Tgn (traffic generator) is a command-line based network traffic generator that allows to easily craft and inject network traffic. it has the same packet crafting and injection capabilities provided by the network expect framework but does not have the bigger dependencies that network expect has. the protocol data unit (pdu) to send is defined in a simple way, without the use of complicated command-line switches that are hard to remember.

a tgn invokation may look like:

shell# tgn "ip(proto = 0..255, src = 'random', dst = 192.168.1.1)/icmp-echo()"

visit http://www.netexpect.org for more information.