RFC 2428 (rfc2428) - Page 1 of 8
FTP Extensions for IPv6 and NATs
Alternative Format: Original Text Document
Network Working Group M. Allman
Request for Comments: 2428 NASA Lewis/Sterling Software
Category: Standards Track S. Ostermann
Ohio University
C. Metz
The Inner Net
September 1998
FTP Extensions for IPv6 and NATs
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 specification for the File Transfer Protocol assumes that the
underlying network protocol uses a 32-bit network address
(specifically IP version 4). With the deployment of version 6 of the
Internet Protocol, network addresses will no longer be 32-bits. This
paper specifies extensions to FTP that will allow the protocol to
work over IPv4 and IPv6. In addition, the framework defined can
support additional network protocols in the future.
1. Introduction
The keywords, such as MUST and SHOULD, found in this document are
used as defined in RFC 2119 [Bra97].
The File Transfer Protocol [PR85] only provides the ability to
communicate information about IPv4 data connections. FTP assumes
network addresses will be 32 bits in length. However, with the
deployment of version 6 of the Internet Protocol [DH96] addresses
will no longer be 32 bits long. RFC 1639 [Pis94] specifies
extensions to FTP to enable its use over various network protocols.
Unfortunately, the mechanism can fail in a multi-protocol
environment. During the transition between IPv4 and IPv6, FTP needs
the ability to negotiate the network protocol that will be used for
data transfer.
Allman, et. al. Standards Track