Simple Packet Sniffer using Java

This document will help you make your very own small and simple packet sniffer using Java or in more explanatory terms, using the ‘waseda’ JPcap library.We will develop a simple command-line packet sniffer application on the Windows platform using the WinPcap packet capture library (you can alternatively use libpcapfor UNIX based machines).The document will flow in the given style:

Writing a Packet Sniffer
Definitions:
Packet Sniffing: is the process of capturing network traffic and inspecting it closely todetermine what is happening on the network. A sniffer analyzes the data packets of common protocols and displays the network traffic in human-readable format.
Libcap: a system-independent interface for user-level packet capture. Libpcap provides a set of functions independent from the hardware and the operating systemthat an application can use to capture packets from a network.
TcpDump: uses the functions exported by libpcap to capture packets, set packet filtersand communicate with the network adapter.
Winpcap: is an architecture that adds to the operating systems of the Win32 familythe ability to capture the data of a network using the network adapter of the machine(or in other terms, the libpcap for Windows).
WinDump: is the TcpDump for Windows from user point of view ( The kernel part isWindows specific and it is very different according to various Windows flavors).

JPcap: is a Java class package which enables to capture and send IP packets from Javaapplication. This package uses libpcap and Raw Socket API.P.S. Raw sockets and ICMP aren't available in Java natively, and this is where Jpcapcomes to the rescue!

Refer:

The winpcap is needed for the following opensource project. Or some exception would be issued when doing the development. eg. "no jnetpcap in java.library.path"

Winpcap: http://www.winpcap.org/docs/default.htm

Jcap:http://netresearch.ics.uci.edu/kfujii/jpcap/doc/index.html
http://pengtyao.iteye.com/blog/1603653
http://jnetpcap.com/