Wireshark

Wireshark is the world’s foremost and widely-used network protocol analyzer. It lets you see what’s happening on your network at a microscopic level. In other words Wireshark is a network or protocol analyzer (also known as a network sniffer) available for free at the Wireshark website. It is used to analyze the structure of different network protocols and has the ability to demonstrate encapsulation.

Features of Wireshark :

1. Data is analyzed either from the wire over the network connection or from data files that have already captured data packets.
2. Supports live data reading and analysis for a wide range of networks (including Ethernet, IEEE 802.11, point-to-point Protocol (PPP) and loopback).
3. With the help of GUI or other versions, users can browse captured data networks.
4. For programmatically editing and converting the captured files to the editcap application, users can use command line switches.
5. Display filters are used to filter and organize the data display.
6. New protocols can be scrutinized by creating plug-ins.
7. Captured traffic can also trace Voice over Internet (VoIP) calls over the network.
8. When using Linux, it is also possible to capture raw USB traffic.

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Capturing network communication packets with Wireshark Utility

1. When you open Wireshark, the first thing you need to do is to choose the interface on which you need to capture the packets. ...
2. Once you click on start, then Wireshark starts to capture the packets on that interface.
3. You can stop the capture using the Capture->Stop or pressing Ctrl+e on the keyboard.

you can download Wireshark through there official website: https://www.wireshark.org/