TcpCatcher is a free proxy server software, and a great TCP and HTTP(s) monitor. As a developer tool, TcpCatcher will let you debug any client-server application by displaying tcp packets.As an educational tool, TcpCatcher will help understanding any TCP based protocol.Since HTTP has became the most commonly used protocol, TcpCatcher provides a large tool box for helping you debug any HTTP based conversation :
- records all traffic between your browser and the Internet. HTTP packets, often chunked and zipped at network level, are reassembled, their content is deflated and presented in a convenient way
- html, javascript, css contents appears pretty printed and can be easily saved
- xml payload (like SOAP messages) are pretty printed, and loaded in a tree view
- images captured at network level are displayed
- http headers definition pops up
- monitor server response time
Unlike any other tools, TcpCatcher has the great ability of letting you interfere in the communication at proxy level:
- turn on ‘Catch Mode’ and debug step by step the client-server communication, each packet intercepted being friendly editable
- provide your own java hook and apply a programmatic operation on each packets going through