PlugProxy version 2.00

Click here to download Linux/Unix .tgz file
Click here to download Windows .zip file

PlugProxy version 2.00 is a free port forwarder/port debugger implementation released under the Gnu General Public License (GPL)


Chris Longo
Brad Wellington
Kevin A. Burton

What's New with version 2.00?

HTML traffic in PlugProxy

What does it do?

PlugProxy is used to forward data from one TCP port to another. This is commonly referred to as "port forwarding." The purpose of this is to invisibly send a request from one site to another. Another use is to debug or inspect data as it travels through the port forwarder.

For instance, you can set PlugProxy up to listen to port 8080 on your local system and forward all requests on that port to When someone points there browser at http://localhost:8080 they really see

PlugProxy should work with most major protocols. I have verified it to work with HTTP, HTTPS, POP3, SMTP, and Telnet. FTP is a problem, being it uses two ports, one for data (20) and another for the actual protocol (21). If you know your protocols well enough you can find your way around almost any situation. Nothing is stopping you from running multiple copies of this software to handle multiple ports.

After doing a lot of SOAP development I needed a tool to see the XML data being passed over the port. Apache includes a tool that does this but I did not really like the "feel" of it. Here is an example of XML data being forwarded and inspected.

SOAP traffic in PlugProxy

How does it work?

PlugProxy includes a simple to use GUI front end as well as a command line mode which can be used as a high-performance background service.

To launch the GUI just run the proxygui.bat or files supplied with the distribution.

To launch the command line mode run the plugproxy.bat or files supplied with the distribution.

The command line parameters for either version are as follows:

Usage: PlugProxy [-g] host rport lport [-v] [-s] [-h]
Where options are:
         -g run the graphical user interface host set the host system 
         rport set the remote (forwarding) port 
         lport set the local (listener) port             
         -v set verbose mode 
         -s sniff (display) the data passed through the proxy. 
         -h use hexdump format when sniffing (ignored if -s not set)
Example: "PlugProxy 80 8080" Forwards data from port 8080 on 
         the localhost to port 80 on

What is required to run it?

For the GUI version Java2 is required. The command line version will run fine under a Java 1.1 VM.

Does it include source code?

Sure does, full source is included. If you wish to make a change please contact us and we can discuss merging your changes with the original source tree.

Please read the included COPYING.txt file for details on licensing.

Enjoy! I hope you find our work useful.