Tool used to monitoring of traffic packages on the network
tcpdump -i eth0
tcpdump -n -i eth0
tcpdump -n -i eth0 -w tcpdump01.cap
tcpdump -r tcpdump01.cap | grep http
tcpdump -r tcpdump01.cap | grep UDP
tcpdump -n eth0 icmp and src src 192.168.1.1