Nstreams is a utility designed to identify the IP streams that are occurring on a network from a non-user friendly tcpdump output of several megabytes. This is especially useful when you plan to install a firewall but if you do not know the nstreams that the network users are generating (http, real audio, and more...).

Nstreams can read the tcpdump output directly from stdin, or from a file. It can even generate the configuration file of your firewall.