netsniff-ng

What netsniff-ng is

netsniff-ng is a free, open-source Linux network analyzer and toolkit for network development, debugging, analysis, auditing, and reconnaissance. It captures, analyzes, replays, and redirects traffic using zero-copy packet mechanisms, with live and command-line capture as well as offline trace analysis. It reads and writes tcpdump-capable pcap, including nanosecond-resolution pcap, Alexey Kuznetzov's pcap, and netsniff-ng pcap; its capture files interoperate with other packet-analysis tools. Filtering includes low- and high-level options, including Berkeley Packet Filter expressions. The built-in dissector covers Ethernet, WLAN, ARP, MPLS, VLAN, LLDP, IPv4, IPv6, ICMP, IGMP, TCP, and UDP. The toolkit also includes trafgen, mausezahn, ifpps, curvetun, astraceroute, flowtop, and bpfc. Mausezahn and curvetun are marked experimental and not recommended for production use. It is licensed under GNU GPL 2.0. The project provides release-verification instructions and directs questions to its mailing list and FAQ, while noting that it does not guarantee the tools are bug-free.