tcpmon

tcpmon is a lightweight application built using the Java programming language that you can use to monitor the data flow for running TCP connections.

Designed with ease of use in mind, the application is simple and intuitive. Its interface makes no exception, since it only comprises the 'Admin' section, where you can setup a new TCP monitoring connection. This process is rather easy, since there are not many configuration options available.

The local port is used by the client application to connect to the host where tcpmon is installed. This program is actually an intermediate between the client and the server, allowing you to keep an eye on the traffic that the connection generates.

The other two fields, namely server name and port define the address of the target host. What tcpmon does is forward the data it receives from the client to the destination server, records and displays it in its main window.

The captured data is displayed in a separate tab (identified by the port number), where you can view the transfer state (finished or failed), the date and time, the request, the source, the target host, as well as details regarding the connection, server and content type, cache control and the user agent, which usually is a browser.

Optionally, you can use the SSL protocol to secure the connection, especially if the transmitted data contains private information. The monitoring process can be stopped at any time and you can submit the data to the server with a button's push.

tcpmon is capable of monitoring several connections at the same time and display traffic information about each one. Although simple, it provides you with a handy tool for TCP monitoring.