Configuring Headend Broadband Access Router Features
Managing Cable Modems on the HFC Network
MC-587
Cisco IOS Multiservice Applications Configuration Guide
Verifying Cable Modem Authentication
To verify whether cable modem authentication has been activated or deactivated, enter the more
system:running-config command and look for the cable interface configuration information. If cable
modem authentication has been activated, it does not appear in this output. If cable modem
authentication has been deactivated, it appears in this output as
no cable secret-shared 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
no cable secret-shared
cable insertion-interval 150000
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
Troubleshooting Tips
To troubleshoot the configuration, perform the following tasks:
• Make sure you entered the correct slot and port numbers when you entered cable interface
configuration mode.
• Verify that the cable modem is using BPI and that it is assigned to a QoS with privacy active.
• Verify that the cable modem configuration file contains a matching key.
Note The DOCSIS configuration file editor cannot reread the key from a completed file because
it would violate the security design.
Activating Cable Modem Upstream Address Verification
Cable modem upstream address verification ensures that only known cable modems that have received
DHCP leases through the Cisco uBR7200 series can access the HFC network. The Cisco uBR7200 series
will discard all packets received for or from hosts that have not received DHCP-assigned addresses.
Command Purpose
CMTS01(config-if)# cable shared-secret [0 | 7]
authentication-key
Enables cable modem authentication. The number 0
specifies that an unencrypted authentication key
follows; the number 7 specifies that an encrypted
authentication key follows.
