Cisco DPC2203C, Installation And Operation Manual

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Theory of Operation
72-4017315-01 Rev B 11
Notes:

If the cable modem does not contain the software version requested by the
configuration file, the cable modem requests that software version from the TFTP
server. When the software installation is complete, the cable modem restarts the
entire initialization process again at the scan for downstream channel stage.

If the system instructs the cable modem to use a different frequency from what
the cable modem is currently using, the cable modem cannot proceed to the next
stage: register with the CMTS. The cable modem must repeat the scan for
downstream channel stage or reestablish ranging on a new upstream channel.
Register with the CMTS
After the cable modem completes the transfer operational parameters stage, the
cable modem now registers with the CMTS. After the cable modem receives a reply
from the CMTS confirming its registration request, the cable modem is now
authorized to forward network traffic from the CPE.
Initialize Baseline Privacy
Baseline Privacy functions in the CMTS and in the cable modem are used to encrypt
data being transferred to and from the cable modem. Following registration with the
CMTS, if the cable modem is provisioned to run with baseline privacy, the cable
modem must initialize baseline privacy operations. Using baseline privacy means
that all data transferred is secure.