Chapter 14: Cable-side Configuration
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
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When a topology change occurs where the MD-CM-SG-ID changes for the fiber node, the MD-CM-SG-ID will be updated for
each modem associated with the fiber node via the fiber node name.
The MD-CM-SG-ID will be zero when the fiber node configuration for the fiber node associated with the modem is no
longer valid. It will be restored when the fiber node is restored to a valid configuration.
Note: Only channels that are operationally in service will be considered for the modem’s RCS and TCS at modem
registration or for DBC load balancing or AC power restoral.
Topology changes that may impact the MD-CM-SG-ID for a fiber node include:
Shutting down or restoring channels in its service group
Adding or removing channels to its service group (fiber node)
Adding or removing channels to a MAC domain
Removing the service group (deleting the fiber node)
Recommended Procedures for Topology Changes
The following procedures and guidelines are suggested when making various changes to topology:
Channel Set Changes within the Fiber Node
When only the channel sets within fiber nodes are changing and the fiber node names are maintained, modify the
existing fiber nodes without deleting the fiber nodes.
This allows the modems that are already registered within the effected fiber nodes to properly select from the
modified MD-CM-SG for DBC load balancing and AC power restoral. (See CM Channel Reassignment for AC Power Loss
for more information.)
Fiber Node Name Changes or Fiber Node Moves
When the fiber node names change for existing fiber nodes, the fiber nodes must be deleted and re-entered with the
new channel sets.
When fiber nodes are moved to a set of channels that are no longer accessible by the modems that were associated
with the fiber node, the fiber nodes must be deleted and re-entered with new channel sets.
When fiber nodes are deleted, the registered modems are no longer able to recover from AC power loss, nor are they
able to be DBC load balanced until the modems are reset.
One of the following options should be considered when changing the fiber node’s name if DBC load balancing or the
AC Power Loss feature is enabled:
