spit is a moduler packet constructor/transmiter/sender, where each module is a protocol layer this allow the user full control over the content of each layer in transmited packets. it here to allow pepole to use it and add modules as they want.
Homemade Packet Constructor is intended to be a powerful tool for network exploration. Using this program you will be able to send custom TCP/UDP/ICMP packets and read the response.The user interfaces is designed in a modular way.