User`s guide

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KwikNet Low Level Services
DHCP and BOOTP Operation
The KwikNet DHCP Client automatically requests an IP address for a DHCP enabled
Ethernet network whenever the network interface is opened.
The DHCP client uses UDP datagrams for the transmission of DHCP messages.
Responses are expected to be in UDP datagrams.
The DHCP client broadcasts a DHCP query to all DHCP servers. If the network has been
configured for standard DHCP operation and has been configured with an IP address
other than 0.0.0.0, the DHCP client will request the use of that IP address but accept an
alternate if offered by the DHCP server.
If the network has been configured for DHCP (reboot) operation, it must be configured
with an IP address other than 0.0.0.0. In this case, the DHCP client will demand the use
of that IP address and will accept no other. Note that the broadcast DHCP query looks
like a valid BOOTP query to any server which only supports the older BOOTP format.
Once an IP address offer is received from a DHCP server, the DHCP client responds with
a request to unconditionally accept the offer. If the DHCP server acknowledges the
acceptance of its offer, the DHCP client adopts the IP address thereby making the
network ready for use by the application.
If a BOOTP server responds to the initial DHCP query, the DHCP client simply adopts
the IP address provided by the BOOTP server thereby making the network ready for use
by the application. There is no need for the acceptance and acknowledgment handshake.
The KwikNet DHCP Client does not make use of the server host name or boot file name, if
any, provided in the DHCP or BOOTP server response. To access this information, call
Treck function tfConfGetBootEntry().