Cisco DPC2203C Installation And Operation Manual page 26

Chapter 1 Introducing the Model DPC2203C VoIP Cable Modem
Establish IP Connectivity
After completing the ranging and automatic adjustments stage, the cable modem
attempts to establish Internet Protocol (IP) connectivity. In this stage, the cable
modem obtains network connection information and a cable modem IP address from
provisioning servers that are located on the network side of the CMTS interface.
The cable modem achieves this connectivity using a protocol called Dynamic Host
Configuration Protocol (DHCP).
Note: If the cable modem fails to establish IP connectivity, it terminates the session
and restarts the initialization process at the scan for downstream channel stage.
Establish Time of Day
After the cable modem establishes IP connectivity, the cable modem requests the
time of day from the network interface. This stage allows the cable modem to know
the system time so that when the cable modem logs an event, it associates a time
with that event.
Note: The cable modem can operate without establishing the time of day; however, it
logs the failure, generates an alert to simple network management protocol (SNMP),
and then proceeds to the next stage. The cable modem periodically repeats this stage
to attempt to establish the time of day.
Transfer Operational Parameters
After the cable modem requests the time of day, the cable modem then requests the
transfer of the cable modem configuration file. The cable modem makes the request
to the Trivial File Transfer Protocol (TFTP) server. The configuration file contains
parameters for how the system operator wants the cable modem to function on the
cable network.
Typical operation parameters for the cable modem include:
Upstream and downstream rate limits

Specific frequencies
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Number of CPE devices
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IP filters
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Port filters
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MAC/LLC filters
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Vendor-specific settings
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Software version installed
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10 72-4017315-01 Rev B