A new protocol would be good

[Jonathan Morton]

>File transfers shouldn't be part of the VNC protocol at all IMHO.  You just
>need an FTP client embedded into the viewers.  There are free FTP servers
>for windows and unix.

The reason I am interested is because I am behind a firewall which blocks
FTP (among other things), and the only way to get round it is to use PASV
ftp on a non-standard port.  This is decidedly ugly to set up, even on a
pair of Linux boxes, and may not be possible at all on other platforms.

I do agree that the FTP (in PASV mode) protocol is a good one to embed, and
it should need little modification save a UI - but UI is entirely what VNC
is about, so it should be little problem :).  Use a file selector box on
the server end and client end alike - the server end will be visible
through VNC of course.  The actual FTP control and data packets need not be
on a separate TCP link but could be embedded in RFB messages, obviating the
need to open multiple ports on a firewall or struggle with obscure
FTP-client options.  Also, the RFB packets in turn could be wrapped in Zlib
- automatic on-the-fly compression anyone?

There is a non-firewall application for this, too - in technical support,
it may be necessary to send files to the user to solve a problem.  Instead
of launching a program on the user's machine (FTP client, FTP server,
browser etc.) to transfer the file, a clean, simple file transfer over the
VNC link could well be more convenient at both ends.

Care does need to be taken that this extra feature doesn't bloat the client
or server.  However, I estimate that it would add perhaps less than 32K to
the Mac server (which is already about 500K) and similarly to the client.
Existing FTP clients for Windows, I have noticed, tend to be large,
cumbersome, and confusing without exception - because they need to be
powerful enough to communicate with long-obsolete systems.  Fetch (for
Macintosh) is much leaner but still technically overkill for simple file
transfers...

As it happens, the Mac version would need the most care, as Mac files have
much more information attached to them (including two separate data forks)
than other filesystems.  The ability to transfer 'stripped' files between a
Mac and a PC is important to maintain, as well as 'full' files between
Macs.  Standards already exist for packing Macintosh files into a single
bytestream, fortunately.

***aaarrggghhh***  i'm rambling too much now, i need more sleep.  Best
treat this as 'food for thought' for now...

--------------------------------------------------------------
from:     Jonathan "Chromatix" Morton
mail:     chromi "at" cyberspace.org  (not for attachments)
uni-mail: j.d.morton "at" lancaster.ac.uk

The key to knowledge is not to rely on people to teach you it.
--------------------------------------------------------------
Contributing to the VNC Project - http://www.uk.research.att.com/vnc/
Macintosh VNCserver v3.3.2 beta2.2 now posted at:
	http://chromatix.autistics.org/vnc/



---------------------------------------------------------------------
To unsubscribe, send a message with the line: unsubscribe vnc-list
to majordomo "at" uk.research.att.com
See also: http://www.uk.research.att.com/vnc/intouch.html
---------------------------------------------------------------------