User`s manual

Network I/O Support
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1
RARP and ARP Modules
The Reverse Address Resolution Protocol (RARP) basically consists
of an identity-less node that broadcasts a ÒwhoamiÓ packet onto the
Ethernet and waits for an answer. The RARP server fills an Ethernet
reply packet up with the target's Internet Address and sends it.
The Address Resolution Protocol (ARP) basically provides a
method of converting protocol addresses (e.g., IP addresses) to
local area network addresses (e.g., Ethernet addresses). The RARP
protocol module supports systems which do not support the
BOOTP protocol (refer to BOOTP Module below).
BOOTP Module
The Bootstrap Protocol (BOOTP) basically allows a diskless client
machine to discover its own IP address, the address of a server host,
and the name of a file to be loaded into memory and executed.
TFTP Module
The Trivial File Transfer Protocol (TFTP) is a simple protocol to
transfer files. It is implemented on top of the Internet User
Datagram Protocol (UDP or Datagram) so it may be used to move
files between machines on different networks implementing UDP.
The only thing it can do is read and write files from/to a remote
server.
Network Boot Control Module
The control capability of the Network Boot Control Module is
needed to tie together all the necessary modules (capabilities) and
to sequence the booting process. The booting sequence consists of
two phases. The first is address determination and bootfile
selection, and the second is file transfer. The first phase utilizes the
RARP/BOOTP capability and the second phase utilizes the TFTP
capability.