Re: socket trace

[Jim Langston <jimlangston@xxxxxxxxxxxxxxxx>]

When you wrote your proxy program for FTP did you also remember to proxy
port 20 in addition to port 21?  Port 21 is the telnet session, pretty much
just like telnet.  Port 20 is the actual data file you are sending.

Other than making sure you get the FTP commands right, and send in the right
format on port 20, you should be fine.  I've written quite a number of my own
clients (Telnet, IRC, HTTP, POP3, SMTP) at home using different languages
(Delphi, VBasic and VC++) just for the exercise.  Not really that difficult,
as long as you are not concerned about supporting the complete set of allowable
commands but just a subset.

Good luck!

Regards,

Jim Langston

Gene_Gaunt@ReviewWorks.com wrote:
> 
> Thank you all for the 'middle man' suggestion.  I hadn't thought of that.
> Indeed it was easy for me to write a 'middle man' and redirect my FTP and
> SMTP clients.  Now I have some spooled files of the raw data to study.  Now
> I have fresh copies of the RFC  821 and the RFC 959, and I'm thinking,
> "That's IT?  Where's the beef?"  What are the pros and cons of writing our
> own FTP client to send home brewed X.12 files to a RAS FTP server over a
> PPP dial-up connection?  Are there any gotchas we should consider?
> 
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