Chapter 22: Channel Bonding
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
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They do not specify the receive channel connected offset parameter (RCC Encodings Type 48.5.3).
If the algorithm fails to find a suitable RCC or if the CM has a single channel RCS, the CM registers as non-bonded. Each RCC
is checked starting with the largest number of receive channels. Channels will then be checked to determine which
channels are compatible with the CM’s service flows. If the operator is using attribute masks, then the MD-DS-SG channels
must be evaluated to determine if they can be used to support the CM's provisioned service flows. Many algorithms are
available to sort the channels, but the required end result is that at least one channel must exist in the CM's MD-DS-SG
that satisfies the requirements of each service flow. Also, any channel that cannot be used for any of the CM's service
flows must be removed from consideration. If no channels are found that satisfy the attribute mask requirements, then the
C4/c CMTS must select a channel to provide service anyway, record an event, and update the MIB.
For example, an EMTA might have a voice service flow that is specified to be high availability and low latency as well as a
best effort service flow without any restrictions. At least one DS channel within the CM's MD-DS-SG must satisfy the high
availability and low latency requirements of the voice service flow, or an error will be logged. The remainder of the CM's
MD-DS-SG channels can still be considered for inclusion in the RCC to support the best effort data flow since that flow did
not impose any conditions. If the best effort flow had been specified to utilize only high availability links, then any channels
whose high availability bit is not set to 1 must be removed from consideration for the RCC.
If no channels are found that meet the restrictions of the attribute masks, DOCSIS allows the C4/c CMTS to select one or
more channels to provide service arbitrarily, in which case an error is logged. This algorithm suggests choosing a single
channel to provide service. An alternative algorithm would be to disregard the attribute masks entirely and allow the
largest possible channel set. Once the desired channel list is determined, the system must either use an existing RCC, or
create a new one. If only static RCCs are enabled, the system must choose the RCC that best fits the desired channel set.
Note: If the user has not created an RCC corresponding to this modem's RCP and MAC domain, then this modem can still
register but not as a bonded modem. If the system can create dynamic RCCs, then a best fit channel set will be selected.
Bonding group sizes do not need to match the CM's RCP connection capability attributes.
The frequency range available for bonding group channel selection is dependent on the CM's receive module architecture.
A typical DOCSIS RCP architecture with a single RM will limit the spectrum to the 10 channels, starting with the RCC's First
Channel Center Frequency attribute. The specific spectrum range is determined by the RM’s Adjacent Channels and the
RM’s Center Frequency Spacing definitions. A multiple RM design will have multiple frequency blocks and the RCC will
contain First Channel Center Frequency attributes for each of the RMs that have channels assigned to them. It is perfectly
valid to have RMs to which no receive channels have been assigned. In addition, the MULPI specification states that "A
C4/c CMTS is expected, but not necessarily required, to assign Receive Channels connected to a Receive Module that
