Inova Solutions OnTime 4-Digit Digital Clocks, Installation And User Manual

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IT Groups that use DHCP to assign IP Addresses often use DHCP options to
configure PCs and other devices on the network. Typical examples of these
options are:
DHCP Option 1 to specify the subnet mask.
DHCP Option 3 to specify the router that is the default gateway.
DHCP Option 6 to specify the DNS Server.
When PCs and other devices come up on the network, all of these parameters are
set automatically if they are configured at the DHCP Server. In addition, any
institutional changes will automatically convey to the devices when they restart.
DCHP options in the range of 224 to 254 are reserved for private use for site
specific purposes by RFC 3942. This means that DHCP servers will not pre-
assign them in the way that options in the range of 1 to 223 are pre-assigned (i.e.,
Option 3=Router). Private options are intended for whatever site specific use the
controlling IT Group may have in mind.
The OnTime clock takes advantage of one of the private option slots to enable
plug and play installation of clocks. The OnTime clock is preset to request its
local configuration from the DHCP server using private option 230. If option 230
is set up on the DHCP Server with a valid configuration string, then the clock can
configure itself automatically.
This option reduces the work required to configure multiple clocks, because
rather than configuring each individual clock though a telnet session, the
configuration is done one time at the DHCP server.
DHCP Server changes are typically made by the IT Group.