Specifications

3-67
Cisco Cable Modem Termination System Feature Guide
0L-1467-02
Chapter 3 Spectrum Management for the Cisco Cable Modem Termination System
Configuration Examples
• Configures the upstream so that when its noise threshold is reached, it first attempts to change the
frequency, then the channel-width, and finally to switch the modulation profile (using the Dynamic
Upstream Modulation feature).
!
version 12.1
no service pad
no service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname ubr7200
!
!
! Define a frequency band for a 1.6 MHz channel around center frequency of 20.800 MHz
cable spectrum-group 1 band 19750000 21850000 0
! Define a frequency band for a 1.6 MHz channel around center frequency of 23.200 MHz
cable spectrum-group 1 band 22150000 24250000 0
! Hop period set to 30 sec to avoid modems going offline before initiating a hop priority
cable spectrum-group 1 hop period 30
! Percentage of missed station maintenance from modems
cable spectrum-group 1 hop threshold 20
!
cable modulation-profile 1 initial 5 34 0 48 qpsk scrambler 152 no-diff 128 fixed uw16
cable modulation-profile 1 station 5 34 0 48 qpsk scrambler 152 no-diff 128 fixed uw16
! Create second modulation profile numbered 4
cable modulation-profile 4 request 0 16 0 8 qpsk scrambler 152 no-diff 64 fixed uw16
cable modulation-profile 4 initial 5 34 0 48 qpsk scrambler 152 no-diff 128 fixed uw16
cable modulation-profile 4 station 5 34 0 48 qpsk scrambler 152 no-diff 128 fixed uw16
cable modulation-profile 4 short 6 75 6 8 16qam scrambler 152 no-diff 144 shortened uw16
cable modulation-profile 4 long 8 220 0 8 16qam scrambler 152 no-diff 160 shortened uw16
! Create two modulation profiles using the default QPSK and QPSK/16-QAM profiles
cable modulation-profile 3 qpsk
cable modulation-profile 5 mix
!
no cable qos permission create
no cable qos permission update
cable qos permission modems
cable time-server
clock calendar-valid
no ip subnet-zero
no ip domain-lookup
!
!
!
interface FastEthernet0/0
no ip address
no ip mroute-cache
shutdown
media-type MII
full-duplex
!
interface Ethernet1/0
ip address 10.11.10.1 255.0.0.0
no ip mroute-cache
half-duplex
!
interface Cable3/0
ip address 255.255.255.0 secondary
ip address 255.255.255.0
no keepalive
cable map-advance static
cable bundle 1 master
cable downstream annex B