Installation guide

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Cisco uBR7100 Series Universal Broadband Router Software Configuration Guide
OL-2238-03
Chapter 2 Configuring the Cisco CMTS for the First Time
Using the Setup Facility for Cable Interfaces
The digital carrier frequency is specified to be the center of a 6 or 8 MHz channel based on your
channel plan. For NTSC channel plans, EIA channel 95 spans 90.00 to 96.00 MHz. The center
frequency is 93.000 MHz which is the digital carrier frequency that should be configured as the
downstream frequency.
Tip The digital carrier frequency is not the same as the video carrier frequency. For EIA channel 95, the
video carrier frequency is 91.250 MHz which is 1.75 MHz below the center frequency.
• Activating the downstream port on the cable modem card for data transmission over the HFC
network, using the following command:
Router (config-int) # no shutdown
The particular downstream port LED should light.
• Setting the upstream frequency of your RF output to comply with the expected input frequency of
your Cisco cable interface.
Tip The valid range for a fixed upstream frequency is 5,000,000 to 65,000,000 Hz for the cable modem card.
The valid range for the Cisco uBR7100 series is 5,000,000 to 42,000,000 Hz.
The cable interface will not operate until you either set a fixed upstream frequency or create and
configure a spectrum group. Enter the fixed center frequency for your upstream RF carrier in Hz and
specify a port number from 0 to 5:
Router (config-int) # cable upstream port frequency up-freq-hz
Note Ensure that the selected upstream frequency does not interfere with the frequencies used for any
other upstream applications in your cable plant.
• Enter an upstream RF carrier frequency for each upstream port on a cable modem.
• Activate the RF carrier on each upstream port to support data from cable modems or set top boxes
on your network to the Cisco uBR7100 series CMTS. Enable upstream data traffic, using the
following command:
Router (config-int) # no cable upstream port shutdown
The specified upstream port LED lights.
Enter the previous command for each upstream port that you wish to activate.
• Verify your settings using the following command:
Router# show running-config
• Save the configuration to nonvolatile random access memory (NVRAM) so that your settings are
retained after a power cycle:
Router# copy running start
• Verify the upstream frequency, using the show controllers cable slot/port upstream command for
the upstream port that you have just configured.
• Verify the downstream center frequency, using the show controllers cable slot/port downstream
command for the downstream port that you have just configured.