Subject: Last Call: Feature negotiation mechanism for the File Transfer Protocol to Proposed Standard

From: The IESG <[email-masked]>
Date: Tue, 06 Jan 1998 07:57:36 -0500

The IESG has received a request from the Extensions to FTP Working Group
to consider Feature negotiation mechanism for the File Transfer
Protocol <draft-ietf-ftpext-feat-02.txt> as a Proposed Standard.

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action.  Please send any comments to the
[email-masked] or [email-masked] mailing lists by January 20, 1998.

Files can be obtained via
ftp://ds.internic.net/internet-drafts/draft-ietf-ftpext-feat-02.txt

---

From: "D. J. Bernstein" <[email-masked]>
Date: 8 Jan 1998 18:22:25 -0000

Robert Elz writes:
  [ about changing " " to "211-" in a proposed FTP extension ]
> That's certainly just a cosmetic change,

I'm continually amazed at how little attention the IETF pays to these
basic protocol engineering issues.

In the real world, Qualcomm has just released a version of Eudora Pro
that's incompatible with thousands of non-sendmail SMTP servers around
the world. It fails whenever it tries to send a styled message, because
it incorrectly terminates SMTP lines with \n instead of \r\n. Oops.

Exercise for the reader: How could SMTP have been engineered so that
Qualcomm would not have fallen into this trap? (For some hints, see
http://pobox.com/~djb/proto/design.html. For a complete answer, see
http://pobox.com/~djb/proto/qmtp.txt.)

Back to the proposed extension. I object to FEAT on the grounds that its
response format is much more complicated than it needs to be. The format
should be redesigned to make client parsing as easy as possible. In
particular, the initial text should be scrapped, and the current "\r\n "
separator should be replaced by a single-byte terminator such as "/".

---Dan

P.S. I'm sending this to [email-masked] and [email-masked]. Thanks to
the misguided ftp-wg MLM, ftp-wg subscribers probably won't see the
complete To line.