Sniffer
Sniffer - is a computer program or piece of computer hardware that can intercept and log traffic that passes over a digital network or part of a network.
Principle of operation (Polish)
http://magnum34.pl/sniffer-w-pythonie/
Documentation Linux Socket
http://man7.org/linux/man-pages/man7/socket.7.html
List of IP protocol numbers
https://en.wikipedia.org/wiki/List_of_IP_protocol_numbers
Documentation TCP
https://tools.ietf.org/html/rfc793
Documentation TCP/IP
http://www.ietf.org/rfc/rfc1180.txt
License
MIT license. See the LICENSE file for more details.