RFC 2347 (rfc2347) - Page 1 of 7
TFTP Option Extension
Alternative Format: Original Text Document
Network Working Group G. Malkin
Request for Commments: 2347 Bay Networks
Updates: 1350 A. Harkin
Obsoletes: 1782 Hewlett Packard Co.
Category: Standards Track May 1998
TFTP Option Extension
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Abstract
The Trivial File Transfer Protocol [1] is a simple, lock-step, file
transfer protocol which allows a client to get or put a file onto a
remote host. This document describes a simple extension to TFTP to
allow option negotiation prior to the file transfer.
Introduction
The option negotiation mechanism proposed in this document is a
backward-compatible extension to the TFTP protocol. It allows file
transfer options to be negotiated prior to the transfer using a
mechanism which is consistent with TFTP's Request Packet format. The
mechanism is kept simple by enforcing a request-respond-acknowledge
sequence, similar to the lock-step approach taken by TFTP itself.
While the option negotiation mechanism is general purpose, in that
many types of options may be negotiated, it was created to support
the Blocksize option defined in [2]. Additional options are defined
in [3].
Packet Formats
TFTP options are appended to the Read Request and Write Request
packets. A new type of TFTP packet, the Option Acknowledgment
(OACK), is used to acknowledge a client's option negotiation request.
A new error code, 8, is hereby defined to indicate that a transfer
Malkin & Harkin Standards Track