Scapy is a powerful interactive packet manipulation program. It is able to forge
or decode packets of a wide number of protocols, send them on the wire, capture
them, match requests and replies, and much more.

It can easily handle most classical tasks like scanning, tracerouting, probing,
unit tests, attacks or network discovery (it can replace hping, 85% of nmap,
arpspoof, arp-sk, arping, tcpdump, tethereal, p0f, etc.).

It also performs very well at a lot of other specific tasks that most other
tools can't handle, like sending invalid frames, injecting your own 802.11
frames, combining technics (VLAN hopping+ARP cache poisoning, VOIP decoding on
WEP encrypted channel, ...), etc.