Chapter 29: Security
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
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Table 103.
RADIUS Default Values
Command
Keyword
Description
Default
Group
RADIUS Server Group Name
default
Host
IP address of RADIUS Server
None
Key
Shared Secret
None
[hidden]
Specifies whether the specified key is encrypted using the hexadecimal format.
None
Auth-port
RADIUS server’s UDP port number for authentication
1812
Timeout
Time in seconds the C4/c CMTS waits for a response from the server before attempting a
retransmission.
5
Retransmit
Number retransmissions before C4/c CMTS declares the server unreachable.
3
RADIUS Access Challenge
Access Challenge is a component of the RADIUS Authentication protocol; it is sometimes called Password Challenge. In a
network in which RADIUS is enabled, the C4/c CMTS is a client of the RADIUS server and functions as a Network Access
Server (NAS). In earlier releases, the C4/c CMTS did not process Access Challenge packets; instead it simply treated them as
Access Reject packets. With Access Challenge enabled, the NAS prompts the user for more information. This challenge to
the user can be configured as one or more steps. One MSO, for example, requires a three-step process: the user must first
enter 4-8 alphanumeric PIN, then correctly re-enter this PIN, and finally must enter a passcode. If all three steps of the
challenge are completed successfully, then the RADIUS server returns an Access Accept packet and allows the user access
to the NAS, in this case, the C4/c CMTS. If the user fails authentication for more than the allowed number of login
attempts, which is currently set to five, then the telnet session is dropped.
Attributes in the Access-Request Packet
If the associated line from the CER is configured for authentication, then the C4/c CMTS prompts the user for a user ID and
password. The responses are transmitted in the User Name and Password attributes.