Re: Client to telnet into server and then ftp to another server


Gordon Beaton wrote:
On 8 Aug 2006 03:23:30 -0700, Marlo wrote:
I am trying to write a java client that connects to a ftp server.
The trick is that the ftp server has a private IP and is sitting
behind a Telnet server with a public IP address.

How can I go about implementing this client? [I already have the ftp
client working.]. The idea is first to connect via telnet, then
connect to the ftp server and then download/upload files.

I know this isn't a direct answer to your question, but it might help
you find a better solution to your problem.

It sounds to me like you're trying to transfer files between two
hosts, neither of which is your localhost. It might be worth knowing
that the FTP protocol already supports this kind of transfer, i.e. an
FTP client on one host can be used to transfer files directly between
two other hosts, without the files passing the client host.

All that's required is that the client establish control connections
to each of the remote hosts. It's described in the RFC, in particular
figure 2 and section 5.2.

/gordon

--
[ don't email me support questions or followups ]
g o r d o n + n e w s @ b a l d e r 1 3 . s e

Thanks for your reply. I came accross this website,
http://www.rfc-archive.org/getrfc.php?rfc=1415, which I think is the
one you were referring to. I am not familiar with the FTAM protocol. So
I will have to really read up on it to determine whether I can
implement this option.

Question : FTAM does not seem like a very popular protocol. How
difficult do you think will it be to program the FTP-FTAM gateway for a
java developer like me, with 1 year's experience? Bearing in mind that
I have less than a month to familiarise myself with this specification
and to code it?

.

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