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),...