
http://www.cisco.com/go/subscription
• Nonregistered Cisco.com users can order documentation through a local account representative by
calling Cisco corporate headquarters (California, USA) at 408 526-7208 or, in North America, by
calling 800 553-NETS(6387).
Preface
Documentation Feedback
If you are reading Cisco product documentation on the World Wide Web, you can submit technical
comments electronically. Click Feedback in the toolbar and select Documentation. After you complete
the form, click Submit to send it to Cisco.
You can e-mail your comments to bug-doc@cisco.com.
To submit your comments by mail, use the response card behind the front cover of your document, or
write to the following address:
Attn Document Resource Connection
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-9883
We appreciate your comments.
Obtaining Technical Assistance
Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can
obtain documentation, troubleshooting tips, and sample configurations from online tools. For Cisco.com
registered users, additional troubleshooting tools are available from the TAC website.
xii
Cisco CVA122/CVA122E Hardware Installation Guide
OL-0799-02 (04/2001)
Preface
Cisco.com
Obtaining Technical Assistance
Cisco.com is the foundation of a suite of interactive, networked services that provides immediate, open
access to Cisco information and resources at anytime, from anywhere in the world. This highly
integrated Internet application is a powerful, easy-to-use tool for doing business with Cisco.
Cisco.com provides a broad range of features and services to help customers and partners streamline
business processes and improve productivity. Through Cisco.com, you can find information about Cisco
and our networking solutions, services, and programs. In addition, you can resolve technical issues with
online technical support, download and test software packages, and order Cisco learning materials and
merchandise. Valuable online skill assessment, training, and certification programs are also available.
Customers and partners can self-register on Cisco.com to obtain additional personalized information and
services. Registered users can order products, check on the status of an order, access technical support,
and view benefits specific to their relationships with Cisco.
To access Cisco.com, go to the following website:
http://www.cisco.com
Technical Assistance Center
The Cisco TAC website is available to all customers who need technical assistance with a Cisco product
or technology that is under warranty or covered by a maintenance contract.
Contacting TAC by Using the Cisco TAC Website
If you have a priority level 3 (P3) or priority level 4 (P4) problem, contact TAC by going to the TAC
website:
http://www.cisco.com/tac
P3 and P4 level problems are defined as follows:
• P3—Your network performance is degraded. Network functionality is noticeably impaired, but most
business operations continue.
• P4—You need information or assistance on Cisco product capabilities, product installation, or basic
product configuration.
In each of the above cases, use the Cisco TAC website to quickly find answers to your questions.
To register for Cisco.com, go to the following website:
http://www.cisco.com/register/
If you cannot resolve your technical issue by using the TAC online resources, Cisco.com registered users
can open a case online by using the TAC Case Open tool at the following website:
http://www.cisco.com/tac/caseopen
Contacting TAC by Telephone
If you have a priority level 1(P1) or priority level 2 (P2) problem, contact TAC by telephone and
immediately open a case. To obtain a directory of toll-free numbers for your country, go to the following
website:
• P1—Your production network is down, causing a critical impact to business operations if service is
not restored quickly. No workaround is available.
• P2—Your production network is severely degraded, affecting significant aspects of your business
operations. No workaround is available.
Preface
xiv
Cisco CVA122/CVA122E Hardware Installation Guide
OL-0799-02 (04/2001)
CHAPTER
Product Overview
This chapter describes the Cisco CVA122/CVA122E Cable Voice Adapter and its interaction with the
Cable Modem Termination System (CMTS)—the cable system headend equipment that provides
Internet (TCP/IP) connectivity for subscribers over the cable broadband infrastructure. The chapter
provides physical and functional overviews of the Cisco CVA122/CVA122E Cable Voice Adapter.
This section provides an overview of the Cisco CVA122/CVA122E Cable Voice Adapter, its hardware,
and its basic operation:
• Introduction
• Initial Power-On and Provisioning
• Data Operations
• Vo i c e O p e ra t i o n s
1
Introduction
NoteUnless otherwise indicated, all information in this manual applies to both the
OL-0799-02 (05/2001)
The Cisco CVA122 Cable Voice Adapter and Cisco CVA122E Cable Voice Adapter function at the most
basic level as a cable modem—a modulator/demodulator that provides high-speed network access on
the cable television system to residential subscribers. The two models are based on
• The Cisco CVA122 Cable Voice Adapter is based on the Data-Over-Cable Service Interface
Specifications (DOCSIS), a standard developed with service providers to ensure that any
DOCSIS-certified cable modem can interoperate with any bidirectional, DOCSIS-qualified CMTS.
The DOCSIS standard supports the North American National Television Systems Committee
(NTSC) channel plan, with 6 MHz channel widths, a downstream range of 88 to 860MHz, and an
upstream range of 5 to 42 MHz.
