Wireshark:
is a network packet analyzer. A network packet analyzer will try to capture network packets and tries to display that packet data as detailed as possible.Wireshark can capture traffic from many different network media types and despite its name including wireless LAN as well. Which media types are supported, depends on many things like the operating system you are using

Download Link : https://www.wireshark.org/download.html

Capsa:
is the name for a family of packet analyzer developed by Colasoft for network administrators to monitor, troubleshoot and analyze wired & wireless networks. Currently, there are three editions available: Capsa Enterprise Edition, Capsa Professional Edition, and Capsa Free .
Freeware Network Analyzer (Packet Sniffer) for students, teachers, computer geeks and other non-commercial purposes.

Download Link : http://www.colasoft.com/download/pro...capsa_free.php

NetworkMiner:
is a Network Forensic Analysis Tool (NFAT) for Windows (but also works in Linux / Mac OS X / FreeBSD). NetworkMiner can be used as a passive network sniffer/packet capturing tool in order to detect operating systems, sessions, hostnames, open ports etc. without putting any traffic on the network. NetworkMiner can also parse PCAP files for off-line analysis and to regenerate/reassemble transmitted files and certificates from PCAP files.
NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows that can detect the OS, hostname and open ports of network hosts through packet sniffing or by parsing a PCAP file. NetworkMiner can also extract transmitted files from network traffic.

Download Link : http://sourceforge.net/projects/netw...atest/download

SharpPcap:
is a cross-platform packet capture framework for the .NET environment, based on the famous pcap / WinPcap libraries. It provides an API for capturing, injecting, analyzing and building packets using any .NET language such as C# and VB.NET.

Download Link : http://sourceforge.net/projects/shar...atest/download

PacketSquare (CapEdit):
is a free and open-source pcap-based network protocol testing tool.[1] It is used for testing network devices (IDS/IPS, firewall, routers switches etc.,), networktroubleshooting, analysis, software and communications protocol development, and education.

A GUI PCAP Based Network Protocol Testing Tool.
Download link : https://code.google.com/p/packetsqua...downloads/list