Ngrepngrep (network grep) is a network packet analyzer written by Jordan Ritter. It has a command-line interface, and relies upon the pcap library and the GNU regex library. ngrep supports Berkeley Packet Filter (BPF) logic to select network sources or destinations or protocols, and also allows matching patterns or regular expressions in the data payload of packets using GNU grep syntax, showing packet data in a human-friendly way. ngrep is an open source application, and the source code is available to download from the ngrep site on GitHub.
WiresharkWireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education. Originally named Ethereal, the project was renamed Wireshark in May 2006 due to trademark issues. Wireshark is cross-platform, using the Qt widget toolkit in current releases to implement its user interface, and using pcap to capture packets; it runs on Linux, macOS, BSD, Solaris, some other Unix-like operating systems, and Microsoft Windows.
EtherApeEtherApe is a packet sniffer/network traffic monitoring tool, developed for Unix. EtherApe is free, open source software developed under the GNU General Public License. Network traffic is displayed using a graphical interface. Each node represents a specific host. Links represent connections to hosts. Nodes and links are color-coded to represent different protocols forming the various types of traffic on the network. Individual nodes and their connecting links grow and shrink in size with increases and decreases in network traffic.
Tcpdumptcpdump is a data-network packet analyzer computer program that runs under a command line interface. It allows the user to display TCP/IP and other packets being transmitted or received over a network to which the computer is attached. Distributed under the BSD license, tcpdump is free software. Tcpdump works on most Unix-like operating systems: Linux, Solaris, FreeBSD, DragonFly BSD, NetBSD, OpenBSD, OpenWrt, macOS, HP-UX 11i, and AIX. In those systems, tcpdump uses the libpcap library to capture packets.
Packet analyzerA packet analyzer, also known as packet sniffer, protocol analyzer, or network analyzer, is a computer program or computer hardware such as a packet capture appliance that can analyze and log traffic that passes over a computer network or part of a network. Packet capture is the process of intercepting and logging traffic. As data streams flow across the network, the analyzer captures each packet and, if needed, decodes the packet's raw data, showing the values of various fields in the packet, and analyzes its content according to the appropriate RFC or other specifications.
