Motorola MVME166IG/D2 - Manual (Page 66)

Debugger General Information
3-20 MVME166 Single Board Computer Installation Guide
3
RARP/ARP Protocol Modules
The Reverse Address Resolution Protocol (RARP) basically consists of an
identity-less node broadcasting a "whoami" packet onto the Ethernet, and
waiting 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 (next paragraph).
BOOTP Protocol 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 Protocol 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 phase is labeled
"address determination and bootfile selection" and the second phase is labeled
"file transfer". The first phase will utilize the RARP/BOOTP capability and the
second phase will utilize the TFTP capability.
Network I/O Error Codes
166Bug returns an error code if an attempted network operation is
unsuccessful.