Cisco CMTS supports static load balancing for MTC/MRC modems and dynamic load balancing for non-MTC and/or non-MRC modems.
Support for configuration of load balancing groups (LBGs) that entail multiple interfaces, multiple load balancing policies,
and the option to configure multiple additional load balancing parameters are also included.
The load balancing policies can be configured on the Cisco CMTS, indexed by an ID, to limit the movement of cable modems within
a Load Balancing Group (LBG). The cable modem will forward TLV43.1in its registration request (REG-REQ) message, which is
then parsed and stored in the Cisco CMTS. A policy defines whether and when cable modems can be moved within their load balancing
During dynamic load balancing, the specified policy of the cable modem is checked to determine whether the cable modem is
allowed to move.
Load balancing supports Dynamic Channel Change (DCC). DCC in DOCSIS 1.1, dynamically changes cable modem upstream or downstream
channels without forcing a cable modem to go offline, and without re-registration after the change.
Load balancing distributes downstream load balancing with upstream channel loads in the same upstream load balancing group.
This improves upon the prior load balancing limitation, in which load balancing was implemented on the basis of the entire
downstream channel load.
Load balancing uses rules and policies to decide on moving the cable modems within their LB groups. These policies are created
on the Cisco CMTS and chosen on a per-CM basis using type-length-value (TL V) portion (43.1,Policy ID) of REG-REQ. These policies
prohibit a modem from being moved or restricted.
A policy contains a set of rules. When the policy is defined by multiple rules, all rules apply in combinations. A rule can
be defined as "enabled" , "disabled" , or "disabled during time period. " Each rule can be used by more than one policy.
DOCSIS 3.0 static modem count-based load balancing uses the dynamic bonding change (DBC) to modify the following parameters
of DOCSIS 3.0 cable modem with multiple transmit channel (MTC) mode or multiple receive channel(MRC) mode without primary
- Transmit channel set (TCS)
- Receive channel set (RCS)
- Downstream IDs (DSID) or DSID-associated attributes
- Security association for encrypting downstream traffic
These parameters and additional load balancing schemes are supported on the Cisco CMTS, and described in this document. This
document describes all implementations of load balancing on the Cisco CMTS, dependent upon the Cisco IOS release installed
and the desired parameters.
Finding Feature Information
Your software release may not support all the features that are documented in this module. For the latest feature information
and caveats, see the release notes for your platform and software release. The Feature Information Table at the end of this
document provides information about the documented features and lists the releases in which each feature is supported.