• The Cisco CVA122E Cable Voice Adapter is based on the European Data-Over-Cable Service
Interface Specifications (EuroDOCSIS), which is almost identical to the DOCSIS standard, except
that it supports the European Phase Alternating Line (PAL) and Systeme Electronique Couleur
Avec Memoire (SECAM) channel plans, with 8 MHz channel widths, a downstream range of 88 to
860MHz,andanupstreamrangeof5to65MHz.
Cisco CVA122 and Cisco CVA122E Cable Voice Adapters.
Tip sInformation about DOCSIS and EuroDOCSIS requirements and current specifications are
available at the CableLabs web site at http://www.cablelabs.com.
The Cisco CVA122/CVA122E Cable Voice Adapter uses its cable interface to connect to the CMTS over
the Hybrid/Fiber Coax (HFC) cable system. A personal computer (PC) connects to the
Cisco CVA122/CVA122E Cable Voice Adapter through either the Ethernet or USB interface.
The cable voice adapter then acts as an IP bridge, providing Internet access by forwarding traffic
between the PC and the CMTS. Subscribers can use the Cisco CVA122/CVA122E Cable Voice Adapter
to create high-speed, permanent access to the Internet, without the need for telco-based services such
as leased lines.
If supported by the service provider, the Cisco CVA122/CVA122E Cable Voice Adapter can connect to
two PCs by attaching a PC to each interface (Ethernet and USB). In addition, the cable voice adapter’s
Ethernet interface can connect to an Ethernet hub, and additional computers can then be connected to
the hub.
NoteTo be complaint with the USB specification, the Cisco CVA122/CVA122E Cable Voice
Adapter does not support networking multiple PCs using a USB bridging hub.
Chapter 1Product Overview
In addition to providing DOCSIS connectivity, the Cisco CVA122/CVA122E Cable Voice Adapter can
optionally provide Voice over IP (VoIP) services, allowing subscribers to make telephone, modem, and
FAX calls over TCP/IP networks such as the Internet. These calls can be made to other VoIP devices,
or to telephone, modem, or FAX devices on the regular telephone network (the Public Telephone
Switched Network, commonly known as PTSN).
The Cisco CVA122/CVA122E Cable Voice Adapter can optionally be configured as an IP router, using
static routes and the RIPv2 routing protocol. When operating in routing mode, the cable voice adapter
can treat its cable, Ethernet, and USB interfaces as separately routable interfaces.
Bridging and routing operations are summarized in the following sections.
Bridging Operations
When acting as a DOCSIS-compliant cable modem, the Cisco CVA122/CVA122E Cable Voice Adapter
provides IP bridging for one or more PCs and other customer premises equipment (CPE). In this mode,
traffic from the cable voice adapter’s Ethernet and USB interfaces is transparently forwarded on to the
cable interface for transmission to the CMTS. Similarly, the cable voice adapter receives traffic on the
cable interface and forwards it to the PCs attached to the Ethernet and USB interfaces.
In bridging mode, the PCs must be assigned IP addresses in the same subnet as the CMTS. Typically, a
Dynamic Host Configuration Protocol (DHCP) server at the headend automatically assigns the IP
addresses to each PC that is authorized to connect to the Cisco CVA122/CVA122E Cable Voice
Adapter.
You can connect a PC directly to the Ethernet port, the USB port, or both ports; if supported by the
service provider, you can also connect an Ethernet hub directly to the Ethernet port and then connect
multiple PCs to the hub. In bridging mode, the Cisco CVA122/CVA122E Cable Voice Adapter supports
a maximum 254 PCs, depending on the maximum number allowed by the CMTS.
1-2
By default, one PC is supported for each cable voice adapter. The service provider can change this limit
by changing the MAX CPE parameter in the DOCSIS configuration file. However, the CMTS at the
headend can also enforce its own limit on CPE devices, and the CMTS limit overrides the MAX CPE
Cisco CVA122/CVA122E Hardware Installation Guide
OL-0799-02 (05/2001)
Chapter 1Product Overview
parameter. So if the headend allowed only one PC per cable voice adapter, subscribers could connect
only one PC to the cable voice adapter, even if the MAX CPE parameter were set to the maximum
possible value of 254.
NoteFor better network performance, Cisco recommends a maximum limit of 16 CPE devices;
this recommended maximum might be less depending on the services the subscriber has
purchased.
See Figure 1-1 for a typical configuration.
Figure 1-1Cisco CVA122/CVA122E in a Bridging Configuration
NoteAll Cisco IOS releases that support the Cisco CVA122/CVA122E Cable Voice Adapter
support basic DOCSIS connectivity that provides both high-speed Internet data access and
VoIP connectivity.
