Cisco Cisco IOS Software Release 12.1(3)EC
Cisco uBR7200 Series Dynamic Upstream Modulation
Configuration Tasks
6
Cisco IOS Release 12.1(3a)EC1
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Cisco uBR7200 series has one preconfigured (primary) modulation profile that defines a typical
profile for QPSK modulation. To use the Dynamic Upstream Modulation feature, you must create
a second modulation profile that has a higher modulation scheme than the preconfigured profile.
profile for QPSK modulation. To use the Dynamic Upstream Modulation feature, you must create
a second modulation profile that has a higher modulation scheme than the preconfigured profile.
Configuration Tasks
Configuring Dynamic Upstream Modulation
Command
Purpose
Step 1
Router(config)# configure terminal
Enters configuration mode.
Step 2
Router(config)# cable modulation-profile
iuc fec-tbytes fec-len burst-len guard-t
mod scrambler seed diff pre-len last-cw
uw-len
Creates a modulation profile. A modulation profile is a
collection of six burst profiles sent out in a UCD message to
configure modem transmit parameters for the upstream
message types: request, initial maintenance, station
maintenance, short grant, and long grant.
collection of six burst profiles sent out in a UCD message to
configure modem transmit parameters for the upstream
message types: request, initial maintenance, station
maintenance, short grant, and long grant.
profile = Modulation profile number.
iuc = Interval usage code or upstream burst type. Valid entries
are: initial, long, request, short, or station.
are: initial, long, request, short, or station.
Note
To use this command correctly, enter a
line with all parameters for each upstream
burst type. An incomplete burst profile
causes unreliable operation, or loss of
modem connectivity.
line with all parameters for each upstream
burst type. An incomplete burst profile
causes unreliable operation, or loss of
modem connectivity.
fec-tbytes = The number of bytes that can be corrected per FEC
code word. Valid values are from 0 to 10, where 0 means no
FEC.
code word. Valid values are from 0 to 10, where 0 means no
FEC.
fec-len = FEC code word length. Valid values are from 16 to
253.
253.
burst-len = Maximum burst length in minislots. Valid values
are from 0 to 255, where 0 means no limit.
are from 0 to 255, where 0 means no limit.
guard-t = Guard time in symbols. The time between successive
bursts.
bursts.
mod = Modulation. Valid entries are 16qam and qpsk.
scrambler = Enable or disable scrambler. Valid entries are
scrambler and no-scrambler.
scrambler and no-scrambler.