Re: Passive sftp?

FTP has become complicated. These are two standards for secure ftp
SFTP and FTPS.

SFTP operates like ssh/scp. It uses the same port (port 22). openssh
supports sftp both client and server.

FTPS operates like ftp and ssl/tls (port 20/21, etc). Among the ftp
clients that now support this addition are gftp and fireftp. vsftpd is
a FTPS server.

On Wed, Mar 5, 2008 at 9:29 PM, Tom Lobato <tomlobato@gmail.com> wrote:
> Bob Rasmussen escreveu:
>
>  > In the FTP protocol, "passive" means that only one connection is
>  > established, originating in the client. All trafic goes over this
>  > connection. (In non-passive FTP, the server opens a second channel back to
>  > the client.)
>  >
>  > No such differentiation exists in SFTP. There is only one connection.
>  >
>  > The vendor may be using "passive" in a different sense, but I don't think
>  > it is a widely accepted usage.
>
>  in really, both passive and active ftp modes uses two connections. The
>  first, which is originated on client (to port 21 on server), is the
>  control connection, for authentication, command/response exchanges, etc.
>  The second connection, which transfer effective data, support two modes:
>   passive: originated from client to server. Uses destination port
>  defined on control connection.
>   active: originated from server to client. Uses destination port 20 on
>  client.
>
>  See http://www.faqs.org/rfcs/rfc1579.html (Firewall-Friendly FTP).
>
>  good resources:
>  http://en.wikipedia.org/wiki/File_Transfer_Protocol
>  http://www.slacksite.com/other/ftp.html
>  http://www.faqs.org/rfcs/rfc959.html (for the braves!)
>
>
>  Tom Lobato
>  www.tinecon.com.br