C H A P T E R
5-1
Cisco uBR10012 Universal Broadband Router Software Configuration Guide
OL-1520-05
5
Configuring Basic Broadband Internet Access
This chapter describes the parameters of configuring and maintaining basic broadband Internet access.
The chapter contains these sections:
•
“Overview of Basic Broadband Internet Access” section on page 5-1
•
“Recommended Basic Configuration for High-Speed Internet Access” section on page 5-2
•
“Basic Internet Access Sample Configuration File” section on page 5-3
Overview of Basic Broadband Internet Access
A Cisco uBR10012 router and an intermediate frequency (IF)-to-radio frequency (RF) upconverter are
installed at the headend or distribution hub to transmit digital data. The Cisco uBR10012 router
downstream ports transmit IF signals to the upconverter, which translates the downstream signals to RF
for broadcast.
Receivers, scramblers, and descramblers then process the TV signals to encode or decode signals as
needed for broadcast. Modulators format the analog TV and digital signals.
The analog and digital signals then pass through the RF combiner. The signals are broadcast from the
headend through optical transmitters to fiber nodes.
Amplifiers, coaxial cable, and taps carry the signals to the subscriber premises. Signals are processed as
follows:
•
Tuners that handle MPEG video, audio, and broadcast services in set-top boxes (STBs), TVs, and
VCRs receive one-way analog signals.
•
CMs receive digital data signals:
–
Two-way CMs transmit RF signals back through amplifiers to optical fiber receivers at the
headend. These receivers pass the upstream signal to upstream ports on the
Cisco uBR10012 router, where they are processed.
