(Wireshark (formerly known as Ethereal) is a network packet analysis software. The role of network packet analysis software is to capture network packets and display the most detailed network packet information possible. Wireshark uses WinPCAP as an interface to directly exchange data packets with the network card. In the past, network packet analysis software was very expensive, or was designed for profit. The emergence of Ethereal changed all that. Within the protection scope of the GNUGPL general license, users can obtain the software and its source code for free, and have the right to modify and customize the source code. Ethereal is one of the most extensive network packet analysis software in the world.)