Spectrum Management - Cisco uBR10012 Software Configuration Manual

Supported Software Features for the Cisco uBR10012 Router

Spectrum Management

Spectrum management is a software and hardware feature provided in the CMTS so that the CMTS may
sense both downstream and upstream plant impairments, report them to a management entity, and
automatically mitigate them where possible. Spectrum management provides many capabilities that are
described further in the
Advanced Spectrum Management Support on the Cisco uBR10012 CMTS
Cisco IOS release 12.3(13a)BC introduces Advanced Spectrum Management for the Cisco uBR10012
router, with the following enhancements:
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Commands for Enhanced Spectrum Management
A variety of commands for enhanced spectrum management now provide new options.
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Cisco uBR10012 Universal Broadband Router Software Configuration Guide
1-78
Cisco Cable Modem Termination System Feature
Supports additional software functionality for the Cisco uBR10-LCP2-MC16C/E/S cable interface
line card and the Cisco MC5x20S/U broadband processing engine.
Supports spectrum analyzer functionality.
Supports proactive channel management and hopping decisions, so as to avoid the negative impact
of ingress noise, and to maintain uninterrupted subscriber service.
Offers flexible configuration choices, allowing MSOs to determine the priority of the actions to be
taken when ingress noise on the upstream channel exceeds the allowable thresholds. The
configurable actions are frequency hopping, switching the modulation profile, and reducing the
channel width.
Performs Cisco Network Registrar (CNR) calculations using DSP algorithms in real-time on a
per-interface and a per-modem basis.
Intelligently determines when to modify the frequency, channel width, or modulation profile, based
on CNR calculations in the active channel, the number of missed station maintenance polls, and the
number of correctable or non-correctable Forward Error Correction (FEC) errors. Previously,
channel hopping occurred when the number of missed station maintenance polls exceeded a
user-defined threshold or the SNR reported by the Broadcom chip exceeded the DOCSIS thresholds.
Enhances the Dynamic Upstream Modulation feature for the Cisco uBR-MC16S line card. This
feature supports dynamic modulation using two upstream profiles. The primary profile (typically
using 16-QAM or a mixed modulation profile) remains in effect at low noise conditions, but if
upstream conditions worsen, the cable modems switch to the secondary profile (typically using
QPSK modulation) to avoid going offline. When the noise conditions improve, the modems are
moved back to the primary profile.
cable upstream n threshold cnr-profile1 threshold1-in-dB cnr-profile2 threshold2-in-dB
corr-fec fec-corrected uncorr-fec fec-uncorrected
cable upstream n upstream threshold snr-profiles threshold1-in-dB threshold2-in-dB
cable upstream n threshold corr-fec corrfec-threshold
cable upstream n threshold uncorr-fec uncorrfec-threshold
show cable hop n upstream history
show cable hop n upstream threshold
Chapter 1 Overview of Cisco uBR10012 Universal Broadband Router Software
Guide.
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