user manual

Configuring Headend Broadband Access Router Features
Managing Cable Modems on the HFC Network
MC-589
Cisco IOS Multiservice Applications Configuration Guide
modem to join the network is known as initial ranging. The default insertion interval setting (automatic)
configures the Cisco uBR7200 series to automatically vary the initial ranging times available to new
cable modems that attempt to join the network.
Note Use the default setting if a large number of cable modems might attempt to perform initial
ranging at the same time; for example, after a major power failure.
To configure the cable modem insertion interval, use one of the following commands in cable interface
configuration mode:
To ignore any minimum or maximum insertion intervals and return to the automatic setting, enter the no
cable insertion-interval command.
Verifying Cable Modem Insertion Interval
To verify that a cable modem insertion interval has been set, enter the more system:running-config
command and look for a notation in the cable interface configuration information as shown in this
command output excerpt:
CMTS01# more system:running-config
Building configuration...
Current configuration:
!
interface Cable6/0
ip address 1.1.1.1 255.255.255.0
no keepalive
cable insertion-interval 2000
cable downstream annex B
cable downstream modulation 64qam
cable downstream interleave-depth 32
cable downstream symbol-rate 5056941
cable upstream 0 frequency 15008000
cable upstream 0 fec
cable upstream 0 scrambler
no cable upstream 0 shutdown
Command Purpose
CMTS01(config-if)# cable insertion-interval automatic
or
CMTS01(config-if)# cable insertion-interval min msec
or
CMTS01(config-if)# cable insertion-interval max msec
Configures the Cisco uBR7200 series to automatically
vary the initial ranging times available to new
cable modems that attempt to join the network.
Sets the minimum insertion interval in milliseconds
(ms). Valid minimum range is from 25 to 200 ms.
Default = 50 ms.
Sets the maximum insertion interval in milliseconds.
Valid maximum range is from 500 to 2000 ms.
Default = 2000 ms.