RFC 906 (rfc906) - Page 1 of 4

Bootstrap loading using TFTP

Network Working Group                                     Ross Finlayson
Request for Comments: 906                            Stanford University
                                                               June 1984

                      Bootstrap Loading using TFTP


Status of this Memo

   It is often convenient to be able to bootstrap a computer system from
   a communications network.  This RFC proposes the use of the IP TFTP
   protocol for bootstrap loading in this case.

   This RFC specifies a proposed protocol for the ARPA Internet
   community, and requests discussion and suggestions for improvements.

Introduction

   Many computer systems, such as diskless workstations, are
   bootstrapped by loading one or more code files across a network.
   Unfortunately, the protocol used to load these initial files has not
   been standardized - numerous methods have been employed by different
   computer manufacturers. This can make it difficult, for example, for
   an installation to support several different kinds of systems on a
   local-area network.  Each different booting mechanism that is used
   must be supported, for example by implementing a number of servers on
   one or more host machines.  This is in spite of the fact that these
   heterogeneous systems may be able to communicate freely (all using
   the same protocol) once they have been booted.

   We propose that TFTP (Trivial File Transfer Protocol) [6] be used as
   a standard protocol for bootstrap loading.  This protocol is
   well-suited for our purpose, being based on the standard Internet
   Protocol (IP) [4].  It is easily implemented, both in the machines to
   be booted, and in bootstrap servers elsewhere on the net.  (In
   addition, many popular operating systems already support TFTP
   servers.)  The fact that TFTP is a rather slow protocol is not a
   serious concern, due to the fact that it need be used only for the
   primary bootstrap.  A secondary bootstrap could use a faster
   protocol.

   This RFC describes how system to be booted (called the "booter"
   below) would use TFTP to load a desired code file.  It also describes
   an existing implementation (in ROM) for Ethernet.

   Note that we are specifying only the network protocols that would be
   used by the booting system.  We do not attempt to mandate the method
   by which a user actually boots a system (such as the format of a
   command typed at the console).  In addition, our proposal does not




Finlayson