Cisco 7246 - uBR Router, Руководство по установке оборудования

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Cisco uBR7200 Series Universal Broadband Router Hardware Installation Guide
OL-5421-03
Chapter 2 Preparing the Cisco uBR7200 Series Router for Installation
Provisioning the Cable Headend
•
Upstream ports are configured as appropriate to support frequency agility.
• Downstream frequencies are assigned.
•
Internet connectivity is established.
• Internet addresses are obtained and allocated.
•
All RF connectivity is verified.
Note
For a VoIP system using H.323, ensure that the CMTS has been properly provisioned with equipment
such as VoIP gateways and gatekeepers. For SGCP-based VoIP systems, ensure that the CMTS has been
properly provisioned with equipment such as VoIP gateways and call-agents.
Headend Certification
The cable headend plant must pass both analog and digital certification:
•
In the United States, the Federal Communications Commission (FCC) mandates minimum technical
performance requirements for cable systems.
• For international requirements, consult with local agencies for certification requirements.
The digital certification process is described in Chapter 4, “Connecting the Cisco uBR7200 Series
Router to the Cable Headend.”
IF-to-RF Upconverter
To be compatible with cable television system frequency division multiplexing, install an external
IF-to-RF upconverter that translates the Cisco uBR7200 series cable interface line card downstream IF
signal to the desired downstream RF carrier frequency.
Upconverters are available from many manufacturers and can be found in configurations ranging from a
fixed number of ports to flexible multislot, multiport models. Install and configure enough upconverter
ports to support the number of downstream cable interface card ports installed in each Cisco uBR7200
series router you are installing. The number of upconverter units needed depends on the upconverter
manufacturer.
Appendix F, “Manufacturers for Headend Provisioning Requirements,” lists upconverter
manufacturers, websites for more information on upconverter products, and models of upconverters that
are compatible with the Cisco uBR7200 series router.
The upconverter is installed between the Cisco uBR7200 series router and the combiner. (See Figure 4-3
on page 4-5 and Figure 4-4 on page 4-6 .)
Depending on the channel plan you are employing, your upconverters must support different
functionality. In a North American channel environment, your upconverter needs to receive a 44-MHz
downstream IF transmission from cable interface line cards in the Cisco uBR 7200 series router and
transmit 6-MHz RF digitally modulated carriers in the 88 to 860 MHz range. In an 8-MHz EuroDOCSIS
environment, your upconverter needs to receive a 36.125-MHz downstream IF transmission from cable
interface line cards in the Cisco uBR7200 series router and transmit 8-MHz RF digitally modulated
carriers in the 108 to 862 MHz range.
Refer to the documentation that ships with your upconverter for details on upconverter operation and
configuration. See the
“Connecting and Configuring the Downstream” section on page 4-4 .