Compatibility With Bootp; Using A Bootp Relay Agent - Novell NETWARE 6-DOCUMENTATION Manual

Compatibility with BOOTP

Using a BOOTP Relay Agent

When a client loses or ends its lease and is subject to DDNS updates, the DNS
server receives the DDNS update request and deletes the PTR and A records
associated with the client.
DHCP is based on the Bootstrap Protocol (BOOTP) and maintains some
backward compatibility. BOOTP was designed for manual configuration of
the host information in a server database. Novell has extended support for
BOOTP to provide Dynamic BOOTP support. A pool of addresses can be set
up for BOOTP address assignment so that each BOOTP address does not have
to be configured separately.
From the clients' point of view, DHCP is an extension of BOOTP, enabling
existing BOOTP clients to interoperate with DHCP servers without requiring
any change to the clients' initialization software. Some new, additional options
optimize DHCP client-server interaction.
There are two primary differences between DHCP and BOOTP. DHCP
defines methods through which clients receive IP addresses for a specified
period of time, enabling serial reassignment of addresses to different clients.
There is no concept of a lease time in BOOTP; address assignments (even in
Dynamic BOOTP) are permanent. Additionally, DHCP provides a method for
a client to acquire all the IP configuration parameters it requires to operate.
If multiple servers service a single subnet, only one server, the principal server
can be designated as an automatic BOOTP server.
Another difference between the two protocols is a change in terminology to
clarify the meaning of the Vendor Extension field in BOOTP messages. With
DHCP, this field is called the Option field.
A BOOTP relay agent (also known as a forwarder) is an Internet host that
passes DHCP messages between DHCP clients and DHCP servers in a subnet
environment. The forwarder usually resides on an IP router; however, any
Novell server on a subnet can run the BOOTPFWD.NLM. The DHCP service
in Novell DNS/DHCP Services provides relay agent functions as specified in
the BOOTP protocol specification (Internet RFC 951).
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Understanding