Wireshark and its Function as Sniffer

In locations where complex systems and technology are used, in addition to the smooth flow of processes and steps, the aspect of system and network security is the focus of attention. When it concerns advancing industrial companies, own developments are often necessary, and their creation is usually documented on one or more computers. These sensitive data must be protected from hostile attacks, which resulted in establishing these so called sniffer programs that allow tracking and analyzing the data flow in order to find possible error sources and discrepancies. This is where the Wireshark comes in, which is a tool serving specifically for the analysis of network-internal communication connections. This software is publicly available.

The Sniffer Software

Wireshark is a program that works with the sniffer software and thus checks the data traffic within a network for implausible distinctive features and discrepancies. Consequently, this tool is used for network analysis and to a certain extent guarantees the smooth flow of processes in a computer system by detecting errors. A sniffer treats two different modes:

  • the non-promiscuous mode and
  • the promiscuous mode.

In the first mode, the incoming and outgoing data traffic is checked on your own computer. However, in the promiscuous mode, the entire data traffic that is transferred to the powered network interface is saved. As a result, also those frames are recorded that are not addressed directly. The advantages of using such a sniffer software and ultimately the profit by using Wireshark are

  • diagnosing network problems,
  • uncovering hacker attacks,
  • the network traffic analysis and
  • filtering data according to suspicious content.

The History of the Wireshark Creation

This program was created based on the "General Public License" initiative, and under the management of Gerald Combs. Initially, Gerald Combs was employed at Ethereal Software Inc., and the tool was originally also known as Ethereal. In 2007, the first version was put on the market, and it is known today under its more common name "Wireshark", as a free and open source software. Ethereal continues to be available on the market despite the fact that this predecessor is no longer being further developed. However, the basis on which both versions are working, are the network analysis products of commercial manufacturers. By now Version 1.8.5 is available, which can be used in the operating systems Unix, Linus, Solaris, Mac, and Windows. The program is not yet available in German.

Technical Details about Wireshark

While recording data traffic to a network interface, or after it is terminated, the collected data are made available as individual packets with this program. The purpose of the tool is to present the data clearly and to organize them so that a simple analysis is possible where people can logically trace the steps. With this structure in Wireshark, the collected recordings from the data traffic may be viewed and be broken down by content. Additionally, the many functions of the program allow preparing statistics about the data flow and extracting binary contents such as images.

The Mode of Action of Wireshark

The data, or here also data packets, are transferred via a network cable. The flow of data runs serial, so that the data are sent in bits strung together. The individual bits of the payload data are translated into corresponding voltage levels, so that these can be transferred to the corresponding cable. However, before the data reach the cable, each single layer of the seven layers of a protocol stack must be passed through. This happens in two simple steps:

  • Encapsulation - each layer adds a specific header to the data
  • Decapsulation - while passing through each layer, the header is removed again by the station for which the data are intended.

Wireshark Conclusion

Wireshark is a program that is used to capture data packets to allow a more precise analysis. The main focus of this tool is observing the data traffic within a network. Such a tool allows the user to examine his/her own computer for protocol errors and problems within the network architecture. Accordingly, Wireshark is also gaining significance within the information technology and network-internal communication, because by finding discrepancies, risks to the PC and its components can be prevented. From a security aspect it must be taken into account that such a program is helpful in discovering and stopping hacker attacks. Especially among people working in the industry, this can be of an advantage if sensitive data is stored on their computer that should never reach third parties.