Feature Request: On the fly compression

[drofekawp]

A nice feature to offer would be on the fly compression between client and server. Something like new HTTP servers and browsers do currently with web content.

Bandwidth savings could be pretty immense depending on the file types (images obviously won't compress much at all )

What's the verdict?

[drofekawp]

In CuteFTP Pro there's an option under SSH2 security that allows you to configure zlib compression on the outbound payload. This could be created as a separate feature, for non secure transfers in FileZilla?

[xaminmo]

This is in 2.2.7a with options:
A) do not compress
B) Compress directories only
C) Compress all files

I've submitted a request for another option to compress dirs and ascii files, but not binary, which would yield the best results IMHO.

[thorin]

The verdict is it's done:

From the Server 0.9.0 release notes:

new features:
- MODE Z file transfer compression

From the Client 2.2.7 release notes:

New features:
- MODE Z file transfer compression

[botg]

Btw, a lot of other FTP clients and servers do already support MODE Z or will support it in the near feature.

[TheAngryPenguin]

Btw, a lot of other FTP clients and servers do already support MODE Z or will support it in the near feature.

I've been playing around with 0.9.0/2.2.7's compression recently -- is it normal that the transfer rate and percentage complete values are totally inaccurate?

-TheAngryPenguin

[thorin]

That would kind of make sense since the compression ratio will vary file to file. The progress calculation is probably based on the original (file system) filesize and the amount of data transmitted/received.

Thorin

[botg]

Yes, it's still based on original file size (anything else makes no sense)

Thus the transferspeed may even appear hight than the best physical transfer speed possible for 'simple' (easy to compres) files.

If FZ would use the physical speed as measurement for compressed transfers, a lot of problems would arise. Especially if the file contents change dramatically during the transfer. Timeleft indicator would present total bogus values in that case.

[TheAngryPenguin]

I understand that it's nearly impossible to have an accurate count, but with a solid and stable 192KBps connection, at best, I've notiched FileZilla showing 2KB/s and the estimated time to finish the transfer is typically months, if not years. To me, this would seem to be very confusing to the average user who doesn't quite grasp how compression works with FTP -- it might give then a false sense that FZ is slower than it actually is.

[botg]

Using compression, in the very worst case, transfer speed should only slow down by 0.03 percent. So if it displays something extremely low, than transfer is really low.

I've just checked it on my machine, displayed transfer speeds are working properly