User`s guide

KwikNet Low Level Services

DAK

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4.2 DHCP, BOOTP and Auto IP

4.2.1 DHCP and BOOTP

KwikNet includes support for the Dynamic Host Configuration Protocol (DHCP) which

permits an Ethernet network's IP address to be dynamically assigned when the network is

first started. The DHCP Client which implements this service is provided as a standard

feature with systems that only incorporate IPv4. For dual IPv4/IPv6 systems requiring a

DHCP Client, an alternate, optional KwikNet DHCP component is available.

DHCP support is enabled by a configuration parameter in the KwikNet Network Parameter

File used in the construction of the KwikNet Library as described in Chapter 2.3. When

you define your KwikNet configuration, simply check the option box labeled "DHCP Client

support

" on the IPv4 property page.

Once you have enabled DHCP support, KwikNet allows each Ethernet network interface to

be individually DHCP enabled. For a prebuilt network interface, edit your Network

Parameter File, go to the Networks property page and add or edit your Ethernet network

interface description. Click on the Edit: IP Address radio button and select DHCP,

DHCP (reboot) or BOOTP from the pull down list labeled "Runtime configuration:" (see

Chapter 2.4).

For network interfaces that are dynamically created at runtime, your application must

request DHCP support when function kn_ifopen() is called to open the interface.

The KwikNet DHCP Client supports three variants: standard DHCP, DHCP with reboot

and BOOTP. The DHCP options operate identically with one exception. If the reboot

variant is used, the DHCP client will always start the negotiation in the reboot state and

demand that the DHCP server grant the use of the configured IP address. The BOOTP

option uses the older BOOT Protocol to acquire an IP address.

Note

KwikNet does not provide DHCP or BOOTP support for

SLIP or PPP networks.