Nemesis is a command-line network packet injection utility for UNIX-like and Windows systems. You might think of it as an EZ-bake packet oven or a manually controlled IP stack. With Nemesis, it is possible to generate and transmit packets from the command line or from within a shell script. Nemesis is developed and maintained by Jeff Nathan
Nemesis can natively craft and inject packets for :
Using the IP and the Ethernet injection modes, almost any custom packet can be crafted and injected.
Latest Release : Nemesis 1.4beta3