The cable voice adapter ships from the factory with a Cisco IOS software image stored in nonvolatile
Flash memory that supports DOCSIS-compliant bridging data operations. Based on the feature licenses
your company purchased, other Cisco IOS images can be downloaded from Cisco Connection Online
(CCO). These images might provide additional functionality, depending on the software release.
Routing Operations
When configured as a router, the Cisco CVA122/CVA122E Cable Voice Adapter can directly connect
one PC to each of its Ethernet and USB ports at the rear of the router. The Ethernet port can also be
connected to a standard 10BaseT Ethernet hub, which then connects additional computers or Ethernet
devices at the site to a local area network (LAN).
In routing mode, the Cisco CVA122/CVA122E Cable Voice Adapter is typically configured to use the
IP address of the headend router as its default IP gateway. Routing mode does not have a maximum
limitation on the number of CPE devices, as is the case in bridging mode; however, the CMTS can still
limit the number of CPE devices by limiting the number of IP addresses that any particular cable modem
can provide services for. If this is the case, the cable voice adapter can use NAT/PAT translations to use
one IP address for multiple CPE devices.
HFC
network
CATV
coaxial cable
Cisco CVA120 Series
cable voice adapter
USB
PC
PC
Ethernet
35823
Upgrading the Software Image
When Cisco IOS images are updated to new releases, the service provider can download them as needed
to Cisco CVA122/CVA122E Cable Voice Adapters installed in the field (based on the software licenses
purchased). See the release notes for the cable voice adapter for a complete list of features and
Cisco IOS images that are currently supported.
Service providers can use the cable voice adapter’s Media Access Controller (MAC) address to uniquely
identify each particular unit in the field. The CMTS uses this value to download the proper DOCSIS
configuration file to the cable voice adapter before it begins operation.
The DOCSIS configuration file can also contain the name of the software image that the cable voice
adapter should be running. If necessary, the CMTS can download the proper software image to the cable
voice adapter and force it to reboot using the new image.
The download of the DOCSIS configuration file usually takes only a few seconds and is done every time
the Cisco CVA122/CVA122E Cable Voice Adapter reboots. The download of the software image can
take several minutes to complete, during which time network connectivity is not available. However,
the software image must be downloaded only once, until the subscriber needs to be updated with a new
image.
The section “Initial Power-On and Provisioning” explains this process. See the Cisco CVA122 CableVoice Adapter Features guide for a description on how to download a software image and configuration
file to a Cisco CVA122/CVA122E Cable Voice Adapter installed in the field.
Upgrading the ROM Monitor Software
The Cisco CVA122/CVA122E Cable Voice Adapter supports both a primary and secondary ROM
Monitor (ROMMON). The primary ROMMON is permanently installed, while the secondary
ROMMON is upgradable.
After power-on or a hard system reset, the primary ROMMON initially takes control. It then checks for
the presence of a secondary ROMMON and if present, verifies that the secondary ROMMON has the
correct checksum. If the secondary ROMMON passes these validation tests, the primary ROMMON
passes control to the secondary ROMMON, which first performs a power-on self-test and hardware
initialization, and then loads and executes the Cisco IOS software image. Otherwise, the primary
ROMMON remains in control and continues the boot process.
Chapter 1Product Overview
This approach allows the secondary ROMMON to be safely upgraded when new software is available.
If the file transfer is interrupted, or if the new ROMMON software becomes corrupted, the primary
ROMMON is still available to boot the Cisco CVA122/CVA122E Cable Voice Adapter and load the
Cisco IOS software image. The upgrade of the secondary ROMMON can then be attempted again.
Initial Power-On and Provisioning
The cable voice adapter ships from the Cisco factory ready to work in a DOCSIS-compliant bridging
data-only mode. However, before the cable voice adapter can transmit traffic, the CMTS at the headend
must properly provision the unit as follows:
• The appropriate service must be purchased from the cable system. If certain features, such as VoIP
support, are desired, a license for the appropriate Cisco IOS software image must also be
purchased.
• When the cable voice adapter is first brought online, the CMTS at the headend downloads a
DOCSIS configuration file to the cable voice adapter. This file—which is a binary file that must be
in the format required by the DOCSIS specification—configures the cable voice adapter for the
appropriate level of services and sets other parameters as needed.
• At this point the cable voice adapter is completely configured for basic DOCSIS operations, but if
necessary, the DOCSIS configuration file can also specify that the cable voice adapter should
download another Cisco IOS image from the CMTS.
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Chapter 1Product Overview
• To customize the cable voice adapter’s configuration further, the DOCSIS configuration file can
NoteThe Cisco CVA122/CVA122E Cable Voice Adapter downloads the DOCSIS configuration
file each time it is powered on, but it downloads the Cisco IOS image and Cisco IOS
configuration file only when needed. A new configuration file or image can be
downloaded whenever necessary, such as when the cable service offers new services or
subscribers upgrade their services.
