FTP issues with IPv6-IPv4 translation

[Iljitsch van Beijnum <[e-mail]>]

Here's an update of the FTP64 draft.

It specifies some updates to FTP servers and clients so those can talk  
through IPv6-to-IPv4 translators on their own, but it does allow for  
(not mandate) FTP ALGs to help out unupdated clients/servers. I think  
this is a reasonable tradeoff, please let me know what you think.

I'll be talking about this in the apps area session in Stockholm.

Iljitsch

Begin forwarded message:

> 	Title           : IPv6-to-IPv4 translation FTP considerations
> 	Author(s)       : I. van Beijnum
> 	Filename        : draft-van-beijnum-behave-ftp64-04.txt
> 	Pages           : 9
> 	Date            : 2009-07-09

> The File Transfer Protocol has a very long history, and despite the
> fact that today, other options exist to perform file transfers, FTP
> is still in common use.  As such, it is important that in the
> situation where some client computers are IPv6-only while many
> servers are still IPv4-only and IPv6-to-IPv4 translators are used to
> bridge that gap, FTP is made to work through these translators as
> best it can.

> FTP has an active and a passive mode, both as original commands that
> are IPv4-specific, and as extended, IP version agnostic commands.
> The only FTP mode that works without changes through an IPv6-to-IPv4
> translator is extended passive However, many existing FTP servers
> don't support this mode, and some clients don't ask for it.  This
> document describes the optimal server, client and middlebox (if any)
> behavior to minimize this problem.

> A URL for this Internet-Draft is:
> http://www.ietf.org/internet-drafts/draft-van-beijnum-behave-ftp64-04.txt