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Determine the Available Bandwidth on the BFS for Inband or Out-of-Band Sources
4001182 Rev B
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Determine the Available Bandwidth on the BFS for
Inband or Out-of-Band Sources
Inband or Out-of-Band Sources
Overview
Note: Prior to adding a new inband or out-of-band source, you must determine the
amount of unused bandwidth.
amount of unused bandwidth.
This section provides procedures to determine how much bandwidth is currently in
use on the BFS for inband or out-of-band sources. Use this value to calculate the
amount of unused bandwidth available for the application you want to add to the
BFS. To determine the amount of bandwidth that is available for additional
applications, perform the following calculation:
use on the BFS for inband or out-of-band sources. Use this value to calculate the
amount of unused bandwidth available for the application you want to add to the
BFS. To determine the amount of bandwidth that is available for additional
applications, perform the following calculation:
Total Available Bandwidth - Bandwidth in Use = Unused Bandwidth
Notes:
The inband data rate for a 64 quadrature amplitude modulation (QAM) and 256-
QAM modulator is 27 and 38 Mbps, respectively; this is due to modulation
coding and error corrections (real rates are higher). The total available
bandwidth for each QAM modulator is 25 Mbps and 36 Mbps, respectively; this
is due to the bandwidth reservation on the Broadband Integrated Gateway (BIG)
and the inaccuracy of the data rate control on the DNCS.
QAM modulator is 27 and 38 Mbps, respectively; this is due to modulation
coding and error corrections (real rates are higher). The total available
bandwidth for each QAM modulator is 25 Mbps and 36 Mbps, respectively; this
is due to the bandwidth reservation on the Broadband Integrated Gateway (BIG)
and the inaccuracy of the data rate control on the DNCS.
The out-of-band data rate is 0.35 Mbps. Cisco recommends that you strive to
keep the aggregate out-of-band data rate as low as possible.
keep the aggregate out-of-band data rate as low as possible.
Determining the Available Bandwidth on the BFS
1 From the DNCS Administrative Console, click the DNCS tab, and then click
Utilities. The Utilities window appears in the forefront.
2 Click xterm to open an xterm window.
3 Type cd doctor.
3 Type cd doctor.