tcpflow is a program that captures data transmitted as part of TCP connections (flows), and stores the data in a way that is convenient for protocol analysis or debugging. tcpflow understands TCP sequence numbers and will correctly reconstruct data streams regardless of retransmissions or out-of-order delivery. Each stream is stored in a separate file for later analysis. tcpflow is designed to be portable, using the LBL packet capture library and GNU autoconf. It works under most UNIX platforms and for most common network interface types (ethernet, PPP, loopback, etc.).