To ensure that subscribers obtain the exact services they have ordered, the Cisco CVA122/CVA122E
Cable Voice Adapter arrives from the Cisco factory with a unique identifier (UID) that consists of a
serial number and MAC address. These factory-assigned values are on a label at the bottom of the cable
voice adapter; for convenience, these values are also in a barcode label that can be easily scanned for
easy entry into the service provider’s provisioning and billing system.
Using the MAC address of the cable voice adapter as the key, the CMTS downloads the DOCSIS
configuration file and Cisco IOS image that will provide the services that this particular subscriber has
purchased. Service technicians at the headend typically create a number of standard configuration files
to match the range of services offered by the provider; these configuration files can be created manually
or with tools provided by Cisco Systems for this purpose.
The following sections describe the initial power-on and provisioning sequence in more detail, as well
as the requirements that must be met by both the cable voice adapter and the CMTS before provisioning
can succeed.
also specify a Cisco IOS configuration file that the CMTS should download to the cable voice
adapter. This second configuration file is an ASCII text file that contains the Cisco IOS commands
needed to configure the cable voice adapter for advanced features, such as VoIP.
Initial Power-On Sequence
When connected and first powered on, the Cisco CVA122/CVA122E Cable Voice Adapter performs the
following DOCSIS-mandated procedure for automatic installation and configuration:
1. The cable voice adapter boots the Read Only Memory (ROM) from the ROMMON partition of its
Flash memory.
2. The cable voice adapter performs a self-test, initializes processor hardware, and boots the main
operating system software—the Cisco IOS release image stored in Flash memory.
3. The cable voice adapter acquires a temporary downstream channel by matching the clock sync
signal that is regularly sent out by the CMTS in the downstream frequency range.
4. The cable voice adapter then waits for an Upstream Channel Descriptor (UCD) message from the
CMTS and configures itself for the upstream frequency specified in that message.
5. The cable voice adapter waits for the next upstream bandwidth allocation map message (MAP).
These messages are regularly sent from the CMTS to find the next available shared request timeslot.
The cable voice adapter then uses this timeslot to send a ranging request message to the CMTS,
communicating the cable voice adapter’s user ID (UID, which includes its unique MAC address),
using a temporary service identifier (SID) of 0 (zero) to indicate it has not yet been allocated an
upstream channel.
6. In reply to the cable voice adapter’s ranging request, the CMTS sends a ranging response containing
a temporary SID to be used for the initial cable voice adapter configuration and bandwidth
allocation. As needed, the cable voice adapter adjusts its transmit power levels using the power
increment value given by the CMTS in its ranging response message.
NoteAt this point, the cable voice adapter has established connectivity with the CMTS
but is not yet online. The next steps allocate permanent upstream and downstream
frequencies, as well the configuration required for IP network connectivity.
7. After the next MAP message broadcast, the cable voice adapter uses a shared request timeslot to
invoke the Dynamic Host Configuration Protocol (DHCP) to establish IP connectivity with the
TCP/IP network at the headend.
8. The DHCP server—typically a dedicated server at the headend, but it could also be a CMTS such
as a Cisco uBR7200 series universal broadband cable voice adapter—sends a response containing
the cable voice adapter’s IP address, as well as the IP addresses for the default gateway and time of
day (ToD) server. It also sends the IP address for the authorized Trivial File Transfer Protocol
(TFTP) server from which the cable voice adapter should download its DOCSIS configuration file.
Depending on the particular network configuration, other information could be provided, such as
the IP addresses for a syslog server or security server.
9. The cable voice adapter configures itself for the specified IP address and gets the current date and
time from the specified ToD server.
10. Using the TFTP protocol, the cable voice adapter downloads the specified DOCSIS configuration
file and configures itself for the appropriate parameters. The DOCSIS configuration file defines the
cable voice adapter’s operating mode such as the provisioned downstream and upstream service
assignments, assigned frequencies, data rates, modulation schemes, Class of Service (CoS), type of
services to support, and other parameters. Cisco provides tools to help automate the creation of
configuration files.
Chapter 1Product Overview
CautionThe DOCSIS configuration file must be in the exact format given by the DOCSIS
specification. An incorrect DOCSIS configuration file can cause the
Cisco CVA122/CVA122E Cable Voice Adapter to constantly cycle offline. Such errors
include: wrong downstream frequency; wrong UCD; wrong downstream Channel ID;
invalid CoS; incorrect BPI privacy configurations or shared secret strings.
11. The cable voice adapter sends another registration request to the CMTS containing the CoS
parameters given in the DOCSIS configuration file.
12. The CMTS verifies that the cable voice adapter is using the appropriate CoS profile and converts
the temporary SID into a data SID with a service class index that points to the applicable CoS
profile.
NoteDepending on the software image being run and the capabilities of the CMTS, the
DOCSIS configuration file can also specify multiple CoS profiles. Each CoS
profile is assigned its own SID, either dynamically or statically, depending on the
capabilities of the CMTS and software image being used.
13. The cable voice adapter completes its secondary ranging and is then online, passing data between
the cable network and the PCs and other CPE devices connected to the cable voice adapter.
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Chapter 1Product Overview
NoteAt this point the cable voice adapter is online and operational in the basic DOCSIS
14. If the DOCSIS configuration file specifies that the cable voice adapter must download another
15. If Baseline Privacy Interface (BPI) encryption is configured and enabled on both the cable voice
Figure 1-2 illustrates the traffic flow during this process.
bridging mode (“plug and play” mode). The next step is done only if the DOCSIS
configuration file specifies that the cable voice adapter must also download a
Cisco IOS configuration file and new Cisco IOS image.
Cisco IOS image and a Cisco IOS configuration file, the cable voice adapter uses TFTP to
download the image and configuration files into its local memory. It then installs the new Cisco IOS
image and runs the configuration file.
adapter and CMTS, the cable voice adapter and CMTS negotiate the appropriate
encryption/decryption parameters. After encryption is enabled, all information sent over the cable
interface is encrypted to prevent interception or modification by an unauthorized party.
CMTS Interface
MAP Broadcast
Contains timesharing info
Send UCD
DHCP Response:
Contains IP addresses
Default gateway, TOD server
TFTP server address
TFTP boot config file name
Fail if QoS not available
or authentication failed
Cisco CVA120 Series cable voice adapter
Power on
Establish synch and wait for UCD
Obtain upstream parameters
Use temporary SID
Extract slot info and upstream
channel to use
Start ranging
Transmit ranging packet with SID
DHCP request/TFTP boot request
Now in allocated slots
ToD Request
Registration Request
Send QoS Parameters
Now in allocated slots
Cisco CVA120 Series online
35821
NoteFor more detail on the provisioning process, see the DOCSIS Radio Frequency Interface
(RFI) specification (SP-RFII01-990731 or later revision).
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After the Cisco CVA122/CVA122E Cable Voice Adapter goes online, it sends traffic between the
attached PCs and other CPE devices and the network (Internet, Intranet, VoIP). Because the cable voice
adapter is operating in DOCSIS bridging mode, the service provider typically provides the IP addresses
to the PCs and other CPE devices. The number of IP addresses each subscriber can obtain depends on
the services purchased from the provider.
The following requirements must be met before a cable voice adapter can be provisioned:
• All required CMTS routing and network interface equipment must be installed, configured, and
operational. This includes all headend routers, servers (DHCP, TFTP, and TOD), network
management systems, and/or other configuration or billing systems required for your network.
• Based on the quality and capacity of your cable plant, your system administrator or network planner
must have defined your network’s IP address allocation plan; spectrum management plan outlining
the recommended operating parameters to optimize performance; channel plan identifying the
channels available to assign to specific Cisco CVA122/CVA122E Cable Voice Adapters; and dial
plan to match the supported VoIP protocol.
• A CMTS customer service representative must have recorded all needed subscriber information,
initiated a work order, and arranged an installation date with the subscriber. For subscriber sites that
support multiple telephones or fax devices on a telephone line, all wiring associated with the
telephone line extension must be in place. Inside wiring must be in compliance with the country of
operation to prevent degradation of service.
• The CMTS system administrator or appropriate personnel must have specified the policy
parameters for the Cisco CVA122/CVA122E Cable Voice Adapter and all computers and other CPE
devices to be supported at the subscriber site. See Cisco’s Network Registrar (CNR) product
documentation for more information.
Chapter 1Product Overview
• The CMTS system administrator or appropriate personnel must have defined and pushed DHCP and
DOCSIS configuration files to the appropriate servers so that each cable voice adapter, when
initialized, can transmit a DHCP request, receive its IP address, obtain its TFTP and TOD server
addresses, and download its DOCSIS configuration file. Cisco IOS images and Cisco IOS
configuration files must also be prepared for subscribers who are purchasing services that require
new software images and advanced configurations.
NoteThe CMTS uses the cable voice adapter’s unique MAC address for the cable
interface to ensure that the cable voice adapter downloads only the file(s)
appropriate for the levels of service that have been purchased.
• If DHCP is also being used to provision the IP addresses used by the CPE devices at the subscriber’s
site, the DHCP server must be able to respond to those requests as well.
• The CMTS system administrator must ensure appropriate databases are updated to activate and
support the new subscriber account in the provisioning, billing, and/or network management
systems in place for your network after each cable voice adapter is registered with the CMTS.
• The following files should be prepared and available on the TFTP server:
–
DOCSIS configuration file—This is required for every installation. The DOCSIS configuration
file specifies the DOCSIS-mandated parameters, such as upstream and downstream
frequencies, as well as optional features, such as whether to download a new software image
or a Cisco IOS configuration file.
–
Cisco IOS image—If upgrading to a Cisco IOS image different from the factory default, that
image must be specified in the DOCSIS configuration file and available on a TFTP server that
is accessible through the cable interface.
1-8
–
Cisco IOS configuration file—This text file contains the Cisco IOS command-line interface
(CLI) commands that configure the cable voice adapter for any special configurations and
optional features. It must be made available on a TFTP server that is accessible through the
cable interface.
Cisco CVA122/CVA122E Hardware Installation Guide
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Chapter 1Product Overview
Data Operations
This section provides an overview of how data is transmitted to and from the Cisco CVA122/CVA122E
Cable Voice Adapter across the cable system’s HFC network. Figure 1-3 illustrates a typical broadband
data cable system, showing the network path between the Cisco CVA122/CVA122E Cable Voice
Adapter and the CMTS headend equipment (Cisco uBR7200 series universal broadband router or other
DOCSIS-compliant CMTS).
Upstream and downstream data interfaces
Operation support system interface
Downstream RF interface
Upstream RF interface
Combiner
Tx
Fiber
Rx
Cisco CVA120 Series
cable voice adapter
HFC
cable
plant
Residence
subscriber site:
cable RF interface
Ethernet interface
USB interface
35822
The Cisco CVA122/CVA122E Cable Voice Adapter provides the connection between the PC and the
cable system, modulating the data transmitted to and from the PC so that it can be carried over the
coaxial cable installed by the service provider. To avoid interfering with the cable video signals that are
also transmitted over this same coaxial cable, the DOCSIS specification allows only certain frequencies
to be used for data transmissions. Separate frequencies are used for the data sent from the CMTS to the
cable modem (the downstream direction) and for the data sent from the cable modem to the CMTS (the
upstream direction).
The CMTS divides the cable plant into downstream channels and upstream segments or clusters of
nodes. Each Cisco CVA122/CVA122E Cable Voice Adapter on the network is configured to receive data
on a particular downstream channel. A downstream channel contains one or more upstream segments;
partitioning the upstream plant into smaller segments significantly reduces the number of potential
ingress sources and failure points.
Downstream Transmissions
Because 90% of the data transmitted on the Internet is, on average, sent from the network to the user,
the cable system allocates the majority of bandwidth for downstream data (data sent from the CMTS to
thecablevoiceadapter).Downstreamtransmissionsusea6MHzdatachannelinthe88to860MHz
range, providing an approximate maximum bandwidth of 27 or 26 Mbps. This bandwidth is shared
among all subscribers who have been assigned to this particular downstream channel.
The CMTS receives the downstream data from its Internet or other WAN connections. It addresses the
data to the appropriate Cisco CVA122/CVA122E Cable Voice Adapter and modulates it for
transmission on the cable network. When the data arrives at the subscriber’s site, the cable voice adapter
modulates it for transmission over the Ethernet or USB connection to the appropriate CPE device.
Upstream Transmissions
The data transmitted in the upstream direction (from the user to the network) is typically much less than
that on the downstream direction, so a smaller bandwidth is allocated to it. The upstream transmissions
share a 200 kHz-wide to 3.2 MHz-wide channel in the 5 to 42 MHz range, providing a bandwidth of up
to 10 Mbps.
Depending on the quality of the physical plant and the CMTS used at the headend, users on a single
downstream can be allocated across several upstreams to ensure a responsive network. Service
providers can allocate different upstream bandwidths depending on the services purchased by a
subscriber. For example, a subscriber purchasing basic home service might be allocated a 128 kbps
upstream, while businesses purchasing premium services might be allocated a 384 kbps upstream.
The Cisco CVA122/CVA122E Cable Voice Adapter receives the upstream data from the CPE devices
to which it is connected. It modulates this data for transmission on the coaxial cable system to the
CMTS. The CMTS then routes the data to the appropriate destination (local server, Internet, and so
forth) through its WAN interfaces.
Chapter 1Product Overview
All DOCSIS cable modems use a request/grant mechanism to obtain bandwidth on the upstream. The
CMTS grants the bandwidth according to the requestor’s level of service, ensuring that the cable modem
is not exceeding the maximum bandwidth for upstream transmissions that has been specified by the
subscriber’s service agreement.
NoteEnd-to-end throughput varies based on the design and loading of network components, the
mix of traffic, the processing speed and interface of the host server(s), the processing
speed and network performance of the subscriber’s computer, as well as other parameters.
Because the network can be configured to support multiple levels of service with different
performance requirements, the subscriber’s service level agreement also affects
throughput. DOCSIS also specifies fundamental performance limitations to ensure that the
majority of subscribers experience good performance, rather than permitting a few users
to consume the entire capacity.
Voice Operations
The Cisco CVA122/CVA122E Cable Voice Adapter supports Voice over IP (VoIP), which transmits
voice, modem, and FAX calls over a TCP/IP network such as the Internet. Depending on the services
purchased from the cable service provider, subscribers can place and receive calls without using the
local exchange carrier.
The cable voice adapter contains two voice ports, which support two simultaneous voice, modem, and
FAX calls. You can connect a single-line telephone or FAX device to each voice port, or you can connect
a dual-line telephone or FAX device to the first voice port.
1-10
Subscribers can connect standard analog telephones, modems, and FAX machines to the
Cisco CVA122/CVA122E Cable Voice Adapter; IP telephones are not required. Depending on the voice
network set up by the service provider, subscribers can place calls to numbers that are in the existing
telco network; the called party does not have to be using VoIP telephone service.
Station) services and supports analog phones, faxes, and modems. The
Cisco CVA122/CVA122E Cable Voice Adapter’s voice ports do not support devices
requiring Foreign Exchange Office (FXO) services, such as PBX devices.
You can also connect multiple telephones, modems, and FAX devices to a single voice line. However,
each multiple device acts as an extension to that voice line, so only one call at a time can be made per
voice line. The Cisco CVA122/CVA122E Cable Voice Adapter supports multiple devices per voice line,
however, the total REN value for all devices must not exceed the maximum number given in
Appendix A, “Technical Specifications.”
NoteThe REN value is a measure of the AC load that the device places on a voice line and is
typically listed on each device. If too many devices are connected to the line, the
telephones might not ring properly, and you might have difficultly completing telephone
calls.
Telephones at each subscriber site must support touch-tone dialing; rotary dialing is not supported.
Special telephone features such as call waiting, forwarding, and conferencing are supported only if
using a Cisco IOS image that supports those particular features.
Features
NoteFAX devices—standard Group III and computer-based Group III machines up to 14,400
CautionIn certain countries, the provisioning of voice telephony over the Internet or use of these
Features
baud—are supported.
products may be prohibited and/or subject to laws, regulations or licenses, including
requirements applicable to the use of the products under telecommunications and other
laws and regulations; customer must comply with all such applicable laws in the country
where the customer intends to use the product.
The Cisco CVA122/CVA122E Cable Voice Adapter is a compact, easy-to-install device that contains:
• One F-connector interface to the cable system.
• One RJ-45 (10BaseT half-duplex Ethernet) interface to connect a PC directly to the cable voice
adapter. If supported by the service provider, this port can connect an Ethernet hub, which then
connects to multiple PCs.
• One USB device (type “B” connector) port to connect a PC directly to the cable voice adapter.
NoteThe Cisco CVA122/CVA122E Cable Voice Adapter does not support networking
multiple PCs using a USB bridging hub.
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• Two RJ-11 Foreign Exchange Station (FXS) ports to connect analog telephones, modems, and fax
devices to the cable system and IP backbone.
Cisco CVA122/CVA122E Hardware Installation Guide
1-11
Features
Chapter 1Product Overview
Figure 1-4 depicts the front of the Cisco CVA122/CVA122E Cable Voice Adapter. Figure 1-5 shows the
rear of the unit.
Figure 1-4Cisco CVA122/CVA122E Cable Voice Adapter Front View
The following sections describe the cable voice adapter and its features in more detail:
• LED Descriptions
• Data Ports
• Voice Ports
• Power Supply
See Appendix B, “Connector and Cable Specifications,” for the pinouts and cabling information for
each of these connectors.
LED Descriptions
The front panel on the Cisco CVA122/CVA122E Cable Voice Adapter contains 4 LEDs to provide
information about the cable voice adapter’s status and network connections. Figure 1-6 illustrates each
LED and Table 1-1 lists its meaning.
Ethernet
X
Ethernet
USB port
Phone
USB
V1+V2
Phone (RJ-11)
V2
Power receptacle
Power
+5,-30,-56
Cable TV In
V
Cable F-connector
35995
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Chapter 1Product Overview
Figure 1-6Cisco CVA122/CVA122E Cable Voice Adapter Front Panel LEDs
Features
Cable StatusEthernet StatusUSB StatusMessage
Table 1-1Cisco CVA122/CVA122E Cable Voice Adapter Front Panel LED Description
LabelDescriptionColorFunction
Cable StatusGreenOn = RF link is up, and the Cisco CVA122 power-on and self-test diagnostics have
completed successfully, the system image has been booted, and the system is
operational.
Blink = Cisco CVA122 is searching for a downstream frequency or has lost
downstream lock.
Off = No Power; RF link down.
Ethernet
Status
USB StatusGreenOn = Link Up.
MessageGreenReserved for service provider use (for example, it could indicate that messages are
GreenOn = Link Up.
Blink = Activity on the Ethernet interface.
Off = Link Down or Ethernet cable disconnected.
Blink = Activity on the USB interface.
Off = Link Down or USB cable disconnected.
waiting in the subscriber’s voicemail or email, but the exact usage depends on the
service provider).
35779
NoteIf the cable voice adapter fails one of its self-tests, the LEDs also contain information
Data Ports
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Blink = After power-on and self-test diagnostics have completed successfully,
LED blinks as the system image is booted.
about the type of failure. See Table 4-1 on page 4-3 for more details.
As shown in Figure 1-5, the Cisco CVA122/CVA122E Cable Voice Adapter contains a coaxial cable
F-connector, one Ethernet 10Base T (RJ-45) connector, and one USB device (device, type “B”)
connector. The cable F-connector must always be connected to the cable system for proper operation.
The Ethernet and USB connectors can be connected in one of the following configurations:
• A PC can be connected to either the Ethernet or USB connector.
• If supported by the service provider, two PCs can be connected, one to the Ethernet connector and
the second to the USB connector.
Cisco CVA122/CVA122E Hardware Installation Guide
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Features
NoteFor network performance reasons Cisco recommends a maximum limit of 16 CPE devices.
Voice Ports
Chapter 1Product Overview
• If supported by the service provider, an Ethernet hub can be connected to the Ethernet connector,
and multiple PCs can be connected to the hub.
NoteThe USB specification does not support networking multiple PCs using a USB
bridging hub.
The Cisco CVA122/CVA122E Cable Voice Adapter supports up to 254 PCs (and other CPE devices) in
bridging mode. No maximum limit exists in routing mode. However, the CMTS can impose its own
limitation on the maximum number of PCs and CPE devices.
The service provider may also set a different limit by changing the MAX CPE parameter
in the DOCSIS configuration file—the default MAX CPE value is one CPE device.
The Cisco CVA122/CVA122E Cable Voice Adapter contains two analog (FXS) voice ports at the rear
of the unit. These ports can be connected directly to analog telephones, modems, or FAX devices in the
following ways:
• A single-line telephone, modem, or FAX device can be connected to each voice port, using a
two-wire connection.
• A two-line analog telephone, modem, or FAX device can be connected to the first voice port
(labeled “V1+V2”), using a four-wire cable. When a two-line telephone is plugged into this port,
the second line acts as if it were plugged into the V2 port. If a two-line telephone is used, a device
plugged into the V2 port acts as an extension to the second line of the two-line telephone.
• Adapters can be used to connect multiple analog devices to a single voice port. When multiple
telephones connected to a voice port, they function as extensions.
The Cisco CVA122/CVA122E Cable Voice Adapter supports up to two simultaneous voice connections,
one on each voice port. Only one voice call—telephone, modem, or FAX —per VoIP line is active at a
time. The actual number of voice ports and voice devices supported depends on the services purchased
from the service provider.
CautionDo not connect the voice ports to telephone wires that exit the building under any
circumstances—this is a safety hazard. The Cisco CVA122/CVA122E Cable Voice
Adapter is not designed to connect to the Public Telephone Switched Network (PTSN).
Multiple analog telephone devices can be connected to each of the VoIP telephone lines, provided the
total Ringer Equivalence Number (REN) for all telephones does not exceed the limits given in
Appendix A, “Technical Specifications.”
1-14
NoteA REN value is assigned to each terminal device to denote the percentage of the total load
to be connected to the telephone loop used by the device, to prevent overloading. When
the REN value is exceeded, the telephones might not ring properly or at all.
Cisco CVA122/CVA122E Hardware Installation Guide
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Chapter 1Product Overview
Power Supply
CautionUse only a Cisco-provided power supply and a cord appropriate to the country of
Features
The Cisco CVA122/CVA122E Cable Voice Adapter uses an external AC-input power supply. See
Table A-1 in Appendix A, “Technical Specifications,” for the AC-input power supply power
specifications, including input voltage and operating frequency ranges.
The Cisco CVA122/CVA122E Cable Voice Adapter does not contain a power switch. After the cable
system technician installs, connects, powers on, and initializes the unit, it is intended to remain
connected to the broadband network when operating normally.
The same power supply supports both U.S. and international operation. Different power cords are
required, however, depending on the country of operation.
operation. Using any other vendor’s power supply and cord can cause loss of data or
permanent damage.
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Cisco CVA122/CVA122E Hardware Installation Guide
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Features
Chapter 1Product Overview
1-16
Cisco CVA122/CVA122E Hardware Installation Guide
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