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TimeCreator 1000 User’s Guide
097-93100-01 Revision C – February, 2010
Chapter 1 Overview of the TimeCreator 1000
Overview
Shelf
The TimeCreator 1000 shelf requires a minimum of three plug-in modules to
operate:
Power Supply module
Input/Output/Clock (IOC) module
Information Management Card (IMC) module.
It is recommended that a second Power Supply module and IOC are added to the
configuration for redundant operation. Since the TimeCreator 1000 provides the
Master DOCSIS Clock and Timestamp for the entire Headend or Hub site, it is
designed to provide high reliability through redundancy, although redundancy is not
required. The flexibility of configuration and therefore cost enables various
deployment scenarios for root, slave, and protected architectures.
Input Signals
The TimeCreator 1000 can use either GPS or DTI signals as external input
references to acquire the system’s frequency, DTI timestamp, and TOD alignment.
NTP and the user-specified time from the IMC’s real-time clock (RTC) can also
provide system TOD with much less accuracy. See
for descriptions. Only
GPS can provide a common timestamp across the network for a distributed
M-CMTS deployment. It is suggested that all root TimeCreator 1000 servers be
configured with GPS. Upgrading any DTI Server from a user time or NTP time to
GPS for BSoD or distributed M-CMTS architectures will require resetting the
DOCSIS Timestamp and thus re-range all cable modems. The GPS input connects
to the TNC connector on the IMC and the DTI input from a root DTI Server connects
to the rear panel port A and port B RJ-45 connectors (labeled A/11 and B/12). NTP
runs on the IMC’s management Ethernet port.
Note:
When ports A/11 and B/12 are provisioned as outputs, they are
referenced as Ports 11 and 12.