Cisco RF Gateway 1 Modules, Configuration Manual

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Provisioning
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2 In the tree menu, select DTI Config .
3 In the Port Mode drop-down box, select desired port mode (for DTI server
redundancy).
Note: For proper interoperation with the Cisco uBR10K, the correct setting for
Port Mode is Auto Non Revert .
4 In the Primary Port drop-down box, select Primary Port .
Note: For proper interoperation with the Cisco uBR10K, the correct setting for
Primary Port is Port 1 .
Note: Connection to the DTI Server can be verified using the DTI monitoring
capability described in the next section.
5 Configure DTI Offset by entering the desired offset value in the row coincident
with the desired carrier. (Units are DOCSIS ticks/64, which are the same units as
the timing offset value calculated by the CMTS.)
Note: Calibration of the DTI Offset is typically necessary when RFGW-1-D
carriers are added to existing service groups as additional primary channel
capacity (i.e. to implement MxN mac-domains, where M>1). In such service
groups, it is desirable that the CMTS "load-balance" cable modems among M
primary channels. Using load-balancing, the CMTS has the ability to move cable
modems among various DS primaries (statically or dynamically) when one or
another primary channel becomes too heavily loaded. To implement load-
balancing, it will likely be necessary to add DTI Offset values to RFGW-1-D
carriers so that DTI timestamp values embedded in DOCSIS SYNC messages on
these carriers are offset to match those carried on local 5x20 downstreams in the
same mac-domain.