Wireshark.org - ( Open Source)
Wireshark helps network administrators to solve protocol issues by diagnosing the problems in the software protocols.
Wireshark is a famous network analysis or packet sniffer tool protocols.
Wireshark examine data from a live network, and can also take a snapshot of the various communications that work on it at another time. Wireshark proposes to see the "dissector tables" directly from the main window. The application can export objects to SMB screen or display the compiled BPF code for capture filters. Finally, Wireshark supports a variety of protocols such as ADwin, Apache Etch, JSON, reload or Wi-Fi P2P (Wi-Fi Direct).
The interface is quite austere, hides an extremely powerful that only experts can use software correctly.
This software is essential for any network administrator to diagnose problems in the software protocols.
Many user interface improvements have been made. See the New and Updated Features section below for more details.
Support for a number of legacy features and libraries has been removed. See the Removed Features and Support section below for more details.
The following bugs have been fixed:
Data following a TCP ZeroWindowProbe is marked as retransmission and not passed to subdissectors (Bug 15427)
Lua Error on startup: init.lua: dofile has been disabled due to running Wireshark as superuser (Bug 15489).
Text and Image columns were handled incorrectly for TDS 7.0 and 7.1. (Bug 3098)
Dumpcap might not quit if Wireshark or TShark crashes. (Bug 1